52 



UNITED STATES NATIONAL MUSEUM BULLETIN 22 4 



open, the simple, tubular and not spiny female termi- 

 nalia, the absence of spines on the anterior tibial apex. 

 There are exceptionally deep, mediogenal grooves cor- 

 responding to the anterior arms of the tentorium. In 

 some of the flies the lower face is strongly suggestive 

 of the Rhagionidae. The antenna is of 2 kinds. In 

 Damalis Fabricius and its allies the third segment is 

 small, beadlike, with a very long, fine style or arista ; in 

 Holcocephala Jaennicke and related genera the third 



segment is elongate, with 1 or 2 short microsegments 

 and the arista quite stout or lacking. Representatives 

 of both groups occur in each hemisphere. 



There is no rational basis whatever for the recogni- 

 tion of a special tribe Trigonomimini as proposed by 

 Enderlein, 1914, based on the presence of 4 submarginal 

 cells, even in part for the inclusion in it of unrelated 

 genera like Trigonomima Enderlein and Townsendia 

 Williston. 



KEY TO GENERA OF DAMALINI 



1. Only 4 submarginal cells; hind femur and tibia rather 



smaller and bearing dense brushes of rather long, fine 



pile Trigonomima Enderlein 



Five submarginal cells present 2 



2. Third antennal segment consists of a small, dilated, bulblike 



basal piece, drawn out apically into an extremely long, 



bristlelike style, longer than the head 10 



Third antennal segment elongate and well developed, with 

 several types of terminal structures 3 



3. Microsegments absent at apex of third antennal segment; 



apex of this segment bearing a moderately long, apical 

 or subapical bristle and above it a short, spinous bristle, 

 which is apical, more usually subapical to a varying extent. 

 Third segment short or long pubescent but never plumose. 



Damalina Doleschall 

 Apex of third segment bearing distinct microsegments . . 4 



4. Third antennal segment quite long, with 2 equally wide, 



cylindrical, short, plumose microsegments whose com- 

 bined length is greater than the length of the third segment. 

 Wing very broad. Small flies with broad, oval, compar- 

 atively flattened abdomen Margaritola Hull 



Microsegments of third antennal segment much shorter and 

 not forming a long, densely pubescent, cylindroid struc- 

 ture 5 



5. Apex of third segment with a single microsegment .... 6 

 Apex of third segment with 2 distinct microsegments, the 



more basal element shortest 7 



6. Hind feumr, tibia and basitarsus enlarged and bearing a 



dense brush of long hairs . . . Arthriticopus Enderlein 

 Hind femur, tibia and basitarsus simple. 



Holcocephala Jaennicke 



7. Ocellarium with enlarged ocelli and both prominently 



protruded forward beyond the eye profile; occiput prom- 

 inent 8 



Ocellarium and its ocelli not extending beyond the eye profile 

 margin. Occiput poorly developed . Oxynoton Jannsens 



8. Third antennal segment comparatively short, more or less 



attenuate distally, second microsegment bearing a short, 

 apical style; both microsegments not plumose; third 

 antennal segment with several long, plumose to bristly 



hairs dorsally Haplopogon Engel 



One or both of the third antennal microsegments conspic- 

 uously short plumose 9 



9. Basal microsegment not plumose; second microsegment 



without thick spine; third antennal segment compara- 

 tively short, distally attenuate . Paroxynoton Jannsens 

 Both microsegments usually plumose; second microsegment 

 with a thick spine; third segment usually elongate; face 

 usually with numerous, quite long, bristly hairs, which 

 are extended forward .... Rhipidocephala Hermann 

 10. Third antennal segment fully as wide as the second segment 

 and pollinose or micropubescent; postmetacoxal area 

 membranous 11 



Third antennal segment distinctly and considerably more 

 slender than the second segment and polished and bare, 

 beadlike or more rarely attenuate, and always tapering at 

 the apex into the long drawn out style 12 



11. Third antennal segment as large as basal segments and 



about twice as long and pollinose. Front normal, face 

 divergent below. Head long on the lower portion, ob- 

 liquely flattened above; the facial crease is especially deep. 

 Abdomen short oval. The distally dilated hind femur 

 has a dense brush of fine hairs. Upper section of anterior 

 intercalary vein very short or wanting. Base of fourth 

 posterior cell without a petiole .... Orrhodops Hull 



Third antennal segment short, nearly orbicular, consider- 

 ably larger and wider than the second segment. Front 

 with a longitudinal sunken area and upper face with a 

 longitudinal furrow. Mesonotum very densely pilose, 

 the pile virtually concealing the ground color. Upper 

 section of anterior intercalary vein long; last section of 

 fifth vein nearly vertical . . . Bromletus E. Hardy 



12. All the coxae so drawn forward that they stand in a nearly 



vertical row beneath the anterior margin of the mesono- 

 tum, the arched band of chitin behind the posterior coxa 

 exceptionally long; mesonotum with long, slender bristles. 

 Head wide and short, the face plane, with numerous, 

 long, stiff hairs on the lower half and bristles absent (sub- 

 genus of Damalis Fabricius) . Ztgocolon, new subgenus 

 Coxae placed in more or less the usual position beneath 

 the mesonotum 13 



13. Apex of middle tibia with a short but prominent spur or 



lobe, bearing numerous spinelike bristles; sides of abdo- 

 men with a fringe of dense, long, fine pile which is dense 

 but shorter across the middle of the segments. 



Lophurodamalis Hermann 

 Apex of middle tibia simple 14 



14. Sides of mesonotum with distinct bristles; male terminalia 



with a downwardly directed process. 



Lasiodamalis Hermann 



Sides of mesonotum without distinct bristles, usually with 



fine or stiff pile; rather bare, short pilose flies .... 15 



15. Face short, nearly plane, with a row of strong bristles along 



the oral margin and little or no pile; ocelli set anteriorly 



before the vertex 16 



Face strongly gibbous, convