COT yy
Oates
SMITHSONIAN INSTITUTION
UNITED STATES NATIONAL MUSEUM
BULLETIN 224 PART 1 WASHINGTON, D.C.
1962
U.S. GOVERNMENT PRINTING OFFICE WASHINGTON : 1962
For sale by the Superintendent of Documents, U.S. Government Printing Office Washington 25, D.C. + Price $10.25 per set of Parts 1 and 2 (sold in sets only)
A FOSSIL ASILID SENOPROSOPIS (EOSENOPROSOPIS) ROMERI HULL, PRESERVED IN FLORISSANT SHALE. (PHOTOGRAPH COURTESY DR. FRANK M. CARPENTER.)
A RECENT ASILID PROTOCANTHUS PHILADELPHICUS MACQUAERT. (PHOTOGRAPH COURTESY DR. ALEXANDER B. KLOTS.)
Robber Flies of the World The Genera of the Family Asilidae
By FRANK M. HULL
Research Associate, Smithsonian Institution
Publications of the United States National Museum
The scientific publications of the United States National Museum include two series, Proceedings of the United States National Museum and United States National Museum Bulletin.
In these series are published original articles and monographs dealing with the collections and work of the Museum and setting forth newly acquired facts in the fields of Anthropology, Biology, History, Geology, and Technology. Copies of each publication are distributed to libraries and scientific organizations and to specialists and others interested in the different subjects.
The Proceedings, begun in 1878, are intended for the publication, in separate form, of shorter papers. These are gathered in volumes, octavo in size, with the publication date of each paper recorded in the table of contents of the volume.
In the Bulletin series, the first of which was issued in 1875, appear longer, separate publications consisting of monographs (occasionally in several parts) and volumes in which are collected works on related subjects. Bulletins are either octavo or quarto in size, depending on the needs of the presentation. Since 1902 papers relating to the botanical collections of the Museum have been published in the Bulletin series under the heading Contributions from the United States National Herbarium.
This work forms number 224 of the Bulletin series.
REMINGTON KELLOoGe, Director, United States National Museum
1V
Contents Part 1
Acknowiedements oss ck ae cue ey et ame nies kaa toe nis Pieeuoh vel a bdy OS Gas ss ix MGrOGUCHION sree cee-a oh hae tesa elise Senay ie da) NSN ome oe ves 8 ve Ps ta 3 AGI Benches css eis Son ty 5 ORC ee eae AE cL ne In ot ees gd cea teeth Se 25 DasypOCONIMACe Me Na swk OL ooo) Onan bop aera iy Ss toate esl eee) We eee bys : 26 Dio ctrin ity ee catego Re Re ReneS ee ah ene Aw Cee ig Min eis 26
hel liniiaeiecec tet veo in, ect a Baer ee ENG ch pease chee komme Mobacs a pet ola 43 CHrysOPOZONINI nee aye Gee er vn. RE, ae ayy ea ee ew Gee Sais 47
Dam alintirs cos pct eno Meena unteeee eis” eho er oS aoa), Seats sees 51 ap WY Stine he ek hee oes ae ey Ne i, “ap Enyeas ee we en etree eo Ges, al 72 SUCHOPOPONINIss ey Boek as. Une aniee eee Soca sect cee ay sO SCENOPOPOMINecmce tery Kins aon Gia) os) sonee ctedechae nce pete oe oe? eS 5 118 Dasypogzonini pes ce sy vie css fy ens Sara amas RE icn ce CeO aie Bao MBhereutrinigrage: tte Meare maar eles ce laey Remo aR aS oer Dh, VoLle fy oe gee Oi
NISMO MOLp MIN Wawa etee Swerve rere ckhs! «she seca et ahs Buc metros os neers ws 7 629i Weptocastrinaer., sos. cyrs ea fies erate. cla: a) ee german ioe tay Jotce Ab =e) 2296
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Part 2
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Text Figures Part 1
. Prosternum in asilids . . Mouth parts of asilids.
Wing of a generalized Recent eae
. Graduated dissections of Recent asilids .
. Graduated dissections of Recent asilids .
. Immature stages of Asilidae . j : . Concentration areas of asilid genera and pabeeneey ; . Distribution pattern of Dioctria Meigen .
. Distribution pattern of Damalis Fabricius .
. Head and wing, Bromleyus flavidorsus Hardy .
. Distribution pattern of Laphystia Loew .
. Distribution pattern of Microstylum Macquart .
. Distribution pattern of Plesiomma Macquart .
. Habitus, Dasypogon diadema Fabricius
. Distribution pattern of Diogmites Loew .
. Habitus, a species of Lagodias Loew : rites
; ies eanion pattern of Cophura Osten- Saree :
. Habitus, Leptogaster cylindrica De Géer .
. Wing and antenna of Leptogaster Geuneroniea en onde . Habitus, Ophionomima solocifemur Enderlein . ee . Habitus, Laphria gibbosus Linnaeus .
: Deebation pattern of Hyperechia Sehiner:
. Habitus, Hyperechia consimilis Wood .
; iibseeinertion pattern of Lamyra Loew .
. Habitus, Lamyra gulo Loew :
: Tsenbation pattern of Atomosia Weiecnart
. Habitus, Paratractia dasypus Wiedemann
3 Tistuibation pattern of Senobasis Macquart
. Habitus, Pseudorus piceus Walker
Part 2
Distribution pattern of Ommatius Wiedemann . Habitus, Blepharotes splendidissimus Wiedemann . Tccabatien pattern of Alcimus Loew . : Distribution pattern of Mallophora Mincansen Distribution pattern of Neraz Hull... . Provisional philogenetic arrangement of the ea
429
435 449 457 467 476 597
Acknowledgments
The ground work for this review was laid by a study of the collections at the United States National Mu- seum, the American Museum of Natural History, and the Museum of Comparative Zoology of Harvard Uni- versity. Especially important is the collection of the U.S. National Museum, containing as it does extensive material from North and South America and the Baker collection from the South Pacific, besides the recently acquired Bromley collection.
The extensive collections at the British Museum (Natural History), the Hermann collection in the Staatssammlichen Museum in Munich and the larger collections in Australia have also been studied, as well as material loaned by dipterists in the United States and abroad.
The National Science Foundation gave a grant which made possible the study of museum collections in the United States, England, Europe and Australia. The University of Mississippi provided a temporary Re- search Professorship, permitting travel time. I wish especially to thank the Honorable Walter Sillers of Rosedale, Mississippi, and the Honorable R. D, Morrow, Sr., of Brandon, Mississippi, for their willingness to encourage state support for this monograph.
I wish to express my deep appreciation to the Na- tional Science Foundation for support of this project. and for the helpfulness of the officials of that organization.
To the many persons who have assisted in this study, especially to officials of the Smithsonian Institution and its U.S. National Museum, I acknowledge with grati- tude my indebtedness. I wish to express my apprecia- tion to members of the Department of Agriculture staff at the National Museum, particularly to Dr. Willis Wirth for his deep interest in the project and to Mr. Curtis Sabrosky, who has been most helpful in advice and guidance concerning problems of nomenclature. For encouragement during preparation of the manu- script I shall always have a deep feeling of gratitude toward Dr. J. F. Gates Clarke, curator of insects at the National Museum. I should also like to thank the Mu- seum editor, Mr. John S. Lea who deserves especial mention for his patience and skill in getting the manu- script and drawings into print.
535914—62—pt. 1
2
Especially I express my appreciation to Dr. Frank Carpenter, Dr. P. J. Darlington and Dr. J. Bequaert of the Museum of Comparative Zoology; to Dr. Mont Cazier and Dr. Howard Curran at the American Mu- seum of Natural History; to Dr. Edward Ross, Cali- fornia Academy of Science; to Dr. P. D. Hurd, Jr., and Mr. A. T. McClay of the University of California; to Mr. Joseph Wilcox of the United States Bureau of Entomology, Whittier, California. I wish also to thank Dr. Charles H. Martin of Oregon State College, Mr. Henry Dietrich of Cornell University, Mr. George Steyskal of Grosse Ile, Michigan and Dr. George Byers of the University of Kansas. The late Dr. Stanley Bromley was generous in his assistance.
I owe a debt of gratitude to the authorities of the British Museum (Natural History), Mr. N. Riley, Dr. W. E. China, and Mr. H. Oldroyd, and their staff; to the late Dr. Fritz van Emden of the Commonwealth Institute; to Dr. George Varley and Mr. B. M. Hobby of the Hope Museum, Oxford University; to Dr. Rich- ard Frey of the University Museum, Helsingfors; to Dr. Willi Hennig of Deutsches Entomologisches Institut; to the late Prof. Hassan C. Efflatoun Bey; to Dr. A. J. Nicholson and Dr. D. F. Waterhouse of the Australian Commonwealth Scientific and Industrial Research Or- ganization of Australia and those of his efficient staff named below; to Dr. W. Forster and Dr. F. Kiihlhorn of the Staatssammlichen Museum in Munich; to Prof. J. Timon-David, University of Marseilles; to Sr. Messias Carrera of Sao Paulo; Mr. B. R. Stuckenberg, Natal Museum, Union of South Africa.
There were many in Australia who were generous in their help, and to them I extend thanks: Mr. R. T. M. Pescott and Mr. Alexander Burns of the National Mu- seum; to Dr. and Mrs. (Dr.) I. M. Mackerras of the Queensland Institute of Medical Research; to Prof. F, A. Perkins and Dr. Elizabeth N. Marks of the Uni- versity of Queensland; to Mr. George Mack of the Queensland Museum; to Mr. A. Musgrave of the Australian Museum; to Dr. P. D, F. Murray, Dr. A. R. Woodhill, and Mr. J. R. Henry of the University of Sydney; to Mr. D. J. Lee, Public Health and Tropical Medicine, University of Sydney; to Mr. H. Womersley, South Australian Musuem; to Mr. Harry Lower of
ix
x ACKNOWLEDGMENTS
Waite Agricultural Research Institute, Adelaide; to Mr. G. H. Hardy of Katoomba, New South Wales; to Mr. Athol Douglas of the Perth Museum; to Mr. E. F. H. Jenkins, Government Entomologist, Perth; and to Dr. A. J. Nicholson’s staff of the Commonwealth Scientific and Industrial Research Organization: Dr. S. J. Paramonov, Mr, Edgar Riek, Mr. K. R. Norris, Mr. Tom Campbell, Dr. M. J. D. White, Mr. Frank Gay, Mr. Paul Wilkerson, Mr. M. M. H. Wallace, Mr. John Callaby, Mr. Keith Taylor, and Mr. Don Wilson.
The fine and valuable drawings prepared by Mr. Arthur Smith deserve special mention. His services were available through the British Museum (Natural History), and he is responsible for a large part of the illustrative material. His beautiful work has added much to the project. The remainder of the drawings were done by the author.
I wish to thank Dr. Frank M. Carpenter and Dr. Alexander B. Klots for furnishing the two photographs in the frontispiece.
I should like to thank the many librarians, who have used their special talents to help locate obscure references.
Finally I wish to express my deep appreciation to my wife, Mary Marguerite Chappell Hull, who has spent countless hours in typing manuscript and checking list of species; her painstaking work has lightened and shortened the task,
Frank M. Hou Department of Biology University of Mississippi University, Mississippi January 15, 1961
Robber Flies of the World: The Genera of the Family Asilidae Part 1
Introduction
HE ROBBER FLIES, OR ASILIDAE, comprise one of the
largest and most abundant families of present day insects. Distributed through all parts of the world, over 400 genera and subgenera have been proposed and about 4,761 species are known. In addition, 18 genera and 39 species have been described from the Eocene, Oligocene, and Miocene; 15 of these genera are also Recent. Because of their predatory habit of feeding on other insects and their voracious appetites, they con- tribute to the maintenance of the natural balance among insect populations. To some extent, parasitic wasps and flies are taken by them, but much of their prey consists of plant-feeding insects. Certain species are known to seriously deplete the populations of apiaries. The adults are, with few exceptions, active flies, of con- siderable size and readily attract attention.
Hermann Loew in 1847 began a world study of the Asilidae; his publications on this project continued until 1874. During the last half of the nineteenth century, many dipterists contributed to our knowledge of this family. Today, much excellent work is being done regionally on the Asilidae. The present study integrates all previous work, in order that a basis for a world concept of the group may be laid.
It is hoped that this study will afford persons in widely separated parts of the world means of identi- fication of their own fauna and a Imowledge and appreciation of the fauna of other regions. Considera- tion has been given to the evolutionary trends and distribution of the genera, tribes, and subfamilies.
History of Studies
Linnaeus (Linné; 1758), in his tenth edition of “Systema naturae” erected the genus A silus, ascribing to it 11 species, and added 4 others in his twelfth edition (1767) of the same work. Of these 15 species included in the genus by Linné, 10 have been assigned to other genera, 2 remain in Asélus and 3 cannot be recognized with certainty, because of the brevity of the original descriptions. A list of reassignments of Linné’s species is given under the subfamily Asilinae. His species Asilus crabroniformis (1758), stands as the type of the genus Asélus and the type of the family Asilidae. Fam- ily status is credited to Leach in Samouelle (1819).
J. C. Fabricius, in five publications from 1775 to 1805, describes 76 exotic and European species and erected the genus Damalis. Wiedemann, from 1817 to 1880, de- scribed 235 species, many of which were exotic. He proposed 3 genera, all of them used today. Meigen, 1800 to 1838, described many species in his treatment of the European asilids and in an early work of 1803 erected 4 genera, 3 of which now represent subfamilies.
About the middle of the nineteenth century, a number of dipterists made significant contributions to the study of the family Asilidae; among them were Loew, Macquart, Walker, Rondani and Bigot, but none more important than the indefatigable Loew, who, besides describing great numbers of species, proposed 83 genera, 75 of which are still recognized, although 5 of these names required changing on account of preoccupation. Later, considerable work was done by Schiner, Willis- ton, Lynch Arribilzaga, Philippi, Jaennicke, Roeder, and Becker. By 1900 a total of 254 genera had been proposed, of which 170 are still valid. During the first half of the twentieth century, many careful students of the Asilidae have appeared. Very excellent contribu- tions have resulted from the studies of Hermann on the South American genera, Engel in his monumental vol- ume on asilids in Lindner’s “Die Fliegen der palaeark- tischen region” and Efflatoun’s “A monograph of Egyptian Diptera. Family Asilidae,” besides the work of Oldroyd, Becker, Bezzi, and Ricardo. White made pioneer studies of Australian asilids and was later followed by G. H. Hardy.
In North America, Hine became early interested in this family. Shortly thereafter Curran, Bromley, Pritchard, Wilcox, James, and Martin industriously contributed many papers; and recently Carrera has made important contributions to a study of the South American fauna. A recital of past studies of Asilidae reads very much like a directory of dipterists, so popu- lar has been this family and I have for reasons of space omitted many well known dipterists who made briefer contributions. The student is referred to the bibliog- raphy for the work of others to whom credit is also due.
The bibliography covers a span of 200 years and con- tains the work of about 387 authors and 1344 titles.
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4 UNITED STATES NATIONAL MUSEUM BULLETIN 224 PART 1
Comprehensive bibliographies in all fields of entomol- ogy are scarce and much to be desired. In Diptera the fine bibliographies of Bequaert (1953) on Hippobos- cidae, and of Henning (1952) are superior to any I have ever worked with. Crampton (1942) gives 356 references in a bibliography of Diptera morphology. In this work the bibliography of the Asilidae ends with the year 1954, except that references I have been able to obtain for the years 1955-1960 are included.
The species list, which has been included with the genera and subgenera, is offered as a practical and im- mediate aid for the encouragement of students, new and old alike. In the preparation of these species lists I have followed Kertész (1909) in his world catalog of Diptera, except that for Europe I have adopted al- most entirely the disposition of Palaearctic species as given by Engel (1925-30). For the United States most asilid species are well known, except those of the genus Asilus Linné, which require additional study. The scope of this study of genera has not permitted a review of the more than 4,700 species in order to substantiate their generic location. Where I have been privileged to see specimens of species, I have used the information acquired to assign them to a proper place according to the concepts of this study; other- wise not. The Asilidae of Europe and North America above Mexico are rather well known, but many of the species of older authors, especially Macquart and Wiedemann and others remain but poorly known and require new study in the light of present day generic concepts. This is especially true of Ast/us Linné Dasypogon Meigen, and Laphria Meigen. The check- list of the species of Asilidae ends with 1954, except those of Wilcox and Martin, and Hull through 1958.
T have adopted much but not all the synonymy indi- cated or suggested by Ricardo in her valuable series of papers; I have done so particularly in those cases where she has had access to the Walker and Bigot types. Ricardo also made several trips to see the Macquart types. And for the same reason I have accepted the synonymy given by G. H. Hardy where he has stated that he has seen the types. Perhaps this is an appropriate place to call attention to the state- ment of Collin (1933), who in his study of the Diptera of Patagonia and South Chile notes that Z’mpis cotow- anthus Blanchard is certainly not an empidid. Collin suggests that it may belong to the family Asilidae; it should prove most interesting to students of this family.
This work attempts to furnish the minimum ade- quate illustrations for each genus. Past publications on the family Asilidae have provided, in rather scat- tered places, more than 3,781 figures of asilids or parts thereof. This figure represents a tally for only those papers that give an exact count and have been used by me; I am sure that the number would be greater if all scattered and occasional illustrations were included. Many of these illustrations are excellent, but some are
too small to be effective and useful. I wish to call especial attention to the 305 figures of Melin (1923) ; the 384 figures in Seguy (1927); the 210 figures in Carrera (1949) ; the 284 figures of Engel in Lindner; besides the 352 text figures and 82 superb, colored, whole figures of the late H. C. Efflatoun (1937).
Every student of taxonomy builds on the work of others. I wish to pay especial tribute to the fine work of the late Dr. Stanley Bromley in the United States and to Dr. Friedrich Hermann in Germany. Her- mann proposed 48 genera. Attention must also be called to the signal contribution of Melin (1923), whose monumental and painstaking work on the mor- phology of immature stages and the behavior of asilids is our best study on this aspect of these Diptera.
Relationships and Phylogeny
The study of ancestral relationships of the several families included among the Brachycera is filled with difficulty. As Cazier (1941) and others have pointed out, in any study of phylogeny it is essential that the most fundamental characters, those least likely to be affected by adaptive specializations, be utilized for understanding relationships. The author takes the view that when the relative value of the wings, the legs, the mouthparts, the antennae and the terminalia are considered, the wings and terminalia are least likely to be affected by adaptive changes. The terminalia, of course, do show some adaptive changes centering around both mating and egg deposition. Provided a wing has sufficient number of veins to support its re- sistance to air, it is not likely to change, except as a progression. The wing is, then, in many instances, likely to be a true indication of relationships. How- ever, parallelisms arise also in wing venation. Com- parison of fossil asilids shows how little change has taken place in wing venation. It is interesting that those families with the most constant activity and of larger size have the most veins in supporting the wing membrane. For example, Mydaidae may be quite large, and they undoubtedly are decadent, but they are agile and excellent fliers. The bombyliids and the asilids put even greater demands on their respective wings and their veins are stout, numerous and the wing rather well subdivided.
In searching for indications of common relationship, the dipterist cannot fail to be impressed by the general similarity of the wing of the rhagionid, the therevid, the tabanid and such lower members of the asilids as have all marginal, posterior, and anal cells open. The asilids, apioceratids, therevids, and mydaids appear to form a natural group. In this work, the Asilidae are considered to have a position off to themselves, but more closely related to the apioceratids than to the mydaids. The asilids are set apart by the presence of the simple, bristlelike empodium. In most of the other families of Brachycera, the pretarsus is characterized
INTRODUCTION
by a distinct, padlike, pulvilliform structure or aro- lium; rarely is a medial appendage of some kind want- ing. Asilids seem to be an early and ancient offshoot from the common stock which gave rise to present day representatives of above mentioned families and which, at a still earlier time, diverged in another direction to produce the families of the Bombyliformia (Bombyli- idae, Cyrtidae, Nemestrinidae).
One of the greatest gaps between the Nematocera and the Brachycera lies in the character of the palpus. Palpi of Nematocera are composed of three to five segments; palpi of Brachycera are composed of one or two segments. We have no Brachycera with three palpal segments. Following Williston, 1908, palpi are considered of great significance, and have been ex- amined in each asilid genus. In the lower Dasypo- goninae, in a few generalized types, there is a trace of the antepenultimate segment of the palpus. Williston, 1908, gives a summary of past systems of relationships.
Loew recognized three principal subfamilies of the Asilidae, the Dasypogoninae (Leptogaster Meigen in- cluded), the Laphriinae, and the Asilinae. Schiner (1868) proposed the subfamily Leptogastrinae. Loew emphasized the distinctions of the antennae and wings, and to some extent those of the head, legs, thoracic chaetotaxy, and terminalia. Williston (1908) con- sidered the palpal differences to have more fundamental significance than the state of the marginal cell. Mal- loch (1928) and others pointed out the great diversity of antennal forms within each subfamily. Hermann (1920) made a useful subdivision of the Dasypogoninae into three major groups. His divisions, the Prytani- nae, Eremocneminae, and Acanthocneminae, are based on the reduction in the number of visible abdominal segments, and on the presence or absence of the fore- tibial apical spine. Engel (1928) preserved this ar- rangement. Hermann’s distinctions, while certainly significant, have the disadvantage of a poor choice of names, since none of them stem from names of genera. For this reason, and because additional tribes have been recognized, Hermann’s subdivisions have not been used in this work.
Among recent schemes of classification, Carrera (1949) followed Hardy (1934) in recognizing only 2 subfamilies and placing the Laphriinae with the Dasypogoninae and the Leptogastrinae with the Asi- linae. Bromley, Hermann, Engel, Williston, Me- lander, and Verrall have recognized 4 subfamilies and I believe on good basis. For a basis of recognizing Dasypogoninae, Asilinae and Leptogastrinae, we have fossil records; each of these groups goes back as far as the Miocene. The Asilinae extends into the Oligo- cene and Eocene. No fossil species of Laphriinae are yet known. It may be a relatively Recent subfamily. In the Laphriinae we find 77 genera and about 763 species, which occur in all the major world regions. The features shared in common by the Laphystini and the Laphriinae suggest that this subfamily arose from the ancient stock of that tribe.
ROBBER FLIES OF THE WORLD 5
Hardy (1948) placed dependence on the relative dis- sociation of the prosternum as a defining character for the higher categories. In some Asilidae the proster- num represents a single or paired, or paired and more or less fused sclerite which is completely isolated by membrane from the lateral propleuron. In others it is solidly fused with the lateral propleuron completely around the anterolateral border of the anterior coxa; this condition is described as a complete or undissoci- ated prosternum. Clements (1951) has shown that there is great instability in the character of the pros- ternum within many groups of asilids. This character seems to have then, in brief, the same defect that the antenna has, in being too variable in this family. Be- cause of the interest attached to it, I have given the condition of the prosternum considerable attention, and have examined its state in a wide variety of lower Brachycera and some Nematocera in an effort to de- cide which condition is the more generalized, the com- plete or the dissociated prosternum. Such a great variety of genera scattered throughout the order have the prosternum dissociated that one might be inclined, because of this very fact, to regard the isolated pro- sternum as the more primitive state for Diptera; but there are certain evidences which suggest that the re- verse is true and which confirm Hardy’s conclusion that the complete prosternum is the generalized con- dition. With a dissociated sternum surrounded by membrane, there is made possible a greater flexibility, but less strength because of reduced muscle attach- ment sclerites. Both conditions appear to be desider- ata in a highly predatory group and it seems likely that adaptive factors have entered prominently into the state of the prosternum in various genera of the lower Brachycera. This may account for the lack of a trend in many groups toward the exclusion of the one type or the other.
Thus, I find that the following genera in other fam- ilies have the prosternum fully dissociated: Rhagio Fabricius, Dialysis Walker, Atheriv Meigen, Chrys- opilus Macquart, Symphoromyia Frauenfeld, and Co- enomyia Latreille. But in Solva Walker, on the contrary, the prosternum is complete, well developed, and fused. The prosternum is also dissociated in Culex Linné, Tipula Linné, Leoprosopa Macquart, Eclimus Loew, Syrphus Fabricius, Milesia Latreille, Cochliomyia Townsend, and likewise in all muscoids and higher Diptera which I have examined.
On the other hand the tabanids, stratiomyids, doli- chopodids, therevids, and empidids, at least generally, have the prosternum fully developed and complete, al- though the first three families named above evidence in common a peculiarity which suggests a relationship and perhaps origin from common stock; this is the curiously broadened state of the prosternum, leaving the anterior coxae far apart. Of the therevids, there is a close resemblance between their prosternum and that of members of the Stichopogonini, where it is also
6 UNITED STATES NATIONAL MUSEUM BULLETIN 224 PART 1
fully fused and complete laterally. Moreover, there- vids have a bristle-type empodium, which, together with venational similarities, suggests that they may not be far from the asilid line of ancestry.
As far as the general sequence of events with regard prosterna, I draw the following conclusions: 1, The complete prosternum is generalized and ancestral in asilids and probably in all Brachycera; 2, the need for strength of muscle attachment in asilids coping with vigorous, struggling prey has perhaps retarded the definite trend towards a breakdown of the pro- sternum; and 3, the prosternum is in process of being broken down in most if not all groups of asilids today, because of the premium on flexibility of the anterior subraptorial legs. This conclusion is strengthened by the fact that within the same genus the larger the asilid, of those asilids which have a reduced pro- sternum, the greater, proportionately, is the amount of membrane surrounding the prosternum. I further point to the condition in Coenomyia Latreille, illus- trated in text-figure 1, which shows the prosternum at a point of just complete separation from the lateral propleuron.
As regards the conclusions to be drawn from the state of the prosternum with reference to the phylo- geny of groups within the asilids themselves, one must proceed with caution, because of the widespread tend- ency within a family for suprageneric groups to proceed along parallel lines. The prosternum is most variable, at the present time, in the Asilinae, as observed by Clements (1951), but here again it appears to be com- plete in the more primitive elements, except that it is not clearly possible usually to point to definitely prim- itive genera. For instance, Veraz, new genus, might be regarded as specialized with respect to behavior of the veins at the apex of the wing, yet the arrangement of the anterior branch of the third vein, and the fre- quent vestiges of former connecting veins, complete in some related forms, represent a primitive trait. In de- termining the relationships of genera and groups of genera, the total picture of their development as it emerges from a study of the whole insect must be taken into consideration and I fully agree with Clements that the prosternum cannot be used, except in indicating the affinities of a genus. I have used it only once in this study to differentiate between genera, for instance, to separate the African Leptogastrinae genus Ammophilo- mima Enderlein, from the Asiatic Lagynogaster Her- mann, and then only in connection with other char- acters. Broadly speaking, the character of the pro- sternum does help to define the tribes Laphystini and Atomosini because it is universally complete in these groups, or at most shows but slight emargination in the former tribe.
In this work the family Asilidae is subdivided into five subfamilies: Dasypogoninae, Megapodininae, La- phriinae, and Leptogastrinae, which we hold to consist of one interrelated group, and lastly, the Asilinae, which is considered to be somewhat more distantly related to
the other four. In point of size in terms of species (the species count as given is approximate), the bulk of all Recent robber flies fall into the Dasypogoninae and Asilinae.
The Dasypogoninae contain about 1,887 species, whereas the Asilinae contain about 1,852 species. In the Megapodinae are 33 species, a few of which older names may be synonyms. The Leptogastrinae contain about 252 species, to which 24 others have been added by Martin, 1957. In the Laphriinae there are about 763 species.
The Dasypogoninae are here divided into the fol- lowing tribal associations: Dioctrini with about 112 species, Phellini with 7 species, Chrysopogonini with 18 species, Damalini with 119 species, Stichopogonini with 141 species, Thereutrini with 7 species, Enig- momorphini with 1 species, Laphystini with 93 spe- cies, Stenopogonini with about 829 species, and the Dasypogonini with about 510 species.
The Laphriinae are divided into the tribes of Laphriini with 446 species, the Andrenosomini with 117 species, the Atomosini with 185 species, and the Ctenotini with 15 species.
I call further attention to the proportions within the Laphystini, where the genus Laphystia Loew has 42 percent of the species in this tribe. In the Damalini we find Damalis Fabricius in the Old World with 43 species and Holcocephala Jaennicke in the New World with 40 species. Collectively they total 69 percent of the tribe or about the same proportion as Leptogaster Meigen in its subfamily; divided they each total 33 percent and 35.8 percent of the totals within the tribe.
The Megapodinae in this work have been treated as a subfamily.
It is of interest to note that the large genus Laphria Meigen contains about 254 species or about 33 percent of the subfamily Laphriinae; and that in the tribe Atomosini, the large genus Atomosia Macquart contains 58 species or about 33 percent. Again, the tribe Andre- nosomini contains the large genus Andrenosoma Ron- dani, which is about 37 percent of the species.
However, we find that in the subfamily Leptogas- trinae with about 276 species there is a single, large genus Leptogaster Meigen with about 210 species or almost 76 percent of the total. It is not, however, sur- prising to find some genera of flies unusually large, as for example Anopheles Meigen, Tabanus Linné, Li-
monia Meigen, and it does not necessarily follow that -
they should be broken up into numerous genera and subgenera. Sometimes the recognition of well marked and distinct species groups serves just as useful a pur- pose and may more accurately reflect the true state of affairs.
The Asilinae are divided into the tribe Ommatini with approximately 187 species and the tribe Asilini with about 1,665 species.
In this work the Dasypogoninae, with their open, marginal cell and 2-segmented palpus, are regarded as the most generalized members of the family. Two other
INTRODUCTION ROBBER FLIES structures appear in some but not all members of this subfamily and are of considerable phylogenetic significance.
The first of these structures is the modification of the female ninth tergite into a pair of lateral, adjacent plates, the acanthophorites, together with their accom- panying hemicircle of spines; this results in a character- istic type of ovipositor, which is restricted to the higher tribes of this subfamily only. Strictly analogous struc- tures have appeared two or more times in the Asilinae,
Text-Ficure 1.—The prosternum in asilids and in Coenomyia Latreille; stippled areas indicate membrane: a, Coenomyia ferruginea Scopoli. B, Om- c, Andrenosoma xantho- p, Nerax concin-
matius sp. cnema Wiedemann. natus Williston.
as in Proctacanthus Macquart, Philodicus Loew, but located on the tenth segment. Certainly the spiny out- growths on the ninth tergite of the Phellini and also in some species of Chrysopogonini, both tribes of the lower Dasypogoninae, seem to be analogous rather than homologous, although there is a definite splitting of this tergite in Psilozona Ricardo into distinct acan- thophorites.
These spines on the acanthophorites are a character of special interest. There are similar structures on most if not all female Therevidae, on many Mydaidae, and on female Apioceratidae. Malloch (1928) has noted such structures present in some species of the an- thomyid Hylemya Desvoidy and in the bombyliid genus Comptosia Macquart and the Anthracinae. Such structures in these families may be analogous to those
OF THE WORLD ts
of asilids. Lf so they are differently constructed and of independent origin. If these structures are not anal- ogous, then these several families are closely related.
However, while these spines, when present in ther- evids and mydaids, certainly do seem remarkably similar to those of the Dasypogonini, I do not believe them to be homologous. For so clearly are they absent in some divisions of all three of these families that it does not seem that such groups represent a loss of such structures.
Also these spines and acanthophorites are lacking in the lower Dasypogoninae, the Laphriinae, the Mega- podinae, the Leptogastrinae, and all the Asilinae, and in consequence I can not regard them as generalized structures. Rather they have the appearance of being adaptive specializations for the purpose of egg deposi- tion and have appeared more than once in the Diptera. I do not believe that they have arisen more than once in the Dasypogoninae, except as crudely analogous types in the lower groups as above cited. Melin (1923) comments on the insertion of the egg in sand by the asilid Zasiopogon Loew and Cyrtopogon Loew. In common with several persons, I have followed the steps in oviposition in this family. In western Arkan- sas I have watched the asilid Diogmites Loew drill the egg hole in hard soil, insert the abdomen, deposit the
8 UNITED STATES NATIONAL MUSEUM BULLETIN 224 PART 1
egg and tamp the whole with the end of the abdomen and the outstretched spines. Melin (1923) says that Philonicus Loew in the Asilinae uses the spines as a sort of brush.
It will be noted that the larger the fly the larger and stouter the spines become; thus in small and weak flies like Brachyrrhopala Macquart and Stichopogon Loew they are slender and delicate. I attach no great significance to the supplementary setae that are present in some of these smaller genera, and in some therevids. They are found only in the smaller, weaker flies and are found laterally and ventrally to the spines. Per- haps they represent the type of bristle that has become modified into these so-called ovipositoral spines.
In summary, these five tribes of the Dasypogo- ninae—the Dioctrini, Phellini, Chrysopogonini, Dama- lini, and Laphystini—seem never to have acquired these ovipositoral spines, except rarely and always in an analogous form, and are here regarded as general- ized Asilidae. Together these tribes comprise 28 per- cent of the Dasypogoninae genera.
The second important acquisition in the subfamily Dasypogoninae is the anterior tibial apical spine. This structure is not a true morphological spine, but is a stout, thickened or swollen bristle, which has become spinelike; it is appropriate to refer to it as a spine to avoid comparison with stout setae or bristles often present on these flies. However, in some genera it may be accompanied by or borne on a spinelike process or outgrowth from the apex of the tibia.
In at least the larger forms and possibly in all asi- lids which show it, this spine appears to be an adaptive mechanism, possibly useful as a small, raptorial clamp in holding struggling prey until the proboscis and its quieting juice can be inserted. These spines may have developed at a time when the salivary juices of the fly were less potent in their paralyzing and stupefying effect. This spine may be polyphyletic in origin. There are several distinct types as well as de- grees of development. Once emerged, it is not un- common to find three coincident types of adjacent and associated structures. The first is the extension of the base of the spine into a strong protuberance, reaching a maximum in Molobratia Hull (Dasypogon of au- thors). The second is the coincident appearance of opposing denticles on the base of the anterior basi- tarsus. These are frequently found but may be quite absent. The third type is the swelling of the basitar- sus, with or without denticles, into a conspicuous flange or mound, reaching a peak in WVeolaparus Williston, Megapoda Macquart, and allies.
Because the foretibial spine itself is of several types, as well as in several stages of development, it has been criticized as a distinguishing character. The follow- ing major types of such spines are recognizable: First, the slender, twisted or sigmoid spine as is found in Cophura Osten Sacken and its allies; it has little and sometimes no corresponding basitarsal develop-
ment. The second type is the stout, well developed spine with at least a moundlike, denticulate, basitarsal swelling. The third type is a stout, straight spine at- tached to a strong protuberance which extends beyond the tibial apex with correspondingly exaggerated basi- tarsal process as above cited. These second and third types may represent continued specialization from the same stock as Cophura Osten Sacken, the cophuroid genera possibly having arisen from ancestral forms, which have been retarded; or at least arisen from those which have retained a generalized form of the spine. Another view is that these several types of spines in the Dasypogonini represent separate polyphyletic or analogous developments of the foretibial spine.
Thus far I have had reference to the several types of anterior tibial spine only as seen within the tribe Dasypogonini. I have relegated Codula Macquart to the Chrysopogonini on account of its notopleural spine. Members of this genus lack completely any trace of the tibial spine, from which I conclude that the other genera in the tribe acquired the tibial spine independently. Again, Leptarthrus Stephens, with a small, bent, tibial spine and no trace of ovipositoral spines has been assigned to the Dioctrini. Here again it is believed that these two exceptions may possibly represent parallel acquisitions of the tibial spine. If this is true we may consider that the tibial spine has arisen three or more times in the Dasypogoninae, and once in the Megapodinae.
In this study the Dasypogoninae are divided into ten tribes. The Dioctrini, with all cells of the wing generally open and with a trace of the antepenulti- mate palpal segment, is placed lowest, and followed by the Phellini, the Chrysopogonini, the Damalini, and the Laphystini. The Stichopogonini are considered nearest the Dasypogonini. The spined and not spined genera of the higher Dasypogoninae have been sepa- rated into the Dasypogonini and the Stenopogonini.
I reject the tribal name Saropogonini used by some authors and based on the spined, front tibia, because the name should be Dasypogonini. Some but rather less than half of the unspined Stenopogonini can be separated in the male sex by the not rotate terminalia.
In any case, the presence or absence of the spine is extremely useful in classification. Megapoda Mac- quart and its allies have been raised in this study from tribal status to subfamily rank. I am inclined to re- gard the Laphystini as the highest of the not spined Dasypogoninae, because of their reduction in the seg- ments of the abdomen, but it is possible that the Dama- lini are more specialized. They are also a very suc- cessful group, and, together with the Stichopogonini, they dominate such habitats as sandy shores and mud flats. In the higher Dasypogoninae, some 75 genera lack foretibial spines, while approximately 50 genera have acquired them.
The principal line of cleavage in the Laphriinae has to do with the chitinization of a medially fused and complete postmetacoxal arch. It separates the Atomo-
INTRODUCTION
sini from the Laphriini and also the Andrenosomini with the exception, that in some species of Proagonistes Loew there is a media] seam on the arch. The Andre- nosomini, with eleven genera, are regarded as an off- shoot from the Laphriini, as are likewise the Ctenotini.
Except for the Ommatini, the Asilinae have not been subdivided. The Asilinae segregate compara- tively well into those genera in which the anterior branch of the third vein lies above the wing apex and those where it falls below. The first group is filled with such diverse types as Promachus Loew, Procta- canthus Macquart, and Polysarca Schiner. The second group is even more variable, so I have decided to leave them all in one group. The Asilinae, if they include the more ancient known fossils, are also the most suc- cessful present day forms, dominating as they do fields and grasslands. Powerful, active and aggressive, these larger forms are matched in ferocity only by the spe- cies of Microstylum Macquart in the Dasypogoninae. The larger asilids do not hesitate to defend themselves when captured by the collector and the unwary will be quickly and viciously bitten by them,
The palpus has been reduced from two segments to one in at least five groups—the Asilinae, Leptogas- trinae, the Megapodinae, in Enigmomorpheus Her- mann, and in the Ctenotini. The marginal cell has become closed five times in this family—in the Asilinae, some Laphystini, all Laphriinae, most Megapodinae, and in all Thereutrini.
It seems apparent that the Asilidae are better de- veloped today, both in point of genera and species than in the early or middle Tertiary. Compared with the family Syrphidae, we find that today the Asilidae has about the same number of species, though a great many more genera and curiously more subgenera. But there are almost certainly many more species of asilids undescribed than there are of syrphids. Known fos- sil species of Asilidae total 39, whereas the syrphid fossil species number 75, and of this number, 30 are from the Baltic amber, against only 4 asilids from Baltic amber. However, the habits of asilids are per- haps not such that amber would make a likely trap for these flies. If the amber fossil syrphids are subtracted from the number of known fossils in this group, there still remain 45 syrphids from rock or shale formations compared with 35 asilids from similar formations.
In each of the larger subfamilies of the Asilidae there appears to be at least one or more actively differentiat- ing or evolving groups. For the Dasypogoninae this would seem to be the Laphystini, the genus Cophura Osten Sacken with its related genera and the genus Microstylum Macquart with its related genera. For the Laphriinae, the presently best developed group would be the Atomosini; for the Asilinae, the Vera, new genus, group of species and genera and perhaps Promachus Loew.
Several trends in the family appear to have resulted in well marked phylogeronts. One of these is giant- ism, which appears several times in the family, in
ROBBER FLIES OF THE WORLD 9
Phellus Walker and in some species of Microstylum Macquart. Clumsiness, as well as giantism, is appar- ent in some species of Bombomima Enderlein, and they have become about as robust laterally as they can well be, and some of these lay very large eggs, with consequent reduction in number, though admittedly the hazards for initially large larva may be less, as far as our present knowledge goes. If, as some believe, these larva are predatory, this too may well be a lim- iting factor in these species. I believe we must regard Phellus Walker species, Obelophorus Schiner, Dasy- lechia Williston as phylogeronts; perhaps too, all or most of the Megapodinae are such. Dwarfism appears in the Stichopogonini, as well as in some minute and fragile species of the Leptogastrinae and Atomosini. There are some parallel developments as in species of both Acronyches Hermann and Systellogaster Her- mann, which resemble flies of other families. One species of Acronyches Hermann has the milky wing apex seen among the Syrphidae, in similarly petiolate species of Microdontinae and Cerioidinae, and in wasps. Most remarkable is the genus L’urhabdus Al- drich with the threadlike abdomen, long-stalked hal- teres and wing reduced in the basal half to a mere stalk.
Morphology
The robber flies are characteristically large, active, aggressive flies, which tend to have bristly vestiture, a short thorax and a stout, yet tapered abdomen. The abdomen, in contrast to therevids, tabanids, nemestri- nids and bombyliids, is always reduced in girth at the point of attachment to the thorax. This latter condition is probably connected with the hovering habit present in all four of these other families, and possibly in several of them is associated with air sacs. Asilids are able to hover but do so uncommonly, The robber flies are very efficient predators. They either pounce on their prey or capture it in flight with great agility. Surely the unusual development of the legs, so often stout and swollen and beset with strong bris- tles, is connected with this predatory habit. The eyes are prominent and well developed, without exception widely dichoptic in both sexes, and the front of, equal width in both. In a few Leptogastrinae the eyes may virtually meet beneath the antenna. This is the gen- eral picture of the family, but with so many genera and species there are numerous exceptions. Some asi- lids are weak flies with few bristles and delicate in body.
The head in most asilids is of medium length. In a few instances, especially in some Damalini, it is shortened, the eye being high, short, and flattened. The postocular occiput or that part which shows be- hind the eye profile is generally prominent and some- times especially well developed. Occasionally the upper occiput is obliterated by the posterior develop- ment of the eye, but the great uniform expansion of the eye with concave, posterior occiput, such as in tabanids, some bombyliids, and nemestrinids is never
10 UNITED STATES NATIONAL MUSEUM BULLETIN 224 ; PART 1
found. While it is usually stated that the vertex is strongly and characteristically excavated, there are a few exceptions: In Ancylorrhynchus Latreille it may be quite plane; in Damalini the enlarged and flattened eyes are greatly raised above the vertex and in this group and in some Laphriinae, such as Cerotainia Schiner and Rhopalogaster Macquart, the upper oc- ciput and vertex are posteriorly flared and excavated.
The face of Asilidae is well filled and is in contrast to the sunken, excavated face of rhagionids and there- vids. It is without the deep and conspicuous lateral
Text-FicurE 2.—The mouth parts of asilids, as illustrated by Nerax interruptus Macquart. Expianation: 1, theepistoma. 2, maxillary palpus. 3, the labrum. 4, the maxillae. 5, the hypophar- ynx. 6, the labium.
punctures and creases of the mydaids and some taba- nids. The vertical, lateral face grooves in the Asilidae are best developed in the Damalini and in Plesiomma Macquart. There is frequently a well developed tu- berele or gibbosity over the whole or lower part of the face and a marked tendency toward stout, long, conspicuous bristles above the epistoma. These bris- tles are often called the mystax. The antenna is gen- really placed a little above the middle of the head, and in Dioctrini and Zrythropogon White it is placed high above the middle of the head, thus shortening the front. Three antennal segments are present and in the majority of genera there is at least one terminal microsegment, small or large, and sometimes there are two well developed microsegments, in addition to a terminal spine, or bristle, which may be likened to an- nuli. The end segment often has such a spine:or bris-
tle present apically or subapically. In the Asilidae and some others the third segment bears a long, stout bristlelike terminal style or arista.
Both front and ocellarium usually bear bristles and their position and number are of some value in classifi- cation. A single ocellar pair may become prominent to the exclusion of others, or there may be only stiff pile present.’ The subepistomal area is the clypeus; it is usually distinct from the face. Characteristically, the proboscis is straight and usually longer than the head, that is, it extends beyond the anterior boundry of the face, but may be reduced, minute, and short in the tribe Atomosini. In Aneylorrhynchus Latreille its shape is very peculiar, blunt, short, stout, and directed down- ward and backward. In others the direction of the pro- boscis is often characteristic, being held horizontally forward and the presence of a high, dorsal keel is noted in some genera. Again, the apex may be cylindrical, bifid, depressed dorsoventrally or laterally compressed. Hansen (1883) and Melin (1923) give the anatomy of the mouth in detail. The proboscis consists of a stout, usually cylindroid labium, which forms a tube or cyl- inder that is open and slitlike dorsomedially and holds within it the paired, thin-blade, curved maxilla and the unpaired tubular, bristle-beset hypopharynx, the in- terior of which forms the food canal. Piercing of the prey is done with the hypopharynx and enters the prey at the sharp apex. Above these structures, situated dorsally and chiefly toward the base lies the epipharynx (labrum-epipharynx). This is the structure, which constitutes the middorsal keel of the proboscis. The mandibles are quite rudimentary or absent.
The maxillary palpus lies at the base beside the labium. Itis of great significance in the classification of these flies, and in the higher asilids it is reduced to a single segment. In some of the lower forms, there are traces of a third segment. It is interesting to note that in all except the more generalized species the basal seg- ment is hemicylindroid, that is, it forms a hollow hemi- cylinder, or shell, and various stages of partial fusion of this segment to the lower gena are noticeable. Again, the terminal segment in certain groups is perforate at the apex, the opening may be quite large. In Brachyrrhopala Macquart and allies this end segment is swollen and clavate, with one flattened surface, and re- sembles the rhagionid palpus.
The thorax is stout and the sclerites strong and thick. Generally, stout macrochaetae are present and are often conspicuous, long, and numerous. They are most useful in classification. The pronotum may be short, without anterior ridge, or if such ridge is present, there is a fur- rowlike depression between and the anterior ridge bears the macrochaetae. Prosternum in the lower forms generally dissociated from the lateral propleuron, but fused in many asilids. The mesonotum is gently curved before and behind, usually more abruptly anteriorly and in some cases is as greatly raised and humpbacied as in some empidids. Metathorax small and reduced, but elements lie above as well as below. The ventral
a
INTRODUCTION
ROBBER FLIES OF THE WORLD 11
Text-Ficure 3.—The wing of a generalized Recent asilid, Cera- turgus cruciatus Say. ExpiLaNaTiIon: Costa. 2, Subcosta or auxiliary vein. 3, First branch of the radius, or first longi- tudinal vein (Ry). 4, Second longitudinal vein (Rg and Rs). 5, Third longitudinal vein (Ry and Rs). 6, Anterior branch of third vein (R;). 7, Posterior branch of third vein (Rs). 8, First branch of medius or fourth vein (M;). 9, Second branch of fourth vein or anterior intercalary vein (M2). 10, Third branch of fourth vein, or posterior intercalary vein (Ms). 11, First branch of cubitus, or fifth vein (Cu). 12, Second branch of fifth vein (Cuz). 13, Second anal vein. 14, Main stem of the radius (R). 15, Main stem of the medius (M). 16, Main stem of the cubitus (Cu). 17, First anal vein. 18, Remnant
metasternum may be wholly membranous, thinly chitin- ized, or more rarely forming a stout, thick arch of chitin.
The legs are almost always stout, often swollen and frequently bear numerous, stout bristles. These condi- tions are connected with the active, predatory habits and the need to hold a struggling prey. As Lundbeck (1908) has so well commented, the bristles are of several different categories. They may be stout throughout, or stout basally, becoming fairly attenuate distally; or in many cases, they are so weak as to render it difficult to decide if they are truly bristles or only bristly, stiff- ened hairs. Al] tibiae at their apices have several, stout, spinelike bristles. The cluster may contain as many as 10 or 12 on the hind tibial apex or as few as 5 or 6 bristles. The anterior tibial apex may have a single bristle, which in the course of evolution has thickened into a prominent spine. Its accompanying modifica- tions have been discussed above. The pretarsus ends in pulvilli, sometimes reduced or even absent, and a bristle- like empodium of several forms and variable length, wanting in only one or two Leptogastrinae genera. Claws may be sharp, or blunt, curved or flattened and apically bent; in not pulvillate forms, they become more slender, always finely attenuate and convergent;
19, Anterior branch of cubitus. 20, Ambient vein. 21, Radial sector. 22, Humeral crossvein. 23, Anterior, small or middle crossvein. 24, Posterior or medial crossvein (m). 25, Discal or mediocubital crossvein. 26, First
of third anal vein.
or basal costal cell. 27, Costal cell. 28, Subcostal or medi- astinal cell. 29, Marginal cell (Ry). 30, First submarginal cell (Rp and R3). 31, First posterior cell. 32, Discal cell (Ist M;). 33, Second submarginal cell. 34, Second posterior cell. 35, Third posterior cell. 36, Fourth posterior cell. 37, Fifth posterior cell. 38, First basal cell. 39, Second basal cell. 40, Third basal, anal or lower basal cell. 41, Axillary cell, anal angle (A,). 42, Alula, axillary or posterior lobe. 43, Thy- ridium. 44, Arculus.
rarely the lateral claw is shortened.
With few exceptions, the wings have a complete am- bient vein, rarely entirely absent (Vusa Walker). The radius is 4-branched always, with sometimes a recur- rent spur extending back from the anterior branch of the third vein near the base of this branch. This spur vein is sometimes complete; that is, it unites with the second vein and in Mallophora Macquart and several other genera it simulates a crossvein. It is really equivalent to the posterior branch of the second vein (third branch of radius), which has become lost, and a spur vein, when present, constitutes a vestige of this last vein. The medius has 3 branches, the cubitus has 2 branches and the anal cell open or closed and petio- late. In the most generalized condition, the marginal and all posterior and anal cells are open. This condi- tion is seen only in the lower Dasypogoninae and the Leptogastrinae. In many forms, the marginal cell is closed; one and sometimes two posterior cells and the anal cell may be closed or a total of four closed alto- gether. In one instance the submarginal cell is closed. Rarely, the posterior cells may be reduced to four cells; in one instance it is reduced to three cells; the alula is absent in Leptogastrinae and in a few other genera likewise.
2, UNITED STATES NATIONAL
MUSEUM BULLETIN 224 PART 1
The asilid abdomen typically has eight well developed tergites in the males and females, those beyond being incorporated within the terminalia or the ovipositor. In the female Asilinae, if the proctiger be counted, ten segments can be discovered, but in other subfamilies sometimes fewer. In one tribe and subfamily the pre- abdomen is reduced to six visible segments. Macro- chaetae, with few exceptions, are present on the sides of the first tergite. They are more rarely present on remaining tergites, still more uncommonly on sternites. In a few asilids the abdomen departs from the usual stout and tapered, cylindroid form to become wide and greatly flattened (Blepharotes Westwood) or wide and stout and robust (Hyperechia Schiner, Laphria Mei- gen). Rarely are asilids petiolate. A few have long, very slender bodies, as in the sluggish Leptogastrinae. The first sternite may be subdivided into two or more bands of thin chitin.
In the Asilidae the male terminalia are complex and, as is true of so many Diptera, quite variable. Since there is still much confusion of terms in dealing with these structures, I shall define below the terms I have adopted in this work. I have consulted both Crampton (1942) and Cole (1927), but I have relied chiefly on the terminology employed by Emden and Hennig (1956).
The genitalia of the asilids and Diptera in general
Text-Ficure 4.—a-s, Bombomima fulvithorax Fabricius: a, deep dissection with right clasper and pseudoclasper removed; B, with gonopod removed. c, Nerax interruptus Macquart, with superior forceps and gonopod removed. pv, Neoaratus sp., with superior forceps removed, revealing paralobus and clasper.
comprise the ninth abdominal segment with marked modifications in consequence of its function. The ter- gal component is referred to as the epandrium, except where it is furcate, in which case it is here styled the superior forceps; this structure bears the proctiger at its apex medially, a structure called by some authors the lamellae and called by others the cerci, with due recognition, perhaps, to the eleventh segment origin of the true cerci. The proctiger, as found in the Asilidae, may possibly represent parts of both tenth and elev- enth segment (telson) elements; partly paired as it often is by reason of a dorsal, lineal fissure, it repre- sents a small, tubular passageway.
On the ninth segment, the ventral or sternal element or hypandrium, is usually present and is often extraor- dinarily prominent; however, it is greatly reduced in some genera and may be virtually or completely lack- ing, as in Clephydroneura Becker; on the other hand it is extended dorsally in Bathypogon Loew and even fused to the epandrial element, from which the supe-
INTRODUCTION
EXPLANATION,
Text-Ficures 4 anp 5 1, Eighth tergite. 2, Eighth sternite. 3, Epandrium. 4, Hypandrium. 5, Gonopod. 6, Superior forceps. 7, Aedeagus. 8, Penis guides (or sheath). 9, Proctiger. 10, Clasper. 11, Pseudoclasper. 12, Paralobus. 13, Hamate process. 14, Cavity of superior forceps. 15, Cut edge of superior forceps. 16, Cut edge of gonopod. 17, Aedeagus sheath. 18, Cavity of gonopod. 19, Penis sheath.
Text-Ficure 5.—a-c, £, Diogmites platypterus Loew: A, exterior view of gonopod with processes; B, medial view of gonopod with processes; c, aedeagus and sheath from ventral aspect; E, lateral aspect with true right gonopod and whole proctiger removed. D, Astochia sp., the superior forceps removed.
rior forceps do not begin until some distance from the base of the segment.
Between the superior forceps (epandrium) and the ninth sternite, there is usually a well developed, paired, lateral organ somewhat shorter than the epandrium and attached to or borne by the ninth sternite. This is the inferior forceps of Oldroyd (1938), and to avoid the additional use of the word forceps, I have uni- formly called this structure the gonopod, since it is borne dorsally from the hypandrium. This lateral structure appears to be equivalent to the gonopods of authors. Beyond this point the confusion with regard to the characteristic, distal processes so often seen in the Asilidae grows greater, and since clear evidence of seomental character is wanting, I have rejected the use of the terms styli or surstyli for these processes. It will be noted that the lateral gonopod often bears a medial, more or less upright, arched and sublamellate process tending to enclose the aedeagus (distiphallus) ; I have followed Oldroyd (1938) and others in calling
ROBBER FLIES OF THE WORLD 13
this lateral and medial appendage the clasper, when it is clearly borne by the gonopod. This structure, the gonopod, when present tends to enclose the penis guides when these are present, which in turn encloses the aedeagus. However, the clasper is sometimes either lacking or greatly reduced. Again, the clasper may be double, with four structures in two pairs (two on each side) of nearly equal prominence and each arising, as in Astochia Becker, from the medial base of the gonopod. The outermost of these structures are here called pseudoclaspers. There may be a similar structure arising rarely from the inner wall of the supe- rior forceps as in Oligoschema Becker, sensu stricto, and I call this the paralobus. The accompanying text- figures 4 and 5 show graduated dissections in lateral aspect of a representative of each subfamily. Attention should be called to the rotation or inver- sion of the male terminalia. A considerable literature has arisen on the controversial subject of the mechanics and mode of inversion. Those interested in the sub- ject are referred to Lamb (1922a). Rotation usually takes place during copulation in the Dasypogoninae, but the terminalia are permanently rotate 180 degrees in the subfamily Laphriinae. In Asilinae and Lepto- gastrinae they are not rotate at all and the superior forceps and accompanying proctiger are always dorsal in position. Since in Dasypogoninae the rotation oc-
14 UNITED STATES NATIONAL MUSEUM BULLETIN 224
curs while in copulation, these parts tend to return to a variable extent to the dorsal position and in the dried cabinet specimens they are usually found in partial and sometimes complete inversion. Probably, in many Dasypogoninae there is permanent rotation, if judgment can be formed from dried material. In the Dasypogoninae, except the Stenopogon Loew group of genera, this male character cannot be used with com- plete confidence because of its variability, nor can it be linked as an associated character with the female char- acter of the spiny acanthophorites in the tribe Dasy- pogonini. Some of the members of the tribe Dasy- pogonini are not rotate, such as Stenopogon Loew and Bathypogon Loew.
In the lower Dasypogoninae the female terminalia are simple and begin with the ninth segment. If there are fewer segments in the preabdomen than eight, the apparently missing segments can still be found, short- ened, and concealed or partially hidden beneath the last visible segment. In the Dasypogonini and Sticho- pogonini, the ninth female tergite is subdivided into two lateral plates, the acanthophorites, leaving on each side a quarter-circlet of stout spines which are sharp, blunt or spoon-shaped, and usually consisting of five or more pairs. In the lower Dasypogoninae, as Phel- lus Walker and Dioctria Meigen, and in all the Asilinae this tergite is undivided.
Immature Stages
The eggs of asilids vary both in size and shape. They range from very short oval as in Leptogaster Meigen, and Bombomima Enderlein, to medium oval in the case of Laphria Meigen, in which the length of the egg may be twice the width. Melin (1923) figures 14 asilid eggs and states that the eggs of Laphria are reddish brown and shiny. The egg he shows of Futol- mus rufibarbis is nearly four times as long as wide. Eggs of one large species of Bombomima Enderlein are very large, purple in color and short oval.
Larvae of Asilidae are elongate, tapered at each apex. They tend to be shiny, sometimes furrowed, or with fine stria and with or without dorsal] callosities. They possess a clear, distinct head with eleven body seg- ments, which often have rows of minute pores. The terminal segment is divided. The principal spiracles consist of a pair on the prothorax and a pair on the anterior abdominal segment, for which reason they have been regarded in all older writings as amphipneu- stic. Green (1918) found a pair of minute, possibly not functional spiracles on the metathorax, and a pair on the remaining, abdominal segments. The penulti- mate abdominal segment is shorter than the ultimate, distinguishing them from the mydaids, but like them the body is held straight; hairs of ultimate segment not closely approximated as in mydaids. In text-figure 6 several typical larvae are shown, after Melin (1923), to whom the interested student is referred for his fine, detailed studies and figures.
Asilid pupae are of the free and mobile type. Antennal sheaths are ‘present, sometimes divergent,
PART 1
situated close to the medial part of eyes. Melin (1923) designates the distinct, thornlike processes, which are found at the base on the one hand, and the distal part of the sheath on the other, as the anterior and posterior processes. Posterior processes generally have three to five teeth. Melin (1923) and Green (1918) both con- sider that the abdomen consists of 8 segments. Dor- sally the segments are provided with a unilinear girdle of spines, which Melin finds change over laterally into bristles, and which Brues and Melander (1932) find alternate as long and short spines. Eight spiracles are generally present.
More than fifty authors have dealt with the egg, larva, or pupa of Asilidae. As Melin (1923) has pointed out, most of the descriptive and illustrative material, excepting that produced by Malloch (1917) and by Greene (1918), is without comparative value as it goes into entirely too little detail. Many of the observations made on the supposed feeding habits of larvae is of a presumptive or circumstantial character. Melin in his own work states that he had almost a thousand larvae representing many species and not a few genera. Altogether about 50 species have been treated in literature, distributed approximately as fol- lows: Dasypogoninae with 5 genera and 13 species; Asilinae with 17 genera, and 27 species; Laphriinae with 5 genera and 9 species; Leptogastrinae with 2 genera and 4 species. Seguy (1932) illustrated a num- ber of larvae and pupae, many from Melin (1923). The bibliographies of Melin (1923), Irwin-Smith (1923), and Henning (1952), should be consulted by those interested in these stages.
Ecological Relationships
The majority of species of Asilidae frequent dry and sandy areas, a condition well shown by the greater numbers of species found in arid and semiarid regions; but even in desert or semidesert country the small drains of dry steam beds attract the greatest number, and sometimes the entire robber fly population of a region will be restricted to such places, which also have the maximum vegetation and the greatest population of insects upon which the flies feed. In such country one may often look in vain for Asilidae beyond the banks of the stream bed. In temperate regions a few species occur in wet swamp areas and deep forests. As Bromley (1946) has pointed out, the number of species which occur deep within woods is limited, and these flies tend definitely to concentrate on the edges of woodlands, where shrubs occur and give way to grassland. I spent several weeks at the Canal Zone Biological Area of the Smithsonian Institution, on Barro Colorado Island in Gatun Lake. There in the rain forest never was an Asilid seen within the forest, but several species occurred among the high grass along the edge of clearings. There are species which prefer grasslands, and the plains also have their repre- sentatives. Next to semidesert areas, probably savan- nah country attracts the greatest number. It is said
INTRODUCTION
Sr. ee apical Circular = Callosity
\.- prothoracte PS 3 cle
ae) Contractile r —" processes
lateral Callosity
---dorsal Callosity
nti ge Aaterion 15 op
Scnon me.
= ra segment (Chee = Spiracle ia} Nae : termina? Ji bristles
A b B
that about 500 or more species occur in California; this may be attributed to the very diverse habitats and cli- mates, of the State and to its length.
Robber flies begin to move several hours after sun up and are occasionally active until sunset. Gener- ally speaking, they are most active from 10 in the morn- ing until 2 in the afternoon and are strongly affected by hot, bright sunshine. A few species have short lives of but a week or ten days; aggregates of other species may live for six months. In the southern United States Nerax interruptus Macquart, a ubiquitous species, appears early in June and lasts until Novem- ber or later, depending on the appearance and severity of frosts. This species is called by the southern ne- groes, who are country-living, by the peculiar folk name “louanners.”
It is surprising how limited the population may be in some species of Asilidae. A population of 50 or more individuals of a species in an area of limited extent may be found, and it may be a very consider- able, even remote distance to other populations. I re-
ROBBER FLIES OF THE WORLD 15
_Prothoracic ” Splracle
antennal processes
poste coc spiracle
» dorsal Contractile YF callosity Ce SS y)
oF legs
wing
_.. lateral Sheate NN
Comractile
process Tag
~vewtral
Contractile Abele migss” process
Spiracle. coer bateral Callosity. —.-. Spiracle \ter minal processes
terminal plate with SER» spine like process
D
Text-Ficure 6.—The immature stages of Asilidae (after Melin, 1923): a, Larva of Machimus atricapillus Fallen. B, Larva of Dysmachus picipes Meigen (as forcipula Zeller). c, Larva of Choerades gilva Linné. pb, Pupa of Machimus atricapillus Fallen.
call finding a population of Asilus rubicundus Brom- ley in a hilltop plot of field grass beside a highway. There were scattered patches of woods and fields total- ing hundreds of acres, but these flies were centered in a small area of not more than one-half acre and in a 3-day period I netted 152 individuals. It was esti- mated that 20 more remained. A search the same days in a number of similar areas, including those where formerly the species was located, failed to re- veal others. Two days of collecting once yielded over 100 individuals of the very large Proctacanthus mil- berti Wiedemann from two acres bordering a swamp, and other individuals remained. Similar isolation of populations was noted by me in Australia. On the other hand, there are species and genera and tribes which are particularly abundant and can be found at most any time and place within the geographic range and proper habitat. Many asilids frequent the bark of trees or logs, drift wood, mud flats or the twig tips of small trees and shrubs. Some are restricted to pine forests, a not surprising fact in view of the extensive,
16 UNITED STATES NATIONAL MUSEUM BULLETIN 224.
evergreen forest of the northern hemisphere. James (1938) gives a good discussion of asilid habitat prefer- ences for the State of Colorado.
It is well known that these flies have certain resting or observation sites and greatly preferred ones. I re- cently made use of such a post to capture a series of Atomosia puella Wiedemann. The site was the black trunk of a wild-cherry tree some 50 yards from a house, and with other trees nearby. Over a 2-week period I found from three to six flies on that part of the tree trunk directly in the sunlight and extending from a foot above ground to some seven or eight feet above. <As fast as the immediate population was captured, others within the space of a few hours would move in from an unknown source; 54 flies were caught there. These flies were not present on nearby trees or outbuildings. Melin (1923) records an instance of what he considered the ability of a robber fly to modify an instinctive behavior pattern to suit circumstances.
We do not know the limiting factors in population size in asilids. Lack of available insect prey, as far as the adult insects are concerned, is perhaps infrequently, maybe never, a factor. It is possible that the larvae, about which we know little, may find food scarcity a limiting factor. A rather strong contributing factor may be inept behavior or low ability of the individuals in some genera to capture prey. Melin (1923) and Efflatoun (1937) both comment interestingly on the numerous, unsuccessful attempts of genera such as Epitriptus Loew and Cerdistus Loew, to capture prey.
Melin (1923) describes the mating habits of a num- ber of species in this family. He found that prenup- tial behavior is rather limited and this coincides with my own observations. I once watched Promachus bastardi Macquart hover behind a female selectively for a brief period before mating. The most highly developed courtship reported in the family is the spe- cies Heteropogon lautus Loew, as described by Brom- ley (1933), and of species of Cyrtopogon Loew, as reported by Wilcox (1936). In the species of Hetero- pogon Loew the front tarsus is decorated, and many of the American species of Cyrtopogon Loew, in contrast to European species, have elaborate, tarsal ornaments. Waving of the ornamented tarsi, accompanied by wing movement and at times a low buzzing sound are the chief movements, says Wilcox (1936d), who adds that the process may be accompanied by the male lashing the abdomen or striking the head and thorax of the female with the forelegs. When mated, pairs often fly without uncopulating, in which case the female usually takes the lead in flight, the male with vibrating wings, but facing the opposite way. The hum of mated couples in flight is of a distinctly lower pitch.
Most robber flies emit a characteristic hum, some- times of low, sometimes of high pitch, according to the size and character of the species. Many species are exceptionally wary; of none is this more true than the giant Australian species of Phellus Walker, which are difficult to catch.
PART 1
The recorded enemies of asilids consist of spiders, ac- cording to Bromley (1914), and wasps are recorded as enemies of asilids by both Bromley and by Melin (1923). Csiki has recorded one instance of birds feeding on a robber fly. Quantitatively, one of the principal enemies must be asilids themselves. Possibly lizards may feed on robber flies. Mantids capture an occasional asilid.
PREY
Asilid prey has been given considerable study by Hobby, Poulton, Bromley, Carrera and many others. Out of the numerous publications on food selection by these flies, a few patterns emerge. Certain species in Europe and North America eat hive bees and do great damage at times to apiaries. They have been blamed for the failure of hives of bees in New York state to throw offa swarm. The bee killer of that state is Promachus fitchii Osten Sacken. In Texas the cor- responding species are Saropogon dispar Coquillett and Diogmites symmachus Loew and in southern Europe Dasypogon diadema Fabricius is widely known as a bee catcher. According to Bromley (1934) Parkes records the killing of over 700 Saropogon dispar Co- quillett in one bee yard in a 3-day period. Besides these named, many other species have been captured and found with occasional bees. Very few if any in- sects completely escape the attraction of the predatory robber flies. In England even dragon flies have been listed among their prey. Some species are compara- tively unselective.
Melin (1923) states that Dioctria Meigen species catch mainly Hymenoptera. Hobby (1932b) found that Dioctria rufipes De Geer captured 40 percent Hy- menoptera with a predilection for Ichneumonidae; 55 percent of the remaining prey consisted of Diptera. Linsley (1944) noted that of 22 prey records of Callini- cus Loew, all were Osmia and Andrena bees. Hobby (1931a) in a lengthy and commendable study of asilid prey and behavior analyzes the prey captures of 23 British species. He notes that the capture darts of species like Laphria Meigen may range up to 6 meters and that Leptogastrinae characteristically hunt on the wing rather than by sudden sallies from an observa- tion post. I have frequently found Leptogaster Mei- gen species dangling by a foreleg while sucking their captured prey. ‘The time required to consume the prey varies with its size, but Edwards (1883) watched a robber fly of the group Asilinae capture eight geomet- rid moths in 20 minutes. Melin (1923) hazards some estimates of feeding time.
Mated asilids are not infrequently seen with the fe- male holding prey of some kind. I have not infre- quently found J/egaphorus Bigot mating with a female and in turn holding prey. I have found Proma- chus bastardi Macquart feeding on Megaphorus clausi- cella Macquart. Several other instances of asilids feeding on asilids have been recorded, even those of the same species. I have seen cannibalism in Megaphorus Macquart. Poulton (1906), records cannibalism in
INTRODUCTION
Dasypogon diadema Fabricius as an apparent accom- paniment to courtship. Several dipterists have been in- terested in the relative ease with which robber flies sub- due their prey and accounts are summarized by Melin (1923). Several students have commented on the ra- pidity of the paralysis of the victim after capture, and Bromley (1923) describes the striking ability of Proctacanthus rufus Williston to reduce a live bee to the status of a mere shell, by extracting nearly all of the digestive, nervous, and muscular systems. It appears to be unknown whether this reduction is aided by a his- tolytic enzyme, but in view of the results accomplished, it appears likely. While insects with extremely hard ex- terior covering like Curculio and Hister are captured by asilids, there is a relationship between the strength of the mouthparts and the capacity of the fly to subdue very hard insects. It has been reported that an asilid attacked unsuccessfully a chrysidid wasp, which, though held for some time by the fly, was eventually loosed and flew away unhurt.
LARVAL HABITS
The larvae of many genera live in soil. The larvae of the Laphriini and Andrenosomini usually live in decaying wood in old stumps, or beneath bark. I have seen no record of the larval habits of the Atomosini. The larvae of the asilids have been frequently re- garded as predatory in habit, especially by early writ- ers. Perris (1871) found Laphria gilva Linné asso- ciated with Spondylis buprestoides and Criocephalus rusticus, both beetle larvae, and considered that they were preying on these beetles. Riley (1870a) found Nerax femoratus Macquart larvae preying more than once on grasshopper eggs.
Malloch (1917) states that all the larvae of the fam- ily that he has found are predatory, feeding on other insect larvae in soil as white grubs or in decaying wood. Melin discusses the evidence up to the time of 1923 with considerable detail. His own observations and experiments are quite to the contrary and he be- lieves that the principal food of asilid Jarvae is vege- table in character. He presents what seems excellent evidence that asilid larvae subsist on a non-carnivor- ous-type of food. Melin believes that attack or con- sumption of animal food sources such as insect larvae is entirely secondary and sporadic, if indeed it ever actually takes place. While Malloch (1917) and Greene (1918) state that asilid larvae feed on other in- sect larvae, they do not claim to have verified this by direct, personal observation, that is, to have seen asilid larvae initiate the attack and extract the contents from larvae prey. The females of the large group of genera in the Dasypogonini are equipped with circlets of spines on the acanthophorites of the ovipositor and many members of the Asilinae likewise have such ac- cessory structures but of a different pattern; both groups deposit eggs in the soil.
ROBBER FLIES OF THE WORLD 17
Melin (1928) records the rather unusual egg-laying habit of Dysmachus picipes Meigen, which deposits eggs regularly in the spikelets of an ear of Avena or Dactylus, and this author gives figures of known asilid egg shapes. Apparently, the young larvae, upon hatching, fall to the earth, the fall being retarded by the bristly hairs. Again, he noted Neoitamus cyanu- rus Loew ovipositing in alder buds and strobiles. I once captured a very large species of Bombomina En- derlein, which immediately laid two quite large, pur- plish, very short, oblong eggs. Hardy (1929) records the ovipositing of the curious Werterhaptomenus morus Hardy. He found that the female repeatedly inserted the slender, thin, apical segments of the ab- domen down small holes made by beetles on the twigs of Acacia trees and that the fly moved from hole to hole feeling with its ovipositor until such a place was located. A captive specimen in the laboratory readily oviposited within the holes of a cork. Kershaw (1912) has shown that at least one Oriental species of Pro- machus Loew deposits its eggs within an ooetheca-like case on grass stems.
MIMICRY
As regards mimicry in this family, it seems less well marked than is found in the Syrphid flies or butterflies. Melin (1923) does not accept the existence of mimicry in the Asilidae, but in this I believe that he is mistaken. Species exhibiting mimicry increase in hot, humid lati- tudes and may be quite lacking in the temperate lands. Shelford (1902) calls attention to a species of Laphria Meigen resembling the Hymenopteron Salius serioco- soma; and also Hyperechia fera Wulp resembling the bee Xylocopa latipes. An African species of Hyper- echia Schiner was noted by Marshall (1902) to closely resemble the bee Xylocopa flavorufa. The Amazonian species of Dasyllis Loew, which resembles bees of the group Hulaema and the various species of Diogmites Loew and Llepharepium Rondani, which resemble some species of wasps, may be considered examples of mimic- ry. The small asilid Megaphorus clausicella Mac- quart from the southern United States is a good mimic of Megachile bees. These examples are generally re- garded as falling in the principle of synaposematic mimicry, or mimicry of aggressive resemblances. Both Shelford (1902) and Poulton (1925) have made con- tributions on this subject. Aggressive mimicry favors aggression and offers a measure of protection from cer- tain enemies. Some species produce a loud buzzing sound in flight not unlike some bumblebees. The curi- ous Chilean asilid Lycomya germainii Bigot has for its model the Hymenopteron Llaphroptera scoliaeformis Haliday.
The American series of mimics from the southwestern states copy the tarantula hunting wasps of the genus Pepsis Fabricius. These noteworthy insects are large, with black or blue-black bodies and wings strikingly colored a yellowish brown. Besides the robber fly Asi/us midas Brauer, the series contains Mydas xanthopterus
18 UNITED STATES NATIONAL MUSEUM BULLETIN 224
Loew, two large staphylinid beetles, and a large, con- spicuous ichneumonid-type wasp. Insouthern Arizona Blepharepium secabilis Walker occurs in company with a similarly colored sphecid wasp upon which it preys; the wasp isa little larger than the fly.
Cryptic coloration exists in some forms. Desert spe- cies especially tend to match the sandy background and many Laphriini and species of the Atomosini and species of Andrenosoma Rondani match the bark on which they rest.
Death feigning has been observed in some captured asilids and has been remarked by Teale. I have noted that Proctacanthus milbertii Macquart may remain in catalepsy from several seconds to several minutes. How often this state is reached or occurs under natural conditions is not known.
Zoogeographic Relationships
The Asilidae are world wide in distribution. The majority of the species and genera are found north of the southern tropic, the reduced land masses below this latitude producing fewer. Certain groups signifi- cantly characterize certain regions. No endemic or introduced species are known from the Hawaiian Is- lands but Laphriini and some other types occur sparsely on the smaller island groups. All larger is- lands south of Asia have a rather abundant asilid fauna, and a few extend onto Fiji, Samoa, New Zea- land, and one species is found on Christmas Island.
It is possible to point to genera which constitute characteristic features of certain regions. In the Neo- tropical region the Megapodinae are unique. In the same region we find a concentration of the Atomosini and the Holcocephala Jaennicke branch of the Dama- lini, as well as the prominent, southward extension of Diogmites Loew of the Dasypogoninae and of Neraa, new genus, from the Asilinae. Probably Mexico and northern South America can be regarded as the home of the last two named genera; however, the United States is very rich in representatives of both.
In the northern hemisphere the genera Laphria Meigen, Cyrtopogon Loew, Lasiopogon Loew, and the genus Astlus Linné, sensu lato, predominate. The Neolophonotus Engel group of the Asilinae and the genus Microstylum Macquart of the Dasypogoninae are especially well represented in South Africa. In south- ern Asia and the larger South Pacific islands, the beau- tiful, metallic flies of the genus Afaira Schiner replace Laphria Meigen. Oddly, the Laphriinae have pro- duced the metallic species in the genus Lampria Mac- quart in the New World tropics, which seem to parallel Maira Schiner.
Certain rather numerous, small areas or pockets of concentration in terms of genera and subgenera appear as a result of mapping the more than 4700 species of Asilidae to the point given for the type species. I refer to these regional spots as regions of concentration. I have attempted to show approximately these regions of concentration as small, shaded areas on the map in
PART 1
text-figure 7. The numbers on these dark areas refer to how many genera or subgenera are associated with each area, and which may be regarded as endemic for these areas. Many of the small, shaded areas cor- respond to the floristic regions of the world as illus- trated by Good in Map 4 of his work “The Geography of the Flowering Plants,” published in 1947. The wider, unshaded areas on the map indicate the addi- tional genera which have a wider distribution. No implications of origin are made for the genera of these areas, although, doubtless, most of these genera had their beginnings there. The generic totals given in the tables below for these small areas do not include other genera which occur in the same region, but which also have a widespread, or more or less continent-wide, or world-wide distribution.
There are 10 asilid genera of nearly world-wide distribution: These genera are Laphystia Loew, Stichopogon Loew and Suropogon Loew of the sub- family Dasypogoninae; Leptogaster Meigen of the Leptogastrinae; Laphria Meigen, Andrenosoma Ron- dani and Pogonosoma Rondani of the Laphriinae; and Ommatius Wiedemann, Promachus Loew, and Neo- ttamus Osten Sacken of the Asilinae. Of these genera Saropogon and Laphria are excluded from South America and Zaphystia is excluded from Australia.
As examples of such areas of concentration, the Chilean region has 16 characteristic genera; the Ama- zonian area has 7 such genera; what is here termed the La Plata region, including the eastern part of South America south from Rio de Janeiro as far as Buenos Aires, has 33; and other areas are shown on the map. In North America, curiously, there appear to be 18 characteristic genera, of these 13 genera characterize the south-central part of the United States west of the Mississippi River and only 3 characterize the States east of this river. South Africa shows 88 character- istic genera, of which 14 might be called genera found in the Cape region. There are, in addition, 9 other genera peculiar to central Africa. The Mediterranean area has 20 genera and the Transcaucasus has 15 genera, both of these areas being exceptionally interest- ing in terms of their special asilid fauna.
Especially interesting are the population values in terms of genera and species for small regions and specific localities. Lists for specific localities are very scarce or wanting. For Oxford, Mississippi, in a 8-mile radius I have found 49 species in 28 years of collecting. My list of Asilidae from Mississippi is still quite incomplete, but will probably compare well with the Florida list of 96 species by Bromley (1950). Bromley (1934) listed 161 species from Texas, a list which is also incomplete and reflects at once the large size of that State and the increasing aridity. James (1938) listed 122 species from Colorado. Johnson (1925) listed 45 species from Maine, 72 from Massachu- setts, and Bromley (1946) listed 68 Asilidae from Con- necticut. Bromley (1950) listed 94 species from Ohio, and in 1932, listed 28 species from Patagonia and South Chile. Verrall (1909) listed 23 species from England,
INTRODUCTION ’ ROBBER FLIES OF THE WORLD
Vee AR AIA
"i ears us 7H
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Pe le ee
a ae rp ig
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it
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Text-Ficure 7.—Concentration areas of asilid genera and subgenera.
11 from Scotland and 1 from Ireland. Seguy (1927) WESTERN HEMISPHERE—CONTINUED lists 133 species from France. Engel (1932) lists 82 Nearctic region and having a nearly world-wide dis-
Asilidae from Germany. Melin (1923) gives 25 species tribution Nearctiec region and in Central America
oe oe Far northern localities are likely to Neatetie cenion Wild 'in South. America ave their species totals increased by the abundance Total occurring in the Nearctic region of Cyrtopogon Loew and Laphria Meigen, abundant Central America only at higher latitudes. Lundbeck (1908) lists 28 species South America only : from Denmark. Efflatoun (1934, 1937) lists 88 species South America and in Africa ; Total occurring in Western Hemisphere from Egypt. aie : : 5 i South America, including those shared with North
The tabulation below attempts to show the extent of Roeiee ena ith A erica the fauna Asilidae for the larger land masses. It in- Nearctic region above Tropic of Cancer cludes all genera for each continent, for each northern Below Tropic of Cancer
segment above the Tropic of Cancer and treated col- lectively it shows the total genera for each vertical land conglomerate such as North and South America, Europe and Africa, and Asia with the Indo-Malayan, Papuan, and Australian regions. These areas yield
EUROPE AND AFRICA
Europe only
Palaearctie region and predominant there Holarctic region
World-wide, including Europe
some interesting, distributional facts. Most of the ire ue nee ana and ieee subgenera have been omitted from the totals of genera North Africa and Europe given below. Total occurring in Europe South Africa and Central Africa SNe geen KNOWN FROM VARIQUS/AREAS South Africa and also in Holarctic region
WESTERN HEMISPHERE Africa
Nearctic region only 39 Euro-African land mass
Nearctic region and in Europe, or Asia, or both 13 Above Tropic of Cancer
Nearctic region and in Africa 1 Below Tropic of Cancer
19
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3 16 82
105
4 196 125
66 141
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20 UNITED STATES
ASIA, INDO-MALAYA, PAPUA, AND AUSTRALIA
Asia above Tropic of Cancer
Asia, including those below Tropic of Cancer Below Tropic of Cancer, and including Australia Papuan region only
Australia only
Australia, exclusive of Papua
Australo-Asiatic land mass
NATIONAL MUSEUM BULLETIN 224
33 65 66 6 20 30 105
Tabulated below are the number of species of Asili- dae by subfamily according to standard world regions. I have largely followed Darlington (1957) in the selec-
tion of the boundaries of world regions.
The heavy
preponderance of species in the Neotropical region will be noted, as well as the large total for the western
hemisphere, which totals about 1874 species.
Dasypo- goninae Lepto- Mega- Laphri- Region gastrinae podinae inae Asilinae Total Nearctic 455 31 — 96 203 785 Neotropical 340 48 33 236 432 1089 Palaearctic 413 48 — 81 400 942 Ethiopian 326 36 — 117 803 782 Oriental 121 57 = 116 269 563 Australian 139 29 _- 99 172 439 Oceania 2 1 -- 4 7 14 Country unknown 88 2 — 14 66 120 The tabulation below shows the component genera
from the series of regional pockets, or concentrations of unique genera of limited range, which have been
discussed above.
It is not implied that the areas men-
tioned constitute absolute limits of the genera included, but rather that they represent approximately such regions and represent areas where such genera are
especially characteristic.
ASILID GENERA AND SUBGENERA FROM VARIOUS REGIONS
WESTERN UNITED STATES Ospriocerus Loew
Dicolonus Loew Bohartia Hull Zabrops Hull Willistonina Back Scleropogon Loew Callinicus Loew Coleomyia Wilcox and Martin Nannocyrtopogon Wilcox and Martin Fucyrtopogon Curran Metapogon Coquillett Itolia Wilcox Backomyia Wilcox and Martin Ablautus Loew Comantella Curran Lestomyia Williston Parataracticus Cole Atomosiella Wilcox Negasilus Curran
Wilcoria James
Megaphorus Bigot
Efferia Coquillett
INDIES
Lissoteles Bezzi Sphageus Loew Cystoprosopa, new
Opopotes Hull
DISTRIBUTION )
Ecthodopa Loew Neopogon Bezzi
Nicocles Jaennicke Tipulogaster Cockerell Bombomima Enderlein
EASTERN UNITED STATES
Ceraturgus Wiedemann Ceraturgopsis Johnson Dasylechia Williston CENTRAL AND SOUTH Orrhodops Hull Archilestris Loew
Dicranus Loew
TEXAS-OKLAHOMA AREA OF THE UNITED STATES
Bromleyus Hardy
Psilocurus Loew Lastaurus Loew
Hodophylar James
Omninablautus Pritchard Cerotainiops Curran Apachekolos Martin Beameromyia Martin
Proctacanthella Bromley
CENTRAL AMERICA AND WEST
genus
BHurhabdus Aldrich
NEARCTIC REGION (OF WIDER
AMERICA
Plesiomma Macquart
Blepharepium Rondani Schildia Aldrich Leptopteromyia Williston Lampria Macquart Smeringolaphria Hermann Rhopalogaster Macquart Pilica Curran Neophoneus Macquart Atractia Macquart Humecosoma Schiner Aphestia Macquart Senobasis Macquart Pseudoryclus Carrera Promachina Bromley Hicheragr Bigot
Lecania Macquart
NORTH ANDEAN (CORDILLERAN REGION )
Alyssomyia, new genus Zabrotica Hull Pholidotus Hermann Strombocodia Hermann Hybozelodes Hermann Lophoceraea Hermann Protichisma Hermann Bathropsis Hermann Oidardis Hermann Pronomopsis Hermann Ctenodontina Enderlein Lestophonaz, new genus
PATAGONIA, CHILE, BOLIVIA
Pritchardia Stuardo Obelophorus Schiner Hexameritia Speiser Dasypecus Philippi Dasycyrton Philippi Deromyia Philippi Lamprozona Hermann Automolina Hermann Philonerar Bromley Lochmorhynchus Engel Cratolestes, new genus Myapter, new genus Lycomya Bigot Chilesus Bromley Stizolestes, new genus Cratopoda, new genus Neodiogmites Carrera Cleptomyia Carrera Megonyz, new genus Tocantinia Carrera Dasyllis Loew Megapoda Macquart Doryclus Jaennicke
LA PLATA REGION
Helolaphyctis Hermann Macrocolus Bngel Tolmerolestes Lynch Arribilzaga Cylicomera Lynch Arribilzaga Prolepsis Walker Phonicocleptes Lynch Arribalzaga Acronyches Williston Caenarolia Thomson Lastauroides Carrera Mirolestes Curran Theromyia Williston Annamyia Protchard
PART 1
Aspidopyga Carrera Aczelia Carrera Enigmomorpheus Hermann Systellogaster Hermann Ichneumolaphria Carrera Alipiolaphria Carrera Hodites, new genus Othoniomyia Hermann Cyphotomyia Williston Rhathimomyia Lynch
Arribalzaga Dissmeryngodes Hermann Pseudorus Walker Hichoichemus Bigot Porasilus Curran Cerozodus Bigot Apotinocerus Hull Leptoharpacticus Lynch
Arribélzaga Leinendera Carrera Nyssoprosopa, new genus Anarmostus Schiner Threnia Schiner
SOUTH AMERICA (OF WIDER DISTRIBUTION )
Macahyba Carrera Triclioscelis Roeder Aporyria Schiner Lastaurina Curran Lastauraz Carrera Lastauronia Carrera Cyrtophrys Loew Aphamartania Schiner Austenmyia Carrera Paratractia, new genus Senoprosopis Macquart Glaphyropyga Schiner Epipamponerus Becker
COLOMBIAN AREA
Diplosynapsis Enderlein Cryptomering Enderlein Centrolaphria Enderlein
NORTH AND SOUTH AMERICA
Holcocephala Rondani Townsendia Williston Diogmites Loew Cophura Osten Sacken Atomosia Macquart Cerotainia Schiner Atoniomyia Hermann Mallophora Macquart Neraz, new genus Proctacanthus Macquart Becritosia Schiner Regasilus Curran Dizonias Loew
HOLARCTIC
Dioctria Meigen Myelaphus Bigot Haplopogon Engel Lasiopogon Loew Stenopogon Loew Cyrtopogon Loew Holopogon Loew Heteropogon Loew Cerdistus Loew Philonicus Loew Machimus Loew Epitriptus Loew Tolmerus Loew
INTRODUCTION
EUROPE ALONE (OR CHARAC- TERISTIC OF THAT REGION )
Leptarthrus Stephens Cycloscerus Bezzi Palamopogon Bezzi Pseudoholopogon Strobl Ecthistus Loew Rhadiurgus Loew
Brav Scopoli Pamponerus Loew Stilpnogaster Loew
PALAEARCTIC
Molobratia Hull Pycnopogon Loew Choerades Walker Satanas Jacobson EButolmus Loew Dysmachus Loew Acanthopleura Hermann Neomoctherus Osten Sacken
MEDITERRANEAN REGION, IN- CLUDING ARABIA
Torebroma Hull
Triclis Loew Glyphotriclis Hermann Scytomedes Hermann Acrochordomerus Hermann Rhadinus Loew Galactopogon Engel Briopogon Loew Habropogon Loew Anisopogon Loew Amphisbetetus Hermann Psilinus Wulp Dasypogon Meigen Paraphamartania Engel Ctenota Loew Paractenota Efflatoun Lowinella Hermann Eccoptopus Loew Polyphonius Loew Antipalus Loew
AFRICA MEDITERRANEAN RE- GION, INCLUDING AFRICA
Trichardis Hermann Sisyrnodytes Loew Acnephalum Macquart Oligopogon Loew Ancylorrhynchus Latreille Lamyra Loew Stiphrolamyra Hermann
CENTRAL AFRICA
Discodamalis Karsch Icariomima Enderlein Margaritola Hull Oxrynoton Jannsens Parorynoton Jannsens
ROBBER FLIES
Teratopus Loew Dolichoscius Jannsens Dinozabrus, new genus Heligmoneura Bigot
SOUTH AND CENTRAL AFRICA
Hoplistomerus Macquart Spanurus Loew Ammophilomima Enderlein Buscelidia Westwood Lasiocnemis Loew Dasyllina Bromley Storthyngomreus Hermann Proagonistes Loew Bnagaedium Engel Philomachus WKarsch
SOUTH AFRICA
Hermanella, new genus Laphystiella, new genus Gerrolasius Hermann Saucropogon, new genus Rhacolaemus Hermann Gonioscelis Schiner Daspletis Loew Oratostylum Ricardo Neodysmachus Ricardo Lagodias Loew Hobbyus Bromley Neolophonotus Engel Lophopeltis Engel Lophybus Bngel
AFRICAN, CAPE REGION
Lasiodamalis Hermann Lophurodamalis Hermann Dioctobroma, new genus Enagaedium Engel Philomachus Karsch Pegesimallus Loew Rhabdogaster Loew Lycostomus Hermann Anypodetus Hermann Sporadothriz Hermann Hippomachus Engel Megadrillus Bigot Synolcus Loew Dasophrys Loew Neodasophrys Ricardo Dysclytus Loew
AFRICA AND ASIA
Damalis Fabricius Microstylum Macquart Neolaparus Williston Lazenecera Macquart Hyperechia Schiner Goneccalypsis Hermann Apoclea Macquart Philodicus Loew Alcimus Loew
OF THE WORLD
AFRICA AND SOUTH AMERICA
Rhipidocephala Hermann Scylaticus Loew Hypenetes Philippi
Nusa Rondani
TRANSCAUCASUS
Hoplotricliis Hermann Perasis Hermann Udenopogon Becker Bremodromus Zimin Turkmenomyia Paramonov Crobilocerus Loew Jothopogon Becker Anarolius Loew Mecynopus Bngel Tranopogon Timon-David Amathomyia Becker Polysarca Schiner Polysarcodes Paramonov
CENTRAL ASIA
Oldroydia Hull
Toremyia Hull Hystrichopogon Hermann Merodontina Enderlein Trichomachimus Ricardo
SINO-FORMOSA AND JAPAN
Grypoctonus Speiser Sinopsilonyx Hsia Opeatocerus Hermann Hoplopheromerus Becker EHpiklisis Becker Oligoschema Becker Orophotus Becker
SINO-MALAYAN REGION
Damalina Doleschall Archilaphria Enderlein Lagynogaster Hermann Emphysomera Schiner Cophinopoda Hull
INDO-MALAYAN REGION
Aireina Frey Mesoleptogaster Frey Pagidolaphria Hermann Maira Schiner Michotamia Macquart Trypanoides Becker Clephydroneura Becker Astochia Becker Cinadus Wulp Haplonota Frey Strophipogon Hull
INDONESIA
Trigonomima Enderlein Astylopogon de Meijere Ophionomima Enderlein
21
Orthogonis Hermann Anisosis Hermann Anoplothyrea de Meijere Dichaetothyrea de Meijere Anacinaces Enderlein Amphiscolops, new genus
PAPUA AND CELEBES
Clinopogon Bezzi Epaphroditus Hermann Clariola Kertész Opocapsis Hull Despotiscus Bezzi Chymedar Hull Cenochromyia Hermann
EASTERN AUSTRALIA
Nerterhaptomenus Hardy Aplestobroma Hull Broticosia Hull
Psilozona Ricardo Chryseutria Hardy Codula Macquart Cryptopogon White Neoscleropogon Malloch Neodioctria Ricardo Harpagobroma, new genus Neocyrtopogon Ricardo Rachiopogon Ricardo Chylophaga, new genus Ateropogon Hardy Paraterpogon Paramonov Apothechyla, new genus Stizochymus, new genus Austrosaropogon Hardy Paptolestes, new genus Hrythropogon White Cabaza Walker Brachyrrhopala Macquart Thereutria Schiner Metalaphria Ricardo Cyanonedys Hermann Adelodus Hermann Neocerdistus Hardy
WEST AUSTRALIA
Opseostlengis White
Questopogon Dakin and Fordham
Dakinomyia Hardy
AUSTRALIA CONTINENT
Phellus Walker Chrysopogon Roeder Neosaropogon Ricardo Blepharotes Westwood Pararatus Ricardo Neoaratus Ricardo
AUSTRALIA, INCLUDING SOUTH AMERICA
Bathypogon Loew
Fossil Asilidae
A total of 39 species of fossil asilid flies are known at the present time, excluding the species Leptogaster erecta Meunier (1906) from Zanzibar copal. Several curious results are apparent from a consideration of these species and genera according to their separate horizons and subfamilies. The final definition of the genera in this family are to a very great extent based on characters other than wing venation, which makes many generic assignments problematical; but it is upon wing venation that an assignment of fossil flies must be made to the family and to the subfamilies of the Asilidae and this can be done with a high degree of accuracy. Consequently, in the check list of known fos- sil species here presented, I have used the names as- signed by the original authors with comments only where I myself have seen the type specimens. The scope of this generic study does not permit a complete review of the fossil asilid species.
We know fossil asilids from a single Eocene de- posit, the Green River shales, in which the family is represented by 2 subfamilies, 3 genera and 3 species. Among the 3 genera are 2 forms assigned to extinct genera. One of these is Stenocinclis anomala Scudder from the subfamily Dasypogoninae; another, Asilopsis fusculus Cockerell is from the Asilinae. The third species, Asilus palaeolestes Cockerell, was placed by Cockerell in a Recent genus. The scarcity of Eocene records in this family is much to be regretted.
In the Oligocene, it is notable that six deposits show asilids and that, while only one dasypogonine and one leptogastrine fly are known, no less than seven species of Asilinae in three genera have been described, besides two other examples referred to Ast/us Linné without descriptions.
In the Miocene the subfamily Leptogastrinae is known by two species from two deposits. The Dasypo- goninae are represented by 13 species in 10 genera; of these generic assignments 6 were made by Cockerell and 3 by James. The Miocene Dasypogoninae all come from deposits in the Miocene Florissant of Colo- rado, with one exception from Radoboj and one from the Ruby Basin of Montana. Also, no less than 12 species of Asilinae have been described from two Mio- cene deposits, the Florissant of Colorado and Oeningen. These 12 species of Asilinae, according to their authors, fall into 3 genera. No fossil fly of the subfamily Laphriinae is yet known from any formation.
In connection with fossil Asilidae it should be noted that Bode (1953) has described and figured Yoasilidea fragmentosa Bode (1953) which he calls the type of a new family, the Eoasilidae. As I have not seen this
22
fossil fly I can not comment on it, except to point to the apparently large number of crossveins in both this and his other new genera and families. In many of these he shows 30 or more crossveins. The material was reported from the Upper Lias.
From the fossil asilids what general conclusions, if any, are we entitled to draw concerning the origin of the family Asilidae? First, we must put the origin of the family before the Eocene. Second, there is, perhaps, an understandable dearth of fossils from the Eocene, but in any case the two principal subfamilies make their appearance in this horizon. There is a less understand- able dearth of fossils of the subfamily Dasypogoninae from the Oligocene, inasmuch as five deposits show asilids with only one representative of the Dasypo- goninae among the eight known species. The greater number of these Oligocene species come from the Baltic amber. This is a medium that could be expected to trap both of these main subfamilies to about an equal extent. Since I believe that we are obliged to accept the conclu- sion that the Dasypogoninae and Leptogastrinae both antedated the higher and more specialized Asilinae, it is all the more peculiar that we have thus far not found Dasypogoninae in abundance as fossils in pre-Miocene formations. The explanation may well be that not until Miocene times were the flies of this family differentiated out into a multiplicity of types. On the other hand, fu- ture collections of fossil flies may increase the number of genera and species known from lower horizons. Thus far, of the known species and genera, it is interesting to note an approximate threefold increase in species from the Oligocene over the Eocene, and a threefold in- crease of species and genera as well, in the Miocene over the Oligocene.
- In the Dasypogoninae are to be noted three tribes, of which one is the Dioctrini with two species; in this study this tribe is assigned a key position as the most generalized of all tribes within the subfamily. Of the remainder, which fall into the Dasypogoninae, we note that five species occur in the Stenopogonini or “simple tibia” group, with the anterior tibia not spined at apex, and five in the Dasypogonini. Recent genera with non- rotate male terminalia are not represented. Of them all, only the species of Déoctria Meigen represent genera in which the female lacks acanthophorite spines.
In a comparison of the fossil species assigned to Recent genera and compared with present day forms, we are frequently able to note small but interesting changes in the wing venation suggesting subgeneric status in some cases. I erected a subgenus Hosenopro- sopis Hull (1957) for two of the fossil species of Seno-
INTRODUCTION
prosopis Macquart. James (1939) has commented on venational differences in his species Ceraturgopsis praecursor James.
Genera Known Only From Fossil
The following genera are known only from fossils:
Genus Stenocinclis Scudder Figure 2536
Stenocinclis Seudder, Rep. U.S. Geol. Surv. Terr., vol. 13, p. 563, 1890. Type of genus: Stenocinclis anomala Scudder, 1890, by monotypy.
I quote Scudder’s description :
This genus is founded wholly upon characters drawn from the neuration of the wings, the only portion of the insect preserved. It falls into the group of Dasypogonina, in which the second longitudinal vein terminates on the margin apart from the first longitudinal vein instead of uniting with it just before the margin. It is not very far removed from Dioctria Meigen but differs from it and all Asilids I have examined in that the third longitudinal vein arises from the first before the middle of the wing, instead of from the second longitudinal vein after its emission from the first; the first longitudinal vein has therefore 2 inferior shoots, giving the wing a very peculiar aspect; indeed it would be hard to know where to look for a similar feature among allied Diptera unless it would be in the anomalous group of Cyrtidae. The wing is very slender and all the cells unusually elongated which also gives it a very unique appearance.
In the figure the curve of the presumptive anterior branch of third vein is similar to any one of several genera, as for example, Saropogon Loew, Laphystia Loew, Dioctria Meigen.
Genus Asilopsis Cockerell FIGURE 2535
Asilopsis Cockerell, Proc. U.S. Nat. Mus., vol. 57, pp. 250-251, 1920. Type of genus: Asilopsis fusculus Cockerell, 1920, by original designation.
I quote from Cockerell’s descriptions of Asdlopsis and A, fusculus, as follows:
Small flies apparently related to Asilinae or Laphriinae; marginal cell closed far from end of wing; base of marginal obtuse, and the part basad of basal end of first submarginal much longer than that apicad of it; first basal on first sub- marginal scarcely longer than anterior cross-vein; discal cell elongated, with anterior cross-vein far toward the base; two submarginal cells, the second less than half as long as the first; second posterior cell somewhat swollen towards base; fourth posterior apparently open. ... The dark cloud in the apical part of the marginal cell is suggestive of Leptidae, and is not an asilid character. It is possible if we had the whole fly a distinct family would be indicated, and on the wing alone it seems justifiable to establish a subfamily Asilopsinae.
Cockerell calls attention to a dark cloud at the end of the marginal cell, speaking of it as a leptid char- acter. Cockerell’s whole genus is based upon a wing only, and I should like to point out that a dark, stigmal spot near or associated with the apex of the marginal cell is also characteristic of some stratiomyids, as AJ- lognosta Osten Sacken and Beris Latreille. Since the
535914—62—pt. 1-3
ROBBER FLIES OF THE WORLD 23
first and second veins end so close together in Xylopha- gus Meigen, it would not require any great change to derive from it a wing very similar to Asi/opsis Cock- erell. Apart from the peculiar, marginal cell the vena- tion is a great deal like some species of Cyrtopogon Loew and Yoremyia Hull. Since it is possible to pick out rhagionid wings not too far removed from asilid wings, the ultimate interpretation of Asilopsis Cock- erell must rest upon the presence or absence of a pro- boscis and the character of the pretarsus. Without further material and for the reasons given above, I reject a subfamily based upon this fly.
Subgenus Eosenoprosopis Hull
Hosenoprosopis Hull, Psyche, vol. 64, no. 2, p. 42, 1957. Type of subgenus: Senoprosopis romeri Hull, 1957, by original designation.
Wing with no posterior crossvein, the veins at end of second basal cell crossed and the fourth posterior cell with no petiole at its base. Anterior branch of third vein ends clearly at the apex of the wing, as in Opopotes Hull, a Recent genus. It appears to be in- termediate between Opopotes and Senoprosopis Mac- quart.
I wish also to comment upon the assignment of Seno- basis antigua James, since I have examined the type. In the type the preservation of the apex of the right fore tibia is excellent; it shows a weak spine or tibial process with no basitarsal modification and is in very much contrast to the pronounced and remarkable pro- tuberance present in all species of Senobasis Macquart today with their accompanying flangelike process of the basitarsus. I consider it more likely that the fly in question is related to Lestomyia Williston. I therefore propose for Senobasis antiqua the new genus Palaeomo- lobra with type of genus antiqua James.
Palaeomolobra, new genus
Type of genus: Senobasis antigua James, 1939.
This genus is defined by the weak spine on anterior tibia, the widely open marginal cell and the closed fourth posterior cell with the posterior intercalary vein strongly convex.
Checklist of Fossil Asilids
The list below gives by subfamily the known species and genera of fossil asilids and is believed to be com- plete as of 1953. References are included in the gen- eral bibliography.
FROM EOCENE FORMATIONS DASYPOGONINAE Stenocinclis anomala Scudder, 1890. Green River shales. ASILINAE
Asilopsis fusculus Cockerell, 1920. Green River shales. Asilus palaeolestes Cockerell, 1921. Green River shales.
24
FROM OLIGOCENE FORMATIONS Asilidae Helm, 1896. Baltic amber, Germany.
DASYPOGONINAE
Holopogon pilipes Loew, 1850. Baltic amber, Bernstein fauna, Germany.
LEPTOGASTRIN AE
Leptogaster falloti Theobald, 1937. Camoins, France.
ASILINAE
Proctacanthus fractus Cockerell, 1921. Isle of Wight.
Asilus klebsi Meunier, 1908. Baltic amber, Germany.
Asilus sannoisiensis Meunier, 1915. Aix in Provence, France.
Asilus gurnetensis Cockerell, 1921. Isle of Wight.
Asilus angustifrons Loew, 1850. Baltic amber, Bernstein fauna, Germany.
Asilus trichurus Loew, 1850. Baltic amber, Bernstein fauna, Germany.
Asilus sp. Serres, 1829. Aix in Provence, France.
Asilus sp. Heyden, 1870. Lignite beds of Rott, Siebengebirge at Bonn, Germany.
Machimus kollmanni Timon-David, 1944. Basin of Marseille, France.
FROM MIOCENE FORMATIONS Asilidae Scudder, 1881. Florissant shales, Colorado.
DASYPOGONINAE
Holopogon archilestes Hull, 1960. Ruby Basin, Montana.
Dioctria? florissantina Cockerell, 1909. Florissant shales, Colorado.
Dioctria? pulveris Cockerell, 1917. Colorado.
Nicocles miocenicus Cockerell, 1909. Florissant shales, Colorado.
Taracticus contusus Cockerell, 1910. Colorado.
Taracticus renovatus Cockerell, 1911. Colorado.
Florissant shales,
Florissant shales,
Florissant shales,
UNITED STATES NATIONAL MUSEUM BULLETIN 224 PART 1
Cophura antiquella Cockerell, 1913. Florissant shales, Colorado.
Saropogon oblitescens Cockerell, 1914. Florissant shales, Colorado.
Microstylum wheeleri Cockerell, 1908. Florissant shales, Colorado.
Microstylum? destructum Cockerell, 1909. Florissant shales, Colorado.
Lestomyia miocenica James, 1939. Colorado.
Ceraturgopsis praecursor James, 1939. Florissant shales, Colorado.
Palaeomolobra borealis James, 1939. Florissant shales, Colorado.
Florissant shales,
LEPTOGASTRINAE
Leptogaster hellii Unger, 1839. Marls of Radoboj, Croatia. Leptogaster prior Melander, 1946. Florissant shales, Colorado.
ASILINAE
Asilus amelanchieris Cockerell, 1911. Florissant shales, Colo- rado.
Asilus wickhami Cockerell, 1914. Florissant shales, Colo- rado.
Asilus peritulus Cockerell, 1909. Florissant shales, Colorado.
Asilus curculionis Melander, 1946. Florissant shales, Colo- rado.
Asilus florissantinus James, 1939. Florissant shales, Colo- rado.
Asilus bicolor Heer, 1849. Oeningen shales, Germany.
Asilus antiquus Heer, 1849. Oeningen shales, Germany.
Asilus deperditus Heer, 1849. Oeningen shales, Germany.
Philonicus sarorum James, 1939. Florissant shales, Colo- rado.
Senoprosopis (Hosenoprosopis) antiquus James, 1939. Flor- issant shales, Colorado.
Senoprosopis (Hosenoprosopis) romeri Hull, 1957. Floris- sant shales, Colorado.
Senoprosopis eureka Melander, 1949. Florissant shales, Colorado.
10.
11
12.
13.
14,
. Alula absent .
. Males with 8 tergites.
. Style of antenna plumose .
Family Asilidae
KEY TO SUBFAMILIES AND TRIBES OF ASILIDAE
. Palpus of l segment. . . 2
Palpus of 2 segments (with sometimes ‘the ‘vestiges of a URI esepMent) rads Gettiee Ke cel ola bese 2) se LO
meVianoinalicelliclosedis ciyet cleat, ’) foie Bisse availa ee nD
Marpinalycelopen. sured a) as. 2 aah kei hae, eo iy seein (8 Sera olay ists LEPTOGASTRINAE Alula present ... 4
. Third antennal segment. spindle-shaped, with apical n micro-
segment; fourth posterior cell generally open or closed in the margin; the anterior medial mesonotum extends into the pronotum. Females with terminal spines (Neolaparus Williston) . : . . DASYPOGONINAE Third antennal segment clavate, with only apical pit; fourth posterior cell generally, if not always, closed and stalked; anterior medial mesonotum not extended into pronotum (Senobasis Macquart) MeGAPODINAE
. Terminal segment of antenna bears a long, slender, arista-
form style, with or without minute, intermediate microseg- ments (Asilinae) . 5 meet rend oD) Terminal segment without : a long, slender style aie cir
. Foretibial apex with a strongly developed protuberance and
spine; anterior basitarsus with a stout flange; dorsal and ventral components of male terminalia united at base. MEGAPODINAE Foretibial apex with simple bristles only . . . dh Females with abdomen elongate, tapering, attenuate, rarely broad and flattened. . . 8 Males with 7 tergites. Females without ovipositorial spines. Flies with blunt claws, form short and robust or with elongate, subclavate abdomen and long legs. CTENOTINI
. Third antennal segment very long and slender, with short
bristle bearing microsegment; females without ovipositorial spines (Glaphyropyga Schiner, Chilesus Bromley, Lycomya Bigot) nae 5 ASILINAE Third antennal segment short, dilated or widened subapically, without a short, slender style. Female acanthophorites with a prominent circlet of several pairs of stout, sharp spines. . ENIGMOMORPHINI OMMATINI Style of antenna simple . . . . ASILINI Marginal cell closed and petiolate, ¢ or ‘closed | in the margin
eee ene (.w
of the costa . . ee oe tenor ee ee
Marginal cell open (Dasypogoninae) arcane eee Anterior tarsal apex with spine (Dasypogoninae).
THEREUTRINI
Anterior tarsal apex simple . . 6
Marginal cell with a distinct and well “developed stalk or petiole and never with the second vein recurrent (Laphriinae) . els
Marginal cell without : a petiole, or rif a very short petiole i is present the second vein is nes recurrent (Dasypogo- ninae) Sy : : LAPHYSTINI
Postmetacoxal area chitinized; or if rarely unchitinized (Paratractia, new genus) a dorsal, antennal spine is present . . OO . ATOMOSINI
Postmetacoxal a area membranous eat be V4
Palpal end segment cylindroid. Proboscis usually laterally compressed, never flattened dorsoventrally . LaAPHRIINI
15. 16.
lhe
18.
il). 20.
21.
22. 23.
24,
25.
End segment of palpus hemicylindroid and excavated Proboscis usually compressed dorsoventrally, at least at apex; never flattened laterally ANDRENOSOMINI
Notopleuron with a stout spine CHRYSOPOGONINI
Notopleuron with bristles only . . LO
Lateral slopes of metasternum without pile. " Vertex ex- panded and usually greatly widened. Second palpa segment usually small, cylindrical, with few hairs or none. Apex generally truncate. With few exceptions small or even minute flies. . . + . . STICHOPOGONINI
Lateral slopes of metasternum with pile Sf etneens ns) Le
Palpus very large, the second segment exceptionally long and bristly. Anterior branch of third vein near its base with a spur vein. Hi and often extremely large Hiest ie ists . PHELLINI
Palpus small, often “minute. " Anterior branch of ‘third vein very rarely with a subbasal spur. Small to medium size flies, more rarely large . . . Meow cre teomeeS
Head exceptionally wide and short, unflattened on anterior aspect; vertex low, leaving a “gogsle-eyed” aspect. Small or at most medium size flies . DAMALINI
Head eae erie ceeen andswidth <-\) en neenne tans LD
Malesyi es SPaeKs se Mant. amie unPatee cO
Females .. ake 20
Tergites distinctly limited ' to six; lateral tergal margins often with stout bristles. . é . LAPHYSTINI
More than 6 tergites developed, or . if only six (Nicocles Jaennicke) the last two are greatly flattened with dense, silvery micropubescence . . See
Eighth tergite developed and a ‘vestige of the antepenulti- mate palpal segment usually present. Antennal segments 4 to 6 in number. Terminalia usually not or only partly rotate. Gonopods and lateral apices of the sulcate epandrium often with long, lobe-like processes. Dorsal pronotum with fine pile or bristly hairs. Occiput without strong bristles. Apex of anterior tibia never with spine.
Dioctrint
Highth tergite usually limited to a trace. Only 2 tarsal segments present. Antennal segments 3 and 4 often with apical spine. Terminalia usually rotate, except in Steno- pogon Loew and allies. Dorsal pronotum and occiput generally with strongly differentiated bristles . . . . 22
Anterior tibia never with spine at apex . STENOPOGONINI
Anterior tibia always with spine at apex . DaAsYPOGONINI
Terminalia with a quarter-circlet of spines on each acantho- phorite. These spines sometimes small, obscure and re- cessed (Brachyrrhopala Macquart, Cabaza (Walker) . 24
No spines present on female terminalia. . ...... 25
Anterior tibia never with spine present at apex.
STENOPOGONINI
Anterior tibia always with spine at apex . DASYPOGONINI
Prosternal sclerites free from the pronotum. Lateral epistomal creases continued to the rear of the occiput. Tergites, except the first, never with differentiated bristles.
Droctrini
Prosternum fused to the pronotum. Lateral epistomal creases closed behind, tending to leave a pit anteriorly. Tergite with or without strong bristles laterally.
LAPHYSTINI
25
26 UNITED STATES NATIONAL MUSEUM BULLETIN 224
PART 1
Subfamily Dasypogoninae
Five tribes of Dasypogoninae are regarded as being essentially generalized. All lack the acanthophorites and their accompanying spines. These tribes are the Dioctrini, Phellini, Chrysopogonini, Damalini and the Laphystini. Five other tribes have present the circlets of stout spines on the acanthophorites of the ninth ter- gite in the female sex. In this group we find the Dasy- pogonini, with the Stenopogonini and the small groups of Stichopogonini, Enigmomorphini, and Thereutrini.
Some interesting zoogeographic relationships are to be found. The Dioctrini occur sparingly in all world regions, poorly in Asia, Australia, Ethiopia and South America. The Chrysopogonini and Thereutrini are re-
stricted to Australia. The Phellini are restricted to Australia and Chile. The Damalini are most numerous in southern Asia and the northern Neotropical region. They are absent from Europe proper and are poorly represented in Australia, if at all, but are found in Ethiopia. The Laphystini are world wide, but scarce in southern South America and in Australia; they are best developed in the Holarctic region. The Stichopo- gonini are almost world wide but seem to be very poorly represented in the Neotropical region. The Dasypo- gonini and the Stenopogonini are both world wide. Endemic genera will be mentioned in the discussion of the several tribes.
Tribe Dioctrini
Here are placed those Dasypogoninae, excepting Phellus Walker, Damalis Fabricius, Laphystia Loew, Chrysopogon Roeder and their allies, in which the fe- male ninth tergite is generalized and lacks acanthopho- rites and spines. The genera which fall here are few in number, but they appear to be most generalized of all present day Asilids which have a simple ovipositor. Two species of fossil flies from the Miocene of Colorado have been referred to Dioctria Meigen with a question, by Cockerell (1909, 1917). The marginal cell is widely open and all of the posterior cells are widely open, ex- cept in Pritchardia Stuardo and Aplestobroma Hull, where the fourth posterior cell is closed and stalked. Palpus always with 2 segments and sometimes with a distinct trace of the antepenultimate segment. Because of certain general similarities in construction, it is pos-
sible that Brachyrrhopala Macquart and its allies such as Austrosaropogon Hardy and even Lrythropogon White may have been derived from the ancient Dioc- trini, and of course the same may be true of all higher members of the subfamily. The construction of the head in the Laphystini also shows a similarity in the Dioctrini. The flies of this group are restricted to the Holarctic region, except for the remarkable Australian genus Nerterhaptomenus Hardy, which appears to be- long in this tribe. Several sketches were included with the original description. The types are reported to be lost. Although I made a special search while in Bris- bane at the proper season in 1953, I was not able to collect new material of this genus. The outlying part of this city is the type locality for this genus.
KEY TO GENERA OF DIOCTRINI
1. Anterior tibia with a spine at apex; female terminalia without spines. .... CA Ronrol Dis pl 8 cop Cel RR Anterior tibia without trace oF sate or eeaines re 2. Apical spine of anterior tibia attached to a long, stout, apical process. Anterior tibia and tarsus unusually long. Male hind basitarsus not different from the female. Male abdomen with 7 tergites; female with 8 tergites; acantho- phorites and spines absent. Third antennal segment with dorsal setae and short, stout, spine-tipped microsegment. Mocopratia Hull Anterior tibia without apical process, the spine weak and curved. Anterior tibia and tarsus not of unusual length. Hind basitarsus in male as long or longer than tibia, flattened, slender, attenuate. Female basitarsus swollen and elongate. Face convex and rather densely long, fine pilose, without stout mystax bristles. Male abdomen composed of 7 segments; female of 5 segments, with the remainder forming a tubular, flattened ovipositor. Third
antennal segment long, slender and attenuate with a long microsegment and thick, short style.
LeptartHrus Stephens
3. Metanotal callosity with stiff pile or bristles. Dicotonus Loew Metanotal callosity bare or micropubescent only. . .. 4 4, Antenna unusually elongate, usually 2 times as long as the head, and the third segment bearing 2 eee: stout and conspicuous microsegments . . 5 Antenna 1 to 1% times as long as the ‘head, or ‘if ‘of greater length there is only a single microsegment present. . . 7 5. Second antennal segment quite short and beadlike and only one-fourth to one-sixth as long as the first segment; micro- segments of third antennal segment peculiarly constructed and unusually prominent . . A 6 Second antennal segment very little shorter ‘than the first; microsegment of the third segment distinct but not prom- inent. Lower half of face gibbous and bearing dense, long, slender bristles; posterior femur with stout, tubercu- late bristles ventrally. ....... Ecutuopora Loew
DASYPOGONINAB
6. Face unusually wide; the front and vertex, beginning opposite the antenna, are greatly expanded and divergent; apex of third antennal segment and apex of first microsegment without deep, conspicuous clefts.
HERMANNELLA, new genus
Face approximately one-third of the head width or less; beginning below, the face is slightly convergent and this convergence continued at the same rate to the vertex. Apex of third antennal segment and first microsegment with deep clefts in which is received the attachment of the next succeeding segment .. . . . MyenapuHus Bigot
7. Fourth posterior cell closed and stalked Ld Sesieespe g 'r (8
Fourth posterior cell widely open. . . 9
8. Head in frontal aspect as high as wide and therefore nearly circular; face narrow and its width not more than one- seventh the head width; third antennal segment slender; face nowhere prominent and only “ee produced below; anal cell open... vom 8A
Head in frontal aspect wider than high; face little less than one-fourth the head width; third antennal segment much swollen and dilated. Anal cell closed and stalked.
PRITCHARDIA Stuardo
8a. Disc of scutellum bare, or with 1 or 2 minute hairs. Fe-
male terminalia enclosed by a cylindroid jacket with wide
terminal orifices. Male terminalia rotate, bearing a long, medial (dorsal), stout prong from the hypandrium.
APLESTOBROMA Hull
Dise of scutellum with long, bushy pile. Female unknown. Male terminalia rather similar to Aplestobroma Hull.
PEGOLABRUS, new genus
9. Head wider than high. Front and antennal base more or less swollen, leaving the face usually concave, more rarely a little convex. Third antennal segment often with bristles (Dioctria Meigen sensu lato). ....... 10
Head circular, no wider than high. Face exceptionally narrow, one-tenth of head width and divergent below. Face pile exceptionally long and straight and stiff and confined to a narrow, medial row. Fourth posterior cell widely open; male with terminalia similar to A plestobroma Hull, the dorsal (inverted) prong much wider. Female unknown Mee beuie ete ora Broticosra Hull
Genus Dioctria Meigen
Ficures 2, 9, 397, 403, 802, 811, 1633, 1634, 1885 1936, 1963, 2020
Dioctria Meigen, Mag. Insektenkunde, vol. 2, p. 270, 1803. Type of genus: Asilus oelandicus Linné, 1758. Designated by Latreille (1810) the first of 3 species.
Methylla Hansen, Naturh. Tidsskr., ser. 3, vol. 14, pp. 145, 198, 1883. Type of genus: Dioctria humeralis Zeller, 1840, by original designation.
Dioctria has 3 subgenera, Hudioctria Wilcox and Martin, Metadioctria Wilcox and Martin, Nannodioc- tria Wilcox and Martin.
Small or medium size flies, characterized by the elon- gate, comparatively slender abdomen, in the female without spines or acanthophorites on the ninth tergite; male terminalia not rotate and epandrium without for- ceps. The abdomen is sometimes slightly clavate and tends to be corrugate on the dorsal aspect of the basal segments. Face almost plane, or slightly bulbous be- low, or with only the middle portion plane. Face, ex- cept in a few instances, characteristically protuberant at and just below the base of the antenna. Antenna at- tached usually near the vertex; the front, therefore, short; antenna elongate, slender, with apical, spoon-
ROBBER FLIES OF THE WORLD 27
10. Third antennal segment bearing 2 long microsegments, together nearly as long as the third segment and with apical spine. Male terminalia large, obtuse, clublike. Hind metatarsus swollen . . NeRTERHAPTOMENUS Hardy
Third antennal segment with a single, obtuse, spoon-shaped microsegment and enclosed spine. Male terminalia short, inconspicuous. . . Se eee:
11. Hind tibia slender, pieseaie oa ae the Apical part en- larged; hind metatarsus enlarged, elongate, or both, and longer than second and fourth segments together. Scutel- lum more or less convex and bearing short, recumbent, discal and marginal pile. Anterior branch of third vein reaching wing margin at or below the apex of the wing. Wings elongate, narrow, with the axillary cell and alula greatly reduced insize. ... thet seg ke
Hind tibia normal, in some species ‘slightly narrowed on the basal half; hind metatarsus normal and subequal in length to second ‘and fourth segments together. Scutellum more or less flattened, bare on the disc, with long, erect, mar- ginal hairs. Anterior branch of third vein reaching anterior margin before the apex of the wing. Wings normal or very broad, the axillary cell and alula well developed .... a ee als
12. First antennal peemiene ieaeee eae the cea third of uniform width and the style about equal in diameter to the third segment. Face concave, the oral margin and antennal base more or less prominent . Dirocrria Meigen
First and second antennal segments nearly equal in length, third narrow basally and quite broad in the middle, the style minute. Face in profile slightly convex, the oral margin and the antennal base not at all prominent (subgenus of Dioctria Meigen).
Nannoptocrria Wilcox and Martin
13. Seutellum bare of pile. Hind femur and tibia and usually the middle and anterior ones with numerous, small, setigerous tubercles below (subgenus of Dzoctria Meigen).
Evptocrria Wilcox and Martin
Scutellum with quite numerous, long, erect, marginal hairs. Femur and tibia without setigerous tubercles (subgenus of Dioctria Meigen) . Meraptocrria Wilcox and Martin
shaped microsegment enclosing a spine. All cells of the wing open, usually widely open. Length 8 to 20 mm.
Head, lateral aspect: Face plane, level with the eye in the middle of the face, gently rounded and slightly pro- tuberant on the lower third and rather strongly pro- tuberant on the upper third. Occiput short, a little more prominent below, becoming a little thicker towards the middle of the head; pile stiff and bristles moder- ately abundant below; stout bristles begin at the lower third, curve slightly forward and consist of 25 or more pairs, some of which are rather strongly curved. Pro- boscis stout, strongly swollen at the base, pointed api- cally, rounded and curved on the ventral aspect, sub- quadrate on the apical third which bears a conspicuous tuft of stiff dorsal pile. Ventral surface with a deep longitudinal fissure throughout its length; base below with a tuft of stiff bristles. Proboscis usually directed forward. Palpus clearly of two segments, the first seg- ment hemicylindroid, but distinctly fused; second seg- ment not porate, cylindrical with numerous stout bristles. Antenna usually attached at or above the up- per eighth of the head, or in the subgenus Hudioctria Wilcox and Martin, attached just above the upper third. Antenna elongate, distinctly longer than the head; seg-
28 UNITED STATES NATIONAL MUSEUM BULLETIN 224
SF is ae eee
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Text-Ficure 8.—Pattern of distribution of the genus Dioctria Meigen.
ment one is longer than the second; third segment, including microsegment, as long or longer than the first two segments combined and of approximately the same width. Third segment subcylindrical, slightly nar- rowed at the apex, and bearing a long, wide apically rounded, pubescent, spoon-shaped microsegment, which carries a distinct basal spine. First two segments with numerous, appressed, stiff, rather long bristles both on the dorsal and ventrolateral surfaces; third segment with several appressed, dorsal bristles. In some species the first two segments may be nearly equal in length; in subgenus H'udioctria the antennae are still elongate, though all segments are reduced, including the third.
Head, anterior aspect: Face between antennae one- fourth the head width and slightly divergent below; subepistomal area large, slightly oblique or rarely small and strongly oblique. Face micropubescent laterally and below, but often bare beneath the antenna and in the middle of the face; pile absent and bristles con- fined to a rounded cluster covering the lower facial eminence, containing more than 20 stout, curved bristles, or with only a single transverse row of 4 pairs. Front generally very short, polished and bare, in Eudioctria pollinose with a conspicuous row of rather long slender bristles along the ocular margin. Vertex moderately excavated; ocellar protuberance high with
steep sides, and a few minute, short, anteriorly directed bristles confined to the posterior region, or in H'udioc- tria with 4 or 5 pairs of long, slender, central bristles. Eye facets at most slightly enlarged.
Thorax: Low, gently curved, shining, often with pubescent vittae. Pleuron chiefly shining, with spots or diagonal bands of appressed pubescence. Pile of mesonotum rather scanty, erect and bristly; acrostical band present; dorsocentral bristles moderately distinct but rarely long. In the type of the genus the following complement of long, slender bristles present : One noto- pleural, 7 supraalar, 8 to 10 short postalar, no scutellar bristles. Scutellum flat, its margin often with a wide band of fine bristly hair and similar discal hair or disc bare. The margin almost without pile in Dioctria al- bius. In the type of genus the pleuron anteroventrally has a tuft of long stout curved bristles; in H'udioctria with pile only. Pronotal collar sometimes with bristles. Typically the posterior margin of the meso- pleuron has a vertical row of weak bristles; metapleu- ron with 6, 7, or 8 bristles; remainder of pleura apilose. Metanotal callosity pubescent only. Ventral and lateral metasternum with pile; postmetacoxal area membranous,
Legs: All the femora moderately lengthened, the hind femur not quite twice as wide distally as basally.
DASYPOGONINAD
The legs bear dense, short, appressed setae dorsally. The ventral surfaces of the femora and tibiae with a dense, erect fringe of moderately long pile. Tibial setae brush restricted to apex. Bristles are compara- tively few, more numerous on the middle and hind legs, and are short but rather stout. The type of genus bears the following complement of bristles: hind femur with 2 or 3 lateral bristles near the base, 2 to 4 others medially on the basal half, apex with 1 lateral, 1 dorsal, and 2 medial bristles. This tibia bears 5 dor- solateral, 5 to 7 dorsal; apex with 2 dorsal, 2 lateral, 2 or 3 medial and 5 or 6 ventral bristles. Middle femur with 3 or 4 fine, short bristles posteriorly, 4 at the apex and 10 or more short bristles laterally. This tibia bears 4 anterior, 5 or 6 posterior and 5 dorsal bristles, all short and stout. Anterior femur with posteriorly a bristle in the middle, a posterior cluster of 3 at the outer third and the same apical bristles as the middle femur; this tibia bears 6 short dorsal, 6 longer poste- rior ones, 4 slender ventral bristles. Protibial apex without spine. Claws sharp; pulvillus may be half as long as claws or well developed. Empodium long.
Wings: Marginal cell and all posterior cells widely open; second basal cell ends in three veins. Anal cell widely open in the sixteen species before me. Alula quite short, the ambient vein complete.
Abdomen: The abdomen is elongate, rather slender subbasally, often subclavate, characteristically bare and polished, with very short, fine, suberect, scanty pile. Males with 8 tergites, the eighth only one-fifth as long as the seventh. Females with 8 tergites, the last one- third as long as the seventh. Segments 2 to 5 distinctly elongate and each longer than wide. Bristles absent, except on the first tergite, where they are weak. Male terminalia moderately large, not rotate, the epandrium undivided, but often as in the subgenus Hudioctria Wil- cox and Martin, with a deep, wide or narrow cleft and lateral lobes, or sometimes with apical tooth or hair tuft, and with short, lateral spur. Hypandrium very short; gonopod large, rounded and convex and gen- erally lobate at apex. Female terminalia very short, divided dorsally and without spines.
The flies of Dioctria are weak flying species that characteristically associate with the leaves of low undergrowth and shrubs or herbs and are often about alders.
The flies of the genus Dioctria, sensu lato, are Holarctic in distribution. Some American species are dimorphic. The introduced European species Déoc- tria baumhaueri Meigen is found in the eastern United States. There is a dense concentration of species in eastern and central Europe, and on the Pacific coast of the United States. Probably the three species de- scribed from each of the Neotropical and Ethiopian regions and certainly the two Australian species belong elsewhere; Dioctria tenuis Walker appears to belong to the genus Mirolestes Curran. The Nearctic species have been reviewed by Wilcox and Martin (1941).
Distribution: Nearctic: Dioctria albicornis Wilcox and Martin (1941) ; albtws Walker (1849), albius auri-
ROBBER FLIES OF THE WORLD 29
facies Wilcox and Martin (1941), albius wanthopennis Wilcox and Martin (1941); banksit Johnson (1918) [=longicornis Banks (1917), not Meigen], banks tibi- alis Wilcox and Martin (1941); beameri Wilcox and Martin (1941) ; brevis Banks (1917) ; doanei Melander (1923) ; henshawi Johnson (1918) [=flavipes Banks (1917), not Meigen]; media Banks (1917) ; monrovia Wilcox and Martin (1941); nitida Williston (1884), nitida denuda Wilcox and Martin (1941); parvula Coquillett (1893) ; plewralis Banks (1917) ; propingua Bromley (1924); pusto Osten Sacken (1887); re- splendens Loew (1872); rubéda Coquillett (1893), rubida nigripilosa Wilcox and Martin (1941), rubida atripes Wilcox and Martin (1941); sackeni Williston (1884), sackent rivalis Melander (1923); seminole Bromley (1924); vera Back (1909); vertebrata Cole (1919).
Neotropical (allocation dubious): Déioctria nigrita Fabricius (1805) ; tenwis Walker (1851); vicina Mac- quart (1838).
Palaearctic: Dioctria abdominalis Becker (1923) ; arthritica Loew (1871); atricapilla Meigen (1804) [=atrata Wiedeman in Meigen (1820), fal/ent Meigen (1820), fuscipennis Fallen (1814), fuscipes Gimmerthal (1847), geniculata Meigen (1820), nigripes Meigen (1804) ], atricapilla rufimana Loew (1840) ; atrorubens Séguy (1930); baumhaueri Meigen (1820); berlandi Séguy (1927); bécineta Meigen (1820) [= ?annulata Meigen (1820), infuscata Meigen (1820) ]; bigot: Costa (1884) ; caesta Pallas in Wiedemann (1818) ; calceata Meigen (1820), calceata nigriventris Strobl (1902) ; cavifrons Enderlein (1934); claripennis Villeneuve (1908); conspicua Becker (1923); contraria Becker (1923) ; cothurnata Meigen (1820) [=meigent Shuck- ard (1841), wmbellatarum Meigen (1820)]; cretensis Becker (1923) ; dispar Loew (1871) ; flavicincta Roeder (1884) ; favipennis Meigen (1820) [=aurifrons Meigen (1820) ]; fuscipes Macquart (1834) [=melanopa Egger (1859), melanopogon Schiner (1862) ]; gagates Wiede- mann in Meigen (1820) [=semihyalina Wiedemann in Meigen (1820), vedipus Loew (1869) ], gagates stria- tipes Becker (1923) ; gracilis Meigen (1820) [=hyali- pennis Meigen (1820), not Fabricius, concinna Costa (1883)]; harcyniae Loew (1844); humeralis Zeller (1840), Ayalipennis Fabricius (1794) [=anomala Mac- quart (1826), flavipes Meigen (1804), frontalis Meigen (1804), not Fabricius, varipes Meigen (1820) ] ; kowarzi Frivaldszky (1877); lata Loew (1853) ; lateralis Mei- gen (1804) [=haemorrhoidalis Meigen (1820), not Fabricius]; Jenta Becker (1923); linearis Fabricius (1787), [=linearis Meigen (1830) , cingulata Zetterstedt (1849) ]; liturata Loew (1873); longicornis Meigen (1820) [=frontalis Panzer (1797)]; lugens Loew (1873); meridionalis Bezzi (1898); meyert Nowicki (1867), meyer nigripes Engel (1930) ; minuta Pallas in Wiedemann (1818) [=maculata Wiedemann (1818) ]; mixta Becker (1923) ; navasi Séguy (1929) ; nigribarba Lowe (1871) ; notha Séguy (1941) ; ochrifacies Becker (1906); velandica Linné (1758) [=nigra Latreille (1804) ], oelandica limbata Loew (1840); podagrica
30 UNITED STATES NATIONAL MUSEUM BULLETIN 224
Schrank (1781); pollinosa Loew (1870); puerilis Becker (1923); rakanensis Matsumura (1916); rufa Strobl (1906) ; rufipes De Géer (1776) [=flavipes Fal- len (1814), frontalis Fabricius (1794), pratensis Olivier (1789), venosa Fourcroy (1785)]; ?rufipes Scopoli (1763) [=ruficornis Olivier (1789) ]; rujithorax Loew (1853) ; rwngst Timon-David (1951) ; samarana Becker (1923); segmentaria Becker (1923); speculifrons Wiedemann in Meigen (1820), speculifrons gagatoides Strobl (1906) ; strandi Duda (1940); swdentica Duda (1940); valida Loew (1856); wiedemanni Meigen (1820).
Ethiopian (allocation dubious) : Dioctria ?flavipen- nis Macquart (1838); morio Fabricius (1794); stig- maticans Fabricius (1805).
Australian (allocation dubious): Dioctria conopso- ides Fabricius (1775).
Locality unknown: Déioctria horsleyi Walker (1851).
Ricardo (1912), states that Dioctria horsleyi cannot be a Dioctria as the foretibia has a spine, but she makes no suggestion of where to place it. It is left here pending further study.
Immature stages of European species of Dioctria are well known and at least 5 species have been dealt with by Beling (1882), Brauer (1883), Lundbeck (1908), de Meijere (1916), and Melin (1923).
The species of the three subgenera proposed for Nearctic species by Wilcox and Martin have been in- cluded under Dioctria. The relation of Palaearctic species to these subgenera is unknown.
Subgenus Eudioctria Wiicox and Martin
Eudioctria Wileox and Martin, Ent. Americana, vol. 21, p. 8, 1941. Type of subgenus: Dioctria albius Walker, 1849, by original designation.
Distinguished by the flat and bare scutellum and stout microtuberculate bristles on the ventral surface of the hind femur and tibia. Species tend to be dimor- phic. Found in the eastern and Pacific Coast states but not thus far in the middle western states. Eleven species included.
Subgenus Metadioctria Wilcox and Martin
Metadioctria Wilcox and Martin, Ent. Americana, vol. 21, p. 19, 1941. Type of subgenus: Dioctria rubida Coquillett, 1893, by original designation.
Characterized by the long, erect hairs along the scutellar margin; scutellum flattened; femur and tibia lack setigerous bristles. Hind tibia and metatarsus normal, the latter subequal to the length of segments two and three combined. Two species included.
Subgenus Nannodioctria Wilcox and Martin
Neodioctria Wilcox and Martin, Ent. Americana, vol. 21, p. 7, 1941. Type of subgenus: Neodioctria albicornis Wilcox and Martin, 1941, by original designation. Preoccupied by Asilidae Ricardo, 1918.
Nannodioctria Wilcox and Martin, Bull Brooklyn Ent. Soc., vol. 37, p. 35, 1942. Change of name.
First and second antennal segments nearly equal in length, the third narrow basally and quite broad in
PART 1
the middle, its microsegment minute; face profile slightly convex, the epistomal area and antennal base not prominent. One species known.
Genus Echthodopa Loew Ficures 1, 404, 803, 812
Echthodopa Loew, Berliner Ent. Zeitschr., vol. 10, p. 16, 1866. Type of genus Echthodopa pubera Loew, 1866, by monotypy.
Echthopoda Loew, Beschreibungen europiiischen Dipteren, vol. 2, p. 78, 1871. Author’s emendation.
Flies of medium size. Distinguished from Dioctria Meigen chiefly by the numerous, strong bristles on the anterior surface of the middle femur and the lateral surface of the hind femur, together with the dense tuft of bristles or bristly hairs on the lower end and ele- vated third of the face. The hind femur and middle femur are rather stout; the pile of the legs is dense and fine; the mesonotal bristles are weakly differen- tiated and the occiput, pronotum and scutellum bear only stiff hairs. Palpus with a distinct vestige of the antepenultimate segment. Length 12 to 16 min.
Head, lateral aspect: The head is of medium length with the face short and gently elevated on the lower third. The occiput is scarcely visible on the upper portion, due to the posterior encroachment of the eye, but is prominent below on account of the anterior recession of the eye. Occipital pile abundant, long and rather fine, the dorsal elements proclinate, and coarse. Bristles absent. Proboscis of moderate length and longer than the face, stout basally with well developed medial dorsal ridge, the apex bluntly pointed, its halves slightly divergent and the basal half with numerous, long, fine hairs ventrally. Palpus with the ultimate segment spindlelike, not porate, carrying bristly hairs on all sides and attached to one side of the apex of the penultimate segment. This penultimate segment, which is bowl-shaped, is separated by a distinct basal constriction from a rounded, dorsally fused, antepen- ultimate segment. Basal segments of palpus with long, abundant pile. Antenna attached at the upper fourth of the head, elongate and slender, the first two seg- ments of nearly equal length, the third segment a little longer than the combined length of the first two and bearing two stout microsegments. The distal micro- segment is the longer, is spoon-shaped and bears a dor- sally exposed spine. The medioventral surface of the third segment has an oval patch of modified pubescence similar to that found in Dioctria.
Head, anterior aspect: Face densely pubescent, pile concentrated on the lower elevated portion and con- sisting of a dense, broad patch of long, slender bristles or bristly hairs. Subepistomal area large, pubescent, with medial depression. The face below antenna is moderately wide and slightly divergent below. Front sunken, not pubescent, with stiff, long hairs laterally. Vertex moderately excavated, the ocellar protuberance prominent, with vertical sides. Anterior ocellus en-
DASYPOGONINAB
larged and only stiff, ocellar pile present. The an- terior eye facets slightly enlarged.
Thorax: The thorax shining, without pollen, except on the postcallus and immediately before the scutellum and on the upper half of the pleuron, where only iso- lated patches of pollen occur, the largest being on the upper half of the mesopleuron, and with a more or less continuous, narrow, oblique band of pollen from the anterior sternopleuron to the posterior hypopleu- ron. Mesonotum of moderate height, with dense, suberect pile and poorly differentiated bristles. The following complement of bristles present: 5 notopleural, 6 to 8 supraalar, 5 postcallar, no scutellar, and 4 or 5 quite weak postdorsocentral bristles. Scutellum con- vex, with long pile and stiff, marginal hairs. The pro- pleuron and the pronotal collar bear dense, long, stiff hairs, without bristles. Mesopleuron, the anterior and upper posterior sternopleuron and the posterior hypo- pleuron with abundant, long, stiff pile. Metapleuron swollen, with long pile and 5 or 6 quite long, weak, bristly hairs. Metanotal callosity pollinose only. Basalare pubescent only. Tegula with short bristles. Slopes of metasternum pilose. Postmetacoxal area membranous.
Legs: Hind femur distinctly stout and narrowed only at the immediate base. Pile of femur on all sides dense, fine, long and erect; the ventral fringe is conspicuous, the lateral surface with 12 to 18 stout microtubercu- late bristles, the dorsal half of the apex with a circlet of 8 bristles. The hind tibia bears 6 dorsal and 6 dor- solateral bristles and 5 stouter, ventrolateral bristles; the apex bears 15 bristles, most of them ventral; me- dial and ventral surfaces with dense appressed setae on the apical half. Anterior and midfemur both stout with long, fine pile. Bristles are confined to the anterior surface and outer portion of the middle femur, which area bears 12 stout bristles. Bristles on the an- terior and middle tibia confined to a double dorsal row containing approximately 8 elements. Tarsal seg- ments rather short, the basitarsus about twice as long as each succeeding segment. Claws sharp, strongly curved at the apex, pulvillus well developed. Empo- dium swollen at the base, reduced in length.
Wings: Marginal, all posterior cells and the anal cell widely open. Fourth posterior cell slightly narrowed, the third correspondingly widened. Small crossvein at the middle of the discal cell. Alula well developed ; ambient vein complete. Wings without pattern, nearly hyaline.
Abdomen: Cylindroid, less wide than the mesonotum, 7 tergites present in the male, with a linear trace of the eighth; 8 are present in the female, the seventh not quite half as long as the sixth. Pile of abdo- men abundant, stiff, more or less appressed; the side of the first tergite bears numerous quite weak bristles. Male terminalia large, conspicuous, not rotate. Epan- drium quite large, convex, laterally extensive, fully cleft to the base, with proctiger small and recessed. Hypandrium forms a large broad curled protuberance turned slightly upward and enclosing the interior
535914—62—pt. 14
ROBBER FLIES OF THE WORLD 31
structures. The gonopod is largely enclosed by the epandrium. Female terminalia recessed, inconspic- uous, without spines; its ventral plate is short and me- dially notched.
Immature stages unknown. The adults frequent low growing foliage at the edge of woodlands.
Distribution: Nearctic: Lehthodopa carolinensis Bromley (1951) ; formosa Loew (1872) ; pubera Loew (1866).
Genus Dicolonus Loew Ficures 3, 406, 804, 813, 1658, 1803, 1879, 1960
Dicolonus Loew, Berliner Ent. Zeitschr., vol. 10, p. 32, 1866. Type of genus: Dicolonus simpiex Loew, 1866, by monotypy.
Small or medium size flies. Related to Déoctria Meigen and characterized by the short, dense, brushlike pile, the elongate, slender antenna, with its spoon- shaped microsegment, the short, robust tarsal segments, the absence of bristles, the dense mystax on a rounded, ventral, facial protuberance, and the short, blunt pro- boscis. From all other genera in the lower Dasypo- goninae, it is separated by the hairy metanotal callos- ity. Female terminalia without spines. Length 10 to 15 mm.
Head, lateral aspect: Length greater than usual, with tumid occiput and moderately long face. The face is prominent on the upper portion and still more on the lower half where it extends as a conspicuous, rounded elevation. Middle of face not quite plane with the eye margin. The occiput is especially prom- inent below due to the anterior recession of the eye and the lower angle of the eye is comparatively sharp. Above, the occiput continues to be swollen but in pro- file is obliterated before reaching the vertex; its pile dense, coarse and long; bristles absent. The proboscis is exceptionally short, robust and blunt, the halves of the apex slightly divergent. More than half the ven- tral surface with numerous, long, fine hairs. The pro- boscis is directed forward, the apex blunt. Palpus clearly with a vestige of the antepenultimate segment, demarcated from the following segment; end segment not porate, robust, clavate with stout apical, lateral apical and medial bristles. Antenna longer than the head, slender, the first segment two or more times as long as the second, third a little longer than the com- bined length of the first two. The third segment bears a single elongate, oval, spoon-shaped microsegment car- rying an enclosed spine. There is some trace of a shorter, second, but fused, microsegment lying between the third segment and its spoon-shaped apical segment. Like Dioctria the third antennal segment has an elongate ventral patch of differentiated pubescence.
Head, anterior aspect: Face for the most part pubes- cent but with some nearly bare areas, one of them located beneath the antenna. The prominent and swol- len upper portion of the face has a tuft of dense, long, fine pile and the lower elevated portion of the face has still longer, more dense, slender bristles or bristly pile. Subepistomal area prominent, sloping, not excavated,
32 UNITED STATES NATIONAL MUSEUM BULLETIN 224.
bare and with medial carina. Front short, due to the position of the antenna attached at the upper seventh of the head. Front nonpubescent with long bristly hairs laterally, the vertex is scarcely excavated, the ocellar protuberance quite low with vertical sides and all the ocelli enlarged. Between the ocelli there are long stiff hairs.
Thorax: Mesonotum comparatively low and uni- formly convex anteriorly and posteriorly, shining, without pubescence but with dense, coarse, rather long, subappressed pile. Bristles absent. Scutellum con- vex with long coarse erect, discal and marginal pile. Propleuron and collar densely long pilose, without bristles. _Mesopleuron with long pile dorsally and similar but less abundant pile present on the posterior hypopleuron, anterior and posterior sternopleuron. The swollen metapleuron with abundant pile and a number of long bristly hairs. Much of the pleuron is polished and bare, its pubescence chiefly restricted to the metapleuron and posterior hypopleuron with small patches elsewhere. Metanotal callosity with a patch of coarse pile in addition to pubescence. Squa- mae with a long fringe, slopes of the metasternum pilose, postmetacoxal area membranous.
Legs: All the femora moderately stout, especially the middle and hind pairs and densely covered with long, fine pile on all surfaces. Bristles absent. On the tibiae there are on all surfaces rows of quite long, very slender, bristly hairs. On the tarsi there are some dis- tinct though slender bristles which become stouter on the lateral and medial margins. Claws sharp, curved from the base; pulvillus well developed. Empodium reduced and strongly swollen at the base. The tarsal segments are unusually short, the three intermediate segments monilliform, the basal segments not quite as long as the two succeeding segments.
Wings: Marginal, all the posterior cells and the anal cell widely open. Fourth posterior cell slightly nar- rowed, the middle end vein of the second basal cell pres- ent. Alula short. Ambient vein complete.
Abdomen: Broad, nearly or quite as wide as the thorax in the females. Slightly less wide in the males. Seven tergites present in the male with a linear trace of the eighth. In the female eight tergites present, with the seventh half as long as the sixth. Abdominal pile abundant, coarse, erect and brushlike laterally, appressed dorsally. Male terminalia not or only slightly rotate to the left. The epandrium wide, thin, uncleft and at most very shallowly excavated, and bear- ing long, flat, apically rounded, sharp-edged, lateral protuberances. Gonopod largely concealed but with two prominent, acutely pointed, narrow protuberances. Hypandrium short, narrow, broad at base. Female terminalia short, without terminal spines, the basal plate laterally with a stout, blunt, downward turned protuberance. ‘There is considerable similarity of both the male and female terminalia to those of A/yelaphus Bigot.
Distribution: Nearctic. Décolonus (1866) ; sparsipiloswm Back (1909).
simplex Loew
PART 1
Palaearctic. Dicolonus Matsumura
(1916).
argentatus
Genus Myelaphus Bigot FIGURES 294, 298, 398, 844, 853, 1677, 1887, 1948
Myelaphus Bigot, Bull. Soc. Ent. France, ser. 6, vol. 2, p. xci, 1882. Type of genus: Myelaphus melas Bigot, 1882, by monotypy.
Myielaphus Kertész, Catalogus dipterorum . . 1909. Emendation.
. vol. 4, p. 96,
Peculiar flies, characterized by the subglobular head, the dorsal protuberance of the face and front on which the extremely long antenna is set. The third antennal segment bears 2 peculiar microsegments, the first short but with 2 divergent, apical, lappetlike extensions, the third longer and attached between these lappets. Mesonotum rather humpbacked and convex, densely ap- pressed pilose and without lateral bristles except for 2 weak, rather short, notopleural bristles. The head is set rather low on the thorax and the abdomen is droop- ing and these features tend to emphasize the hump-’ backed appearance. Length including antenna 12 to 14 mm.
Head, lateral aspect: The face is rather prominent, especially on the upper half; this extension involves the front also and constitutes a rounded, domelike pro- tuberance bearing the antennae; these structures are directed strongly upward. The face just below the middle has a rounded, protuberant, transverse exten- sion leaving the intervening area concave and the low- ermost face strongly receding. The eye is unusually long, a little more narrow above and quite convex ante- riorly ; it is nearly plane on the upper half of the poste- rior profile, the lower half strongly convex due to a gradual anteroventral recession. The occiput is excep- tionally thick in the middle and ventrally, and particu- larly toward the medial portion; it slopes rather grad- ually down to the eyes and is receding and obliterated dorsally. Pile of occiput moderately abundant, coarse and almost bristly in the middle though rather fine, scanty and not very long ventrally. Dorsally are a few, slender, proclinate, bristly hairs. The proboscis is swollen towards the base both in lateral and dorsal as- pect; it is subeylindrical distally with a bluntly rounded apex; it carries a number of short, stiff hairs placed apically and in a ventrolateral row which extends over the entire outer third of its length. The subbasal ventral portion bears numerous fine, long hairs; dorso- medial ridge absent. The proboscis is directed hori- zontally forward and extends a short distance beyond the face. Palpus of 2 segments, the first seement exca- vated, the second not porate and set at a slight angle, short, more slender with apical bristles and with some stiff, dorsal lateral and medial hairs.
The antenna is attached on the swollen and rather protuberant upper face and front almost on a plane with the vertex; it is attached about one-fifth way down below the upper eye margin. The antenna is extraordinarily long and peculiar. The first segment
DASYPOGONINAB
is two to three times as long as the second segment. The third segment is more than twice the combined length of the first 2 segments and consists of a long, slender structure which is a little compressed laterally and with an annular base and is divided into 3 parts or subsegments. The third segment, without microseg- ment, is as long as the 2 terminal subsegments or may be longer. Each microsegment is inserted between a pair of winglike, lateral processes extending from the apex of the preceding section or portion of the third seg- ment. Apex of each subsegment with coarse, dense, short pubescence.
Head, anterior aspect: The face is wide, slightly wider below, more or less shining with both transverse and longitudinal wrinkles, or fine impressed lines. There is very little micropubescence and such as is present is confined to the eye margin and lower face. Pile absent. Bristles restricted to 2 or 3 closely adja- cent rows of moderately long, stout, pale, thickset ele- ments situated transversely immediately above the epistoma. Subepistoma large, slightly oblique, con- cave. Cheeks short. The front is prominent, pol- ished, largely bare with a tuft of short, stiff hairs in front of each antenna. Anterior half of front swollen and protuberant. Eye margin with 7 anteriorly directed, somewhat appressed bristles, 4 of which are quite stout. The vertex is slightly narrowed but not conspicuously. Ocellarium large, wide and of mod- erate height with large ocelli and a row of 3 or 4 short bristles or bristly hairs on each side between the ocelli.
Thorax: The thorax is prominent and moderately arched, uniformly from front to rear and rather densely beset with flat appressed, short, sharp, undif- ferentiated setae, each with a microtubercle at the base. There are no bristles anywhere on the thorax. A few erect hairs are present on the postalar callosity, some sparse, appressed setae on the mesopleuron, sterno- pleuron, hypopleuron and the pronotum and meta- pleuron with a few fine, long hairs more numerous on the former. Scutellum thick and obtusely convex with scattered, appressed setae. Prosternum fully dissoci- ated. Postmetacoxal area membranous, lateral meta- sternum with long, fine hairs.
Legs: All the femora are stout, the hind pair a little swollen gradually on the distal half. Thefirst 4 femora are a little swollen on the basal half and quite stout distally. All the legs have rather abundant, fine, appressed setae throughout. Hind femur on the basal third with a doubled and partly trebled row of quite short but very stout, spinous bristles or short spines; there may be at least 20 such. Hind tibia with very short, scanty, spinous bristles situated chiefly distally but with a few on the basal half; there are 4 dorsolat- erally and 4 to 6 ventral elements. The hind tibia are stout throughout but also gradually become widened distally. The basitarsus is unusually robust and rather short, yet is nearly as long as the next 8 seg- ments, which are quite stout and short. Apex of hind tibia with 14 short bristles, almost all of them on the ventral half. Middle femur with 8 to 10 moderately
ROBBER FLIES OF THE WORLD 33
long, stout, posteroventral bristles on the basal half, a few short ventral bristles distally and with a charac- teristic cluster of rather dense, curved, sharp spines or spinous bristles anteriorly near the base. Those of the cluster which are more distal are shorter in length. Middle tibia with a ventral row of 5 exceptionally slender bristles or bristly hairs and 6 or 7 short, pos- terior bristles, a like number of still shorter postero- dorsal bristles.
Anterior femur with 7 or 8 moderately long, coarse, ventral bristles on the basal half; its tibia is rather similar to the middle tibia and without spine at apex. Anterior basitarsus, like all the other basitarsi, is quite short and robust and equals the combined length of the next 2 segments. Claws stout, sharp, bent only at apex; pulvillus large, broad; the empodium sharp, bladelike, strongly swollen at the base.
Wings: The wings are generally strongly tinged with brown or bluish black. Marginal cell widely open; the second submarginal cell is rather wide at base but arises as an arch and often has a spur vein extended towards the base. The anterior branch of the third vein curves forward to end just above the wing apex; the posterior branch ends a considerable distance behind the apex and the first posterior cell is narrowed but open. Third posterior cell either narrowly open or closed with a short stalk. Anal cell closed and stalked. Posterior cross vein present, the nearly rectangular anterior cross- vein enters the discal cell at or just beyond the middle. All the veins are exceptionally stout; the ambient vein is complete; alula well developed but hemicircular; en- tire wing villose.
Abdomen : The first segment is a little wider and com- paratively short. It is nearly or possibly equally wide as the mesonotum. Sides of abdomen parallel through most of its length or nearly, therefore the abdomen is comparatively broad and robust. It is shining, with scanty, fine appressed, setate pile, a little more abundant on the terminal segment. Sides of first segment with 2 or 3 pairs of slender bristles and a little long, coarse hair. Males with 8 segments but the eighth segment reduced to a short, dorsal, liplike protrusion from be- neath the quite short seventh tergite. Females with 8 tergites, but the last two are short. Male terminalia moderately large and obtuse. The epandrium has a deep, almost circular sulcus which encloses the short, protruding proctiger and then turns downward and also inward toward the median line; the two portions do not meet. The posterior portion of the epandrium, there- fore, is obtuse and downturned and reminds one of Heteropogon Loew. Hypandrium extremely short and almost concealed. Gonopod large, swollen, and widened towards the base, with a slender, terminal, hooked process and with a much longer, straight, pronglike dorsal process. Female with the terminalia very short, recessed within the posterior cavity, without spines. Eighth sternite with a prominent, thin, gently rounded, lateral, flaplike extension; and lying between these lateral flaps is a more narrow, pointed, sharp, pilose, submedial process divided posteriorly by a cleft.
34 UNITED STATES NATIONAL
Distribution: Nearctic: I/yelaphus lobicornis Osten Sacken (1877); melas Bigot (1882); rufus Williston (1884).
Palaearctic. Myelaphus dispar Loew (1873); jo- zanus Matsumura (1916).
Hermannella, new genus Ficurss 11, 421, 845, 854
Type of genus: Hermannella engeli, new species.
A rather small fly characterized by the unusually long head and the long, greatly flattened antenna carrying two wide, flattened microsegments. It appears to be related to Scylaticus Loew. It is distinguished from Scylaticus by the very short proboscis and unusual an- tenna; and from Myelaphus Bigot by the greatly wid- ened vertex, as well as the not cleft microsegments. Length 12 mm. including antenna.
Head, lateral aspect: The head is unusually long and subglobular. The face rather long throughout its length, not quite straight in profile, but rather strongly retreating below the antenna. The eye is exceptionally long and strongly convex posteriorly as well as an- teriorly. Occiput unusually tumid and thick through- out, following the eye in its curvature and with a slight thickening or bulge at the margin of the eye. Pile of occiput stiff, short and scanty through the middle, some- what longer above and absent ventrally; all this pile partakes of the character of weak bristles. Proboscis exceptionally short, not or scarcely projecting beyond the face. It is dorsoventrally compressed but with bluntly rounded apex, and bears no ventral basal pile and only 2 or 3 fine hairs ventrally near the middle. Palpus short, cylindrical, with some apical bristly hair and the second segment more slender, distinctly attenu- ate, and apparently without pile or bristles. A small apical pore appears to be present. The basal segment is hemicylindrical and excavated at least on its basal half. Antenna attached at the upper sixth of the head and unusually elongate. The first segment is 314 times as long as the short beadlike second segment and is some- what swollen below and subapically. The third seg- ment is subquadrate basally with sharply angular margin dorsally and becomes quite strongly compressed laterally especially along the dorsal margin. The ven- tral margin remains a little wider. The third segment is gently widened on the apical half, somewhat curved upward and laterally. If the apical subsegments are excluded, then the third segment is 214 times as long as the first segment. The third segment bears two com- pressed subsegments, each of about equal length and height. The second subsegment has a lateral apical notch and between the ventral and lower portion of this notch there is a minute spine. First antennal segment with numerous, long stiff hairs ventrally, shorter ones laterally and dorsally, the second segment with a few minute lateral and dorsal setae.
Head, anterior aspect: The face below the antenna is a little less than one-third the head width; it has
MUSEUM BULLETIN 224 PART 1 parallel sides. The front is quite strongly divergent, the width at vertex more than two-thirds the head width. Subepistomal area small, horizontal, concave. Face micropubescent, everywhere covered, except at the immediate eye margin, with moderately long, stiff pile; bristles absent. Front extremely wide but short; on the lateral third there is a conspicuous tuft of moder- ately long bristly hairs. The vertex is not excavated, the ocellarium large, wide, moderately high and bear- ing three or four pairs of slender bristles across the middle. Anterior eye facets slightly enlarged.
Thorax: The thorax is pollinose, the mesonotum of moderate height. Pile of mesonotum abundant, fine and erect and continuous across the mesonotum. Acrosticals are not or very poorly differentiated, dorsocentral bristles absent; humerus with stiff pile. The lateral mesonotum has the following complement of short, weak, slender bristles: 2 notopleural, 2 supra- alar, 2 postalar; the strongly flattened scutellum with 6 pairs of comparatively short, stiff hairs; the somewhat wrinkled scutellar disc is without pile. The pro- pleuron has only scanty, stiff hairs ventrally and weak bristly hairs posterolaterally; the anterior collar has 4 or 5 pairs of moderately stout bristles; the sterno- pleuron, pteropleuron and hypopleuron apilose; meta- pleuron with a vertical row of 5 or 6 short bristles. The metanotal slopes are micropubescent only; lateral metasternum long pilose, the ventral metasternum without pile, the postmetacoxal area membranous; basalare with fine long hairs.
Legs: The legs are densely, coarsely appressed setate, dorsally and laterally on the femora. AI] the femora are stout without being thickened. On the hind femur is the following complement of bristles: 5 or 6 weak slender lateral, 7 or 8 weak ventrolateral, and some short weak ventromedial; the hind tibia has 8 short, weak dorsal bristles, 5 similar lateral, and 3 to 5 similar ventrolateral. The middle femur has 8 slender bristles posteroapically, its tibia has 5 or 6 slender bristly hairs dorsally and 7 or 8 equally slender but longer elements posteriorly, besides 3 or 4 short bristly hairs antero- ventrally. Anterior tibia similar to the middle tibia; the dorsal and posteroventral bristles as weak or more weakly developed and lacking an apical spine; the anterior femora with only short stiff pile. Anterior basitarsus fully as long as the next 3 segments; claws sharp; the pulvillus well developed; the empodium long and slender.
Wings: Marginal cell widely open, the anterior branch of the third vein is sinuous or sigmoid, ending just before the wing apex. First and second posterior cells widely open, fourth open but strongly narrowed, anal cel] closed with a short stalk; the alula short and hemicircular in outline; ambient vein complete.
Abdomen: The abdomen is comparatively robust, not quite as wide as the mesonotum and slightly narrowed at the end of the second tergite. There are 7 tergites in the male, the seventh is two-thirds as long as the sixth. Pile of the abdomen rather scanty, subap- pressed and setate but long and abundant on the sides of
DASYPOGONINAB
the first and second and to a lesser extent on the third tergite. Male terminalia rather short, rotate one-half, the hypandrium short.
I have seen only a male, and have placed the species in the Dioctrini provisionally. Should the females prove to have spiny acanthophorites, this genus will fall within the Dasypogonini.
Distribution: Ethiopian: Hermannella engeli, new species. From Rhodesia,
Hermannella engeli, new species
Rather small, dark reddish brown flies with very short pile. Readily recognized by the peculiar an- tenna. The first antennal segment is more than three times the length of the minute, second segment. The third segment, with microsegments excluded, is about 214 times the length of the first segment and it bears 2 wide, conspicuous microsegments flattened and each of about equal length and breadth. Pile of head and thorax pale. Length 12 mm. including antenna.
Type. Male, Rhodesia. In the collections of the British Museum (Natural History). This individual bore the name Myielaphus pardalinus Engel, which is apparently a manuscript name as I can find no evidence that it has been published. I take pleasure in naming the species in honor of Dr. Engel and of the monu- mental and valuable studies of Palaearctic and Ethio- pian Diptera which he completed.
Genus Nerterhaptomenus Hardy Ficures 2518a-£, 2521
Nerterhaptomenus Uardy, Proc. Linnean Soc. New South Wales, vol. 54, p. 359, 1929. Type of genus: Nerterhapto- menus morus, 1929, by Monotypy.
I was unable to see the type, and, therefore, quote the original description :
A brownish species with the head, pronotum, pleura, coxae, and venter coloured ashy grey. The antennae have five clearly defined segments, the third long, the fourth shorter than the fifth, at the apex of which is a small spine. The face has rather scanty white bristles forming a moustache, but it is without an apparent tubercle. The bristles on the frons and antennae are mostly black; those elsewhere and the hairs are white, includ- ing the postoculars and the beard.
The thorax has a black area near the head, and this continues as two black median stripes that do not extend beyond the transverse suture; on each side of this marking is a large black spot. The bristles of the thorax are weak, but the two white presutural, one supra-alar, and one post-alar are detected on each side. The dorsocentrals are not to be detected and the scutellum is bare. The metapleural bristles are well developed, but the hypopleurals are absent. The metanotum is bare and the metasternum is narrowly separated from the intermediate coxae. The prosternum is contiguous with the pronotum, being separated by a groove. The rather typical shaped plate adjacent to the anterior coxae can be traced in part, but contains a bridge comparable to that found in the Ommatiini.
The second segment of the abdomen is short and about the same length as the third. The sixth, seventh, and eighth seg- ments are black and strongly depressed in the female, and are of equal length. On the male the abdomen is somewhat club- shaped, as it swells out between the fifth and seventh segments.
ROBBER FLIES OF THE WORLD 35
The ninth tergite is emarginate at the apex and the upper lamella is divided, making three lamellae. The claspers are hinged and the aedeagus is short as if stunted.
The brown legs are more or less stained with black in parts, and there is no spur on the anterior tibiae. The hind metatar- sus is strongly swollen. The bristles are poorly developed on the femora and show no marked characters. The wings have a simple venation, with the cubital and anal veins coalescing close to the wing margin, and the radio-median cross-vein is situated well before the middle of the median cell. Length 13 mm.
Distribution: Australian: Verterhaptomenus morus (1929), Brisbane, Queensland.
The long, drawn-out ovipositor of the female is of a generalized type. All aspects considered, the rela- tionship of this fly appears to be with the Dioctrini.
Genus Pritchardia Stuardo Ficures 22, 45, 422, 809, 818, 1020, 1029, 1659, 1884, 1909, 2002
Pritchardia Stuardo, Catalogo de los dipteros de Chile, p. 80, 1946. Type of genus: Dasypogon hirtipes Macquart, 1838, by original designation.
Strobilopygius Hull, Bull. Brooklyn Ent. Soc., vol. 51, p. 70, 1956. Type of genus: Dasypogon hirtipes Macquart, 1938, by original designation.
Flies of medium size or smaller, of dark coloration and sparsely pilose. The lower two-thirds of the face is strongly protuberant, with many long bristles. The legs are stout and bristly. The abdomen is tapered, but rather wide at the base and distinctly flattened ; the fourth posterior cell is closed. These flies suggest Hypenetes Loew in appearance, differing sharply in the not attenuate, third antennal segment and the absence of spines on the female terminalia. Length 12 mm.
Head, lateral aspect: The face is strongly convex and protuberant, but the protuberance is restricted to the lower two-thirds, leaving the upper third barely visible in profile. The occipital bristles are weak in the mid- dle, becoming stronger near the vertex, where they are strongly proclinate. Proboscis short, stout, held almost horizontally, slightly compressed laterally. Palpus clearly of two segments; first segment hemi- cylindrical and excavated; second segment porate, with numerous, fine, long hairs. The antenna is short, the first segment nearly twice as long as the second and both with abundant, rather long pile dorsally, laterally and ventrally. Third segment strongly swollen dor- soventrally, laterally compressed, and narrowed only at base and apex.
Head, anterior aspect: The face has numerous, ex- tremely long, stout bristles directed for the most part forward but slightly downward, the upper bristles more or less curved, the greater portion of these bristles spread out as a triangular patch on the anteromedial part of the protuberance. Long bristles are also pres- ent on the lateral margin of the subepistomal area. The front is strongly divergent in the middle, but slightly narrowed at the vertex; it bears numerous, fine, long, erect hairs, which are especially long and stout at the vertex. The ocellar protuberance is low,
36 UNITED STATES NATIONAL MUSEUM BULLETIN 224
with oblique sides, ocelli set at vertex. Ocellar bris- tles consist of 3 or 4 pairs of moderately long, stiff, slender bristles.
Thorax: The thorax is pollinose and generally dull; the pile is scanty, fine and erect, becoming much longer in front of the scutellum, where there is an irregular double row of hairs on each side. Acrostical and dorsocentral bristles present anteriorly. Humerus with numerous, fine, long hairs. The mesonotum shows a tendency to a moderate complement of long bristles of moderate thickness and which become fine apically. Material studied shows the following complement of bristles: No humeral or posthumeral bristles, 2 noto- pleural, 2 supraalar, 3 postalar, and 4 pairs of scutellar marginal bristles. The scutellar surface is quite flat, with 12 fine, erect hairs confined to the sides; surface densely pollinose; margin without bristles or hairs. Pleuron pollinose, with pile absent on the hypopleuron ; lower propleuron and upper propleuron with numerous, long, fine hairs and no bristles; anterior pronotal collar with numerous, fine hairs and a few weak bristles. Poststernopleuron with 8 to 10 long hairs. Mesopleu- ral junction with a tuft of short pile.
Legs: All femora stout, especially the anterior and middle pair. Hind femur slightly attenuate basally; tibia not greatly thickened. The hind femur bears stout, moderately long bristles: 1 dorsal near apex, 2 dorsolaterals in a row shortly removed from apex, and 8 laterals situated over the middle area. The hind tibia is densely appressed pilose with a few long, scat- tered bristly hairs ventrally and laterally and medi- ally near the base, and bears stout, curved moder- ately long bristles as follows: 3 dorsomedial, 3 dorso- lateral; 3 ventrolateral; the apex bears 2 medial, 1 dorsal, 3 laterals, and 2 long ventrals enclosing two short bristles. Hind metatarsus little more than half as long as the remaining segments. Midfemur short appressed pilose above, densely, long, bristly pilose below, with a stout, long bristle anteriorly just be- yond the middle and another posteriorly near the apex; its tibia has moderately long, basally stiff, fine, attenuate bristly pile situated posteriorly, anterodor- sally, and anteriorly, as well as ventrally. The middle tibia is densely appressed pilose with a few long, scat- stout bristles as follows: 2 anterior bristles from the middle and beyond, 2 anterodorsal, 2 posterodorsal, 1 posteroventral, and at the apex 1 anterior, 2 dorsal, 1 posterior, and 4 ventral bristles. Anterior femur with long, stiff, bristly pile dorsally, but confined to the posterior half and extending undiminished on the posterior and ventral surfaces. Its tibia is similarly covered with long bristly pile on the same area, and has 3 posterodorsal bristles. Apex of anterior tibia with- out spine, pulvillus well developed.
Wings: Marginal cell widely open. Anterior branch of the third vein ends before the wing tip, fourth pos- terior cell closed and stalked. The second basal cell is closed with 2 veins and a short stalk beyond. Anal
PART 1
cell closed and stalked. Alula moderately wide; am- bient vein complete.
Abdomen: The abdomen as long as the wings, gently tapered, distinctly flattened, the first tergite is later- ally swollen and convexly ridged and this segment is as wide as the mesonotum. Female with more strongly attenuate and pointed abdomen. Six tergites are well developed in the male, the seventh is visible dorsally but quite short, the eighth can also be seen from above but is a mere linear ridge. Seven tergites present in the female; the eighth forms part of the ovipositor. There are 2 or 3 weak bristles, or coarse bristly hairs, present in the posterior corners of ter- gites 2 to 6. Male terminalia conspicuous, epandrium cleft into superior forceps, which are well developed; terminalia not rotate. Female terminalia short, thrust obliquely upward, with the terminal portion held at right angles and without spines.
Distribution: Neotropical: Pritchardia hirtipes Mac- quart (1838) ; puella Bromley (1932). In the Chilean
area. Genus Aplestobroma Hull
Ficures 13, 405, 808, 817, 1651, 1905, 1906, 2036, 2243, 2246
Aplestobroma Hull, Psyche, vol. 64, no. 3, p. 93, 1957. Type of genus: Aplestobroma avida Hull, 1957, original designation.
Flies of medium size, characterized by the subcircu- lar head with very narrow face and the rather cylin- drical, narrow abdomen, and readily recognized in the males by the long, dorsally placed hypandrium, which curls down apically and posteriorly over the termi- nalia. Male terminalia fully rotate. In the females the terminalia are deeply recessed within the eighth tergite, which forms an overlapping hood. Spines of acanthophorites are absent. The anal cell is open; fourth posterior cell closed. Length 16 mm.
Head, lateral aspect: Face in profile scarcely visible on the upper three-fourths and only moderately pro- tuberant below and not produced beyond the general plane of the face. Eye unusually long and strongly convex anteriorly, slightly wider above, nearly plane over the middle portion of the occiput and not recessed below. Occipital pile present only below; it is mod- erately long and fine and abundant on the lower half of the head, replaced by numerous bristles above. The anterior row of bristles consists of 9 pairs and the bris- tles are exceptionally stout and very strongly procli- nate. Below and just above the middle of the head is a band of weaker bristles in 3 or 4 rows of 7 or 8 bristles each; these extend entirely around the upper portion of the occiput. Proboscis short but unusually stout, gradually swollen towards the base and bearing an exceptionally high medial ridge. The apex is dor- soventrally depressed and therefore in profile appears rather narrow and attenuate apically. It bears a num- ber of fine but stiff hairs along each ventrolateral mar- gin but only 3 or 4 hairs dorsally at the apex. Basal half of the ventral margin with some long, fine hairs.
DASYPOGONINAB
Palpus clearly of two segments; both segments small, short and robust, the first segment cylindrical and not excavated and not fused; the second segment bears a small apical pore. The first palpal segment bears long, fine pile ventrally; the second has stiff, bristly hairs ventrally, and laterally near the base, and sim- ilar hairs dorsally and subapically.
The antenna is attached at the upper fifth of the head; it is elongate, slender, slightly longer than the head. The first two segments are elongate and of nearly equal length. The third segment is slender, not quite as wide as the end of the second segment, with parallel sides to the middle and tapering gently to its ventrally oblique apex; it is slightly longer than the combined length of the first two and bears a stout, short, robust microsegment; its large, apical opening is dorsal, oblique and has a short spine. Pile of first segment restricted to the ventral and ventrolateral areas and consists of 10 to 12 stiff, oblique setae; apex with 2 or 3 quite long setae. Second segment with 5 setae above, the same number of longer, stouter setae below.
Head, anterior aspect: Face below antenna about one-ninth the head width. The face is slightly diver- gent on the upper half; at the bottom of the eyes the face is strongly divergent, its width one-third the head width. Subepistoma short. The face is pubescent and bears on each side submedially a single vertical row of 10 long, slender curled bristly hairs which begin at the base of the antenna. Lower middle of the face above the epistoma with a triangular area containing numer- ous, long, stout bristles directed obliquely downward; this group contains at least 25 elements. The front is quite narrow, slightly wider than the face below an- tenna; it has parallel sides continued to the vertex. Sides of front with four slender bristles; the vertex is scarcely excavated, the ocellarium moderate in height, rising above the eye margin and bearing 5 or 6 pairs of slender, moderately long, anteriorly directed bristles. Eye facets slightly enlarged.
Thorax: Mesonotum of moderate height, with dense velvetlike pubescence on each outer third, the medial portion of the mesonotum nonpollinose. Pleuron densely micropubescent, the mesopleuron chiefly bare. Pile of mesonotum scanty and fine, consisting of long, erect, subappressed setae. It bears a single row of acros- tical bristles, an irregular double row of dorsolateral bristles which vary in length from short to very long and which, opposite the wing, become quite long, com- prising 6 to 8 long bristles extending to the scutellum. Humerus with weak bristles; the margin from the hu- merus to the suture with numerous stout bristles and bristly hairs. The notopleuron bears 2 or 3 stout bristles in front. Supraalar has from 2 to 4 stout and 4 weak bristles. Postalar has 1 or 2 long and stout and several weak bristles. Scutellar margin with a single pair of stout bristles or 2 to 8 pairs of slender, weak bristles or bristly hairs. Propleuron with abundant, long, fine pile, the collar with 3 or 4 pairs of weak bristles and stiff pile. Mesopleuron apilose or with 8 or 9 long slender bristly hairs. Metapleuron with a vertical row
ROBBER FLIES OF THE WORLD 37
of 7 or 8 long slender bristles and additional pile before and behind. Metanotal callosity micropubescent only. Metasternal slopes with numerous long hairs, the meta- sternum densely long pilose, the postmetacoxal area membranous. The metasternum is narrow but rolled out and forward into a low transverse convex ridge.
Legs: All the femora and tibiae slightly elongate and comparatively slender, the hind pair especially so. The hind femur is slightly and gradually thickened towards the apex; its tibia thickened near the apex. The hind femur bears scattered, appressed setae dorsally, except near the base, and these continue down the upper half of the lateral surface; stout, sharp bristles are present as follows: 2 dorsomedial at the apex, 1 dorsolaterally at the apex, a single stout, medial bristle at the apical seventh, laterally a row of 4 stout bristles, row may con- tain as many as 9 bristles; ventrally on the basal half are 3 long, slender, attenuate bristles with a scanty row of fine, erect pile. The hind tibia bears 3 to 5 stout, long, dorsal bristles, 2 or 3 dorsolateral and 3 or 4 ventrolat- eral; apex with 12 bristles. The middle femur bears 1 to 3 dorsolateral apical bristles, 3 to 5 stout, anterior and only a fringe of long, fine pile ventrally. Its tibia has 5 weak dorsal, but of its 5 anterodorsal bristles, at least 3 are long and strong; it bears 4 to 6 long, strong posterior, and 2 to 3 long, strong, oblique, ventral bristles. Anterior femur with 2 weak dorsoapical bristles and 1 to 3 stout, anterior apical bristles; its tibia has a double dorsal row of short, stout bristles each con- taining 3 to 6 bristles and posterior row with 4 or 5 long, stout bristles. Apex of anterior tibia without trace of spine. Tarsus ends in slender, long, spatulate pulvillus; claws long and sharp.
Wings: The marginal cell widely open; the anterior
ranch of the third vein ends at or barely above the wing apex; the posterior branch ends well behind the apex; base of second submarginal cell arched forward. First posterior cell fully open; both end veins of the discal cell of approximately equal length; the fourth posterior cell closed with a long stalk. Anal cell widely open ; ambient vein complete.
Abdomen: The abdomen is comparatively slender and subcylindrical, slightly shorter than the wings. Sides of the first tergite swollen laterally; 7 well de- veloped tergites present in the male, the eighth appear- ing as a narrow, short, flap in the middle and right side only, or this segment completely concealed. Eight ter- gites present in the female, the eighth nearly as long as the seventh. Pile of abdomen short, appressed and setate in the middle of the tergites and becoming long and fine narrowly along the lateral margins. Sides of first tergite with 5 or 6 long, slender bristles, absent on the remainder of the abdomen. Sternites with long, slender, erect, bristly hairs. Male terminalia in the type of genus is fully rotate, the hypandrium forms a curled process, short on some species, in others greatly elongate and curled downward apically over the re- mainder of the terminalia. The epandrium is fully cleft, and developed into superior forceps, which are robust, convex and conspicuous and each with a long,
38 UNITED STATES NATIONAL MUSEUM BULLETIN 224
terminal process. Gonopod smaller but prominent. Aedeagus tubular at apex. All three divisions of the terminalia tend to be divergent dorsoventrally, leaving clefts between them. Female terminalia deeply recessed within the overhanging, hoodlike or shieldlike eighth tergite; the only structure, which can be discerned within this cavity is the spatulate, pilose, apical proc- tiger. After examining many females, I can find no evidence of acanthophorites or spines.
Distribution: Australian: Aplestobroma avida Hull (1957).
Genus Broticosia Hull Ficures 12, 408, 841, 850, 1653, 2244, 2247
Broticosia Hull, Psyche, vol. 64, no. 3, p. 91, 1957. Type of genus: Broticosia rapax Hull, 1957, by original designation.
Rather smaller than medium size and slender flies with long, somewhat compressed abdomen. They are immediately recognized by the circular head, the ex- tremely narrow face, which carries a dense, narrow, vertical band of long, matted, bristly pile extending from the antenna to the gibbosity and then extending down over the gibbosity to form an especially dense, matted, triangular tuft. Related to A plestobroma Hull through the similarly produced hypandrium. Length 13 to 15 mm.
Head, lateral aspect: The upper three-fourths of the face is nearly plane with the eye level; on its lower portion the face presents a low, rounded retreating elevation not extending forward beyond the upper plane of the face. The eye is long, strongly convex anteriorly, nearly plane through the middle portion behind, and not recessed. The occiput is moderately thick and continues undiminished to the upper por- tion of the head where it slopes gradually to the eye margin. Pile of occiput extremely long, fine, and mat- ted dorsally, and extending far above the vertex and mesonotum; the individual hairs are three-fourths as long as the antenna. Pile along the middle of the occiput also long, fine and bristly and directed outward, but less abundant. Ventral pile shorter but abundant and matted, true bristles are absent. The proboscis is small, short, gradually swollen towards the stout base; it is dorsoventrally depressed towards the apex and therefore in profile appears rather narrow apically and especially tapered and oblique on the lower portion. This lower portion bears laterally some long, stiff setae, but only a few minute hairs dorsally at the apex; the base ventrally has a number of long, slender bristles directed obliquely forward, together with weaker hairs. The proboscis is directed obliquely downward. The palpus is distinctly composed of two segments, the second segment generally held at nearly a right angle. The first segment is short, distinctly hemicylindrical and excavated, pilose below. The second segment is club-shaped, relatively short, narrowed basally and carries a number of long, stiff bristles ventrally and apically. It appears to lack a pore.
PART 1
Antenna attached at the upper fifth of the head, un- usually slender and distinctly longer than the head. The first two segments combined are as long as the third segment, its microsegment excluded. The second segment is two-thirds as long as the first segment and apically widened. Third segment quite slender, a lit- tle swollen at the immediate base and slightly tapered just before the apex which is ventrally and obliquely truncate. This segment carries a long microsegment held at a slight angle, the microsegment is approxi- mately a little less than one-third as long as the third segment, and at its apex it has a ventral, spoonlike or hoodlike extension which contains a long, dorsal, spinous bristle. Pile of the first antennal segment confined almost entirely to the ventral surface with no dorsal pile; it carries a dense, exceptionally long fringe of stiff, bristly hairs fully as long as the third antennal segment. This fringe is more or less matted and extends from base to apex. Apex of second seg- ment with fine, long setae above and 6 long, stout bris- tles below, matted and similar to those of the first segment.
Head, anterior aspect: The head is nearly circular. The face width below antenna is one-tenth the head width, widening below to nearly one-third. The sub- epistoma is short, oblique and nearly plane. Face with a narrow, vertical, dense, matted band of exceptionally long, slender, bristly pile, extending from the antenna to the upper slope of the low gibbosity. This pile is nearly as long as the antenna and might be described as weak bristles. On the gibbosity there is medial, similar, bristly hair which extends out over the whole surface, except its lateral margin, but comparatively long, because of the length of the head, and is only a little wider than the upper face. The sides of the front have dense, long, matted pile similar to that on the face, but only a little longer than the length of the first two antennal segments. The vertex is scarcely excavated, the ocellarium large, low, with swollen ocelli and bearing a number of fine, long, bristly hairs. An- terior eye facets slightly enlarged.
Thorax: The thorax is densely, coarsely micropubes- cent. The mesonotum is only abrupt anteriorly, but has a rather high, slightly narrowed and arched appear- ance. Cover of mesonotum consists of numerous, very long, fine bristles down the middle of the mesonotum and some shorter bristles submedially. The acrostical bristles are numerous, long and slender and subap- pressed, the dorsocentral bristles are short on the ante- rior third, becoming extremely long and numerous opposite the wing and near the postalar callosity, changing from a narrow, double row to spread out over the entire prescutellar area. Humerus short, fine, ap- pressed pilose, with a few scattered, erect hairs. Lat- eral margin of the mesonotum with many moderately long, fine, erect, bristly hairs. The notopleuron with 2 long, slender bristles, the supraalar area with 1, the postcallosity with 2 or 3 bristles, the scutellum with a wide band containing many rows of extremely long,
DASYPOGONINAE
slender bristles more or less matted together and with some long, coarse pile along the ventral margins. The scutellum is small, with a flat disc, and lying close to it are a number of stiff, bristly hairs projected back- ward from the immediate, overhanging, prescutellar margin; its disc seems to be without pile, but is pubes- cent. Propleuron with a long, fine tuft of pile. Mesopleuron without pile, except on the anterior pro- longation. Upper sternopleuron and the pteropleuron with 8 to 10 fine, long, erect hairs. Hypopleuron with- out pile, but with a differentiated patch. or spot of micropubescence. Metapleuron with a wide band of long, stiff, very slender bristles or bristly hairs. Meta- notal slopes micropubescent only; metasternal slopes and the metasternum both with numerous, fine, long hairs; postmetacoxal area very short and limited but distinctly membranous. Basalare with long, stiff setae.
Legs: All the femora and tibiae slender. The hind femur and tibia especially slender and elongate. This femur bears 8 bristles, including one at the apex and 2 weak, dorsomedial bristles at apex. Ventrally is a moderately abundant fringe of long, fine, stiff hairs. The hind tibia carries 2 moderately long, curved, oblique, dorsolateral and 6 or 7 longer dorsomedial, and 5 moderately long, ventrolateral bristles. The ap- pressed, ventral brush of setae extends to the middle. Hind basitarsus considerably swollen and robust, a lit- tle longer than the next 3 segments. Middle femur with 2 bristles posteriorly at the apex, a fringe of stiff pile below; its tibia bears 5 long, slender, attenuate, postero- dorsal bristles, but the 6 anterodorsal and 2 ventral bristles are exceptionally long, a little curved, oblique, and fully three-fourths as long as the tarsi. Anterior femur with copious fringe of stiff pile ventrally. The tibia with 4 or 5 bristles dorsally and 2 long, posterior bristles. Apex of tibia without spur. All tarsi bear well developed pulvilli; empodium half the length of the sharp claws.
Wings: The wings are hyaline, the marginal cell widely open. Second submarginal cell strongly arched at its base; the anterior branch of the third vein ends at wing apex; the posterior branch well behind apex. The first posterior cell is fully open; both end veins of discal cell long. Fourth posterior cell narrowed to two-thirds of its maximum width; anal cell widely open; second basal cell ends in 3 veins, Alula narrow and linear; ambient vein complete.
Abdomen: The slender abdomen is somewhat com- pressed laterally and as long as the wings. The first tergite is a little swollen laterally. Seven tergites present in the male with the eighth present as a short, linear flap. Pile of abdomen more or less appressed dorsally; on the posterior half of the abdomen the pile is setate but long, fine and curled on the first three ter- gites and the sides of the fourth. Sternites with stiff, long, bristly hairs in contrast to the tergal pile. All tergites without bristles. Male terminalia moderately large and conspicuous, fully rotate; the hypandrium
ROBBER FLIES OF THE WORLD 39
extends from the dorsa] margin as an extended, narrow
process curled down over the apex of the terminalia.
| Distribution: Australian: Broticosia rapaw Hull 1957).
Pegolabrus, new genus
Type of genus: Pegolabrus paramonovi, new species.
Slender flies of medium size, with faint brassy reflec- tions from the abdominal tergites. Related to Brotico- sia Hull but differing in the presence of long, bushy pile on the disc of the scutellum. Fourth posterior cell closed and stalked. Length 14 mm., including antenna.
Distribution: Australian: Pegolabrus paramonovi, new species.
Pegolabrus paramonovi, new species
Male. Head: The head is circular from the anterior aspect. with very narrow upper face, which widens be- low. Front and vertex also narrow but a little wider than the upper face. The head is black throughout in ground color. Pile of upper occiput rather dense, ex- ceptionally long, fine and black. There are numerous, similar, long, fine, black hairs arising from the large ocellar triangle, which is nearly equilateral in shape. Sides of front with a tuft of long, fine, black hairs. Antenna slender, elongate and black. Surface of face densely covered with pale, yellowish white, appressed micropubescence, which is rather whitish on the sides of the low, facial gibbosity. The medial half of the face has a vertical band of dense, remarkably long, fine, black hairs in matted tufts. These tufts of hairs diverge along the sides of the facial gibbosity below and are equally long but somewhat less dense. These ventral hairs enclose a tonguelike tuft of matted, long, pale yellow hairs. In the midline at the bottom of the face above the epistoma is another tuft of dense, matted,
~ long, black hairs. Proboscis short, shining black and
bluntly rounded. It is directed downward but if ex- tended forward it would reach but little beyond the epistoma, if at all. Palpus of two segments, the first of which is excavated, the second short, robust, with numerous, fine, black hairs. Both segments are black. The central portion of the upper occiput on its lower part has considerable long, fine, yellowish white hairs. Laterally the lower third of the occiput has some quite short, yellowish white hairs.
Thorax: The mesonotum is black, obscurely shining across the middle, a little more polished opposite the wings and with a large, more or less triangular patch of minute, greyish white micropubescence which is al- most pollenlike on the anterior half of that part of the mesonotum in front of the suture. This fine micro- pubescence extends as a rather wide marginal band along the sides of the mesonotum and medial to the postalar callosity. Viewed from above it is quite white, almost bluish white. Pile of mesonotum abundant,
40 UNITED STATES NATIONAL MUSEUM BULLETIN 224
exceptionally fine and unusually long and erect, this pile longer and somewhat more conspicuous on the posterior third of the mesonotum, and with a rather conspicuous patch of similar, equally long pile on each side of the disc of the scutellum which is also black in color. Ventral margin of scutellum, upper mesopleu- ron and propleuron with abundant, long, fine, white hairs. Metapleuron with a vertical band of some 20 similar bristly hairs.
Legs: The legs are slender; anterior femur with the basal half and middle femur with the basal fifth shin- ing blackish, the color diffusely delimited. Apex of the first four tibiae narrowly black and all the basal segments quite black. Remainder of these tibiae and their femora light orange brown. Hind legs missing. Pile of the middle femur quite fine and erect, chiefly pale and long ventrally, but with a few quite long, black hairs intermixed and with some short, black hairs dor- sally on the outer third, besides 1 or 2 slender, black, dorsal and apical bristles. Middle tibia with 7 oblique, long, quite slender, black bristles and 4 still longer, stouter, pale yellow, anterodorsal bristles; 5 posterior yellow hairs that are long and bristly; 2 long, stout, posteroventral, yellow bristles; and 1 similar, basal, anteroventral bristle. Anterior femora with quite abun- dant, long, exceptionally fine, erect, blackish hairs from the dorsal, posterior, and ventral surfaces and also with abundant but rather short, fine, yellow hairs medially. Anterior tibia with the bristles short, except for 2 long, rather thick, yellow, posteroventral bristles and beyond them a single long, black, bristly hair and posterodor- sally 7 short, rather stout, black bristles and 8 similar, anterodorsal, short, black bristles. Ventral surface with numerous, very fine, erect, black hairs, which are both short and long. Bristles at the apices of the tibiae chiefly yellow. Claws slender, pulvilli long and spatu- late. Empodium quite stout at the base and pale in color.
Wings: The wings are hyaline; the veins dark sepia- brown, except basal to the humeral crossvein they are light orange-brown.
Abdomen: The abdomen is more or less compressed, shining black with a faint greenish to brassy luster similar to Broticosia rapax Hull but less pronounced. The sides of the tergites are rather densely covered with a remarkably fine, minute, pollenlike, whitish bloom or micropubescence. Pile erect, fine and yellow; es- pecially dense and long on the sides of the first 3 ter- gites, shorter in character dorsomedially and greatly reduced beyond the third tergite. Sternites with long, fine, erect pile which is mostly yellow but with some black hairs intermixed. Terminalia shining black, the proctiger basally and laterally reddish brown.
Type: Male, Dubbo, New South Wales, August 29, 1925. In the collection of Commonwealth Scientific and Industrial Research Organization, Canberra,
A.C.T.
PART 1
Genus Leptarthrus Stephens Ficures 4, 411, 807, 816, 1895, 1898
Leptarthrus Stephens, Syst. Cat. British Insects, pt. 2, p. 258, 1829. Catalog name accompanied by unnamed figure and definitive hind tarsus of a male fly. Type of genus: Dioctria brevirostris Meigen, 1804. Taken from Verrall (1909).
Isopogon Loew, Linnaea Entomologica, vol. 2, p. 492, 1847. Type of genus: Dioctria brevirostris Meigen, 1804, by mono- typy-
Small flies, characterized by a rather robust abdomen, tapered at the apex only. They have short, appressed pile with dense, long pile of the head and mesonotum. The mesonotum is high, and the face wide with paral- lel sides. These flies are distinguished in the male by the curious swordlike, thin, and laterally compressed hind basitarsus, and in the female by the slender, elon- gate, simple ovipositor formed from the narrow, tube- like sixth to eighth segments. Length 10 mm.
Head, lateral aspect: Face low and gently rounded, slightly produced beneath the antenna and protruding but little more on the lower face. Eyes strongly con- vex anteriorly, gently behind, without ventral reces- sion. Occiput prominent, moderately developed, thin- ning at vertex and again at the bottom of the eye. Occiput without bristles but with uniformly dense, long, crinkled, delicate pile; the long pile begins some distance from the eye margin. Proboscis small, short, oblique, obtuse, strongly swollen towards the base and from dorsal view acutely triangular. It has a low medial ridge and short stiff pile at the apex and in the middle laterally; at the base below are numerous long, fine hairs. Palpus distinctly of 2 segments, the first segment longer, robust, with numerous fine long hairs laterally and stiff pile below. The short, apical seg- ment is porate and bears just beyond its middle a crease which may indicate a subdivision and bears a few long slender hairs. Antenna attached just above the mid- dle of the head. The first 2 segments are short, bead- like, and equal in length. The third segment is rather long, slender, tapered from the middle to the apex and bears 2 microsegments, the first quite short, the second 3 or 4 times as long, with at its apex a distinct spine. The microsegments and third segment thickly pilose, the former held at a distinct oblique angle. First 2 antennal segments with several long stiff hairs dor- sally, the first segment ventrally and laterally with 8 or more long, slender, bristly hairs, the second segment with 2 or 3 hairs.
Head, anterior aspect: Face wide, a little more than one-fourth of head width and slightly divergent below. Face pubescent or sometimes bare in the middle and bearing numerous, long, curved, stiff pile or bristly hairs. These bristly elements extend nearly to the an- tenna and are largely directed forward; the lower elements are more numerous and curled downward. Subepistoma small, concave and not quite horizontal. The front is short, very slightly divergent, the vertex of the same width. The front bears a number of slen-
DASYPOGONINAB
der bristly hairs laterally, the vertex is only moder- ately excavated and has slanting sides. The ocella- rium unusually large and wide with all ocelli swollen. It bears 10 to 15 pairs of long, erect stiff, slightly divergent hairs. Central eye facets strongly enlarged and zoned.
Thorax: Mesonotum high and strongly arched. It is pubescent chiefly on the notopleural area and the transverse suture is strongly arched and curves back- ward. Anterior part of postcallosity, supraalar region, and the pleuron except for a bare mesopleural spot, pubescent. Pile of mesonotum rather dense and un- usually long, but fine and delicate, crinkled and subap- pressed and directed backwards. Humerus pilose. Weak lateral bristles are present as 3 or 4 slender notopleural bristles and no others. Scutellar margin with long, quite delicate hairs. The scutellum thick, convex, bare and shining except for pubescence on the lower marginal rim. Propleuron with dense, long, delicate pile, including the collar. Upper mesopleuron with numerous fine hairs, sternopleuron with 2 hairs, pteropleuron and hypopleuron micropubescent only, metapleuron with a band of long, fine, delicate pile above which are a few, stiff, slightly bristly hairs. Metanotal slopes micropubescent only, metasternal slopes and the metasternum with abundant quite long, fine pile; postmetacoxal area membranous.
Legs: The femora are only slightly stout, the hind pair barely dilated on the apical half. The hind tibia is stout but straight. The hind femur bears appressed setae above, 8 bristly hairs medially at apex, 3 weak bristles dorsolaterally at apex, and a rather abundant, ventral fringe of long stiff hairs. The hind tibia bears 8 or 9 moderately long, sharp, oblique, dorsal bristles, 2 dorsolateral at the base, 2 lateral in the middle, 2 or 3 long bristly hairs medially and an oblique ventral fringe of stiff hairs. The apex has 1 dorsal, 3 lateral, 3 medial, and 4 ventral bristles. Hind basitarsus in the male extended into a very slender, distally attenuate, laterally compressed, thin process which is longer than the femur itself. The remaining tarsal segments min- ute, greatly shortened, except that the last one is a little swollen. The female basitarsus, while elongate and nearly as long as the remaining segments, is robust and cylindrical and in no way abnormal. Middle femur with appressed pile above, 2 small bristles anteriorly near apex, and a copious fringe of long, stiff bristly pile below. The middle tibia bears the following bristles: 10 short dorsal above, which are oblique, sharp, and basally stout; 2 anterior on the basal fourth; 8 or more long, slender posterior and 6 or 7 equally long postero- ventral bristles. It also has 6 slender ventral and the same number of slender, longer anteroventral bristles; apex with stout spines only below. The anterior femur is similar to the middle femur; its tibia bears 8 short stout posterodorsal, 8 to 10 shorter anterodorsal, 4 or 5 slender posterior, but with 2 additional stouter ones on the outer third. It also has a few long slender postero- ventral, some similar ventral and 2 stout, long bristles near the apex. Apex of anterior tibia with a short,
ROBBER FLIES OF THE WORLD 41
sharp, slender, curved spine. Pulvillus as long as the claws; empodium fine, about half as long as the pulvillus.
Wings: The marginal cell widely open, all posterior cells widely open, anal closed and stalked, second basal cell closed by three veins. Alula moderately devel- oped; ambient vein complete.
Abdomen: The abdomen is rather robust, slightly wider at the end of the second and third tergites, where it is wide as the mesonotum; it is slightly tapered on the fourth tergite; considerably tapered on the fifth tergite. Seven tergites present in the male, the seventh at least half as long as the sixth, which is only slightly reduced. Female with only five well developed tergites, the sixth, seventh and eighth are quite small, short, dorsoventrally flattened and together form the ovipositor. Pile of abdomen dense, subappressed and setate with consider- able, long, radiating, fine pile on the sides of tergite two and some long pile laterally on tergite one. Bristles absent. Sides of abdomen rolled; the sternites with abundant, long, fine pile; the tergites are, therefore, quite convex. Male terminalia small and short and not rotate. The epandrium is downturned, arched and hoodlike. The gonopod is well developed but the hy- pandrium is greatly reduced. Dorsal proctiger with deep, linear, medial fissure.
Distribution: Palaearctic: Leptarthrus brevirostris Meigen (1804) [=apicalis Rossi (1840), armillatus Fallen (1814), longitarsis Fallen (1814) |; vitripennis Meigen (1820) [=elatus Meigen (1820), ?hottentottus Fabricius (1794), hyalipennis Meigen (1804) not Fabricius].
Ethiopian: Leptarthrus parvulus Bigot (1859).
Country unknown. Leptarthrus volcatius Walker (1849).
Ricardo (1912b), points out that Dasypogon volca- tius Walker does not properly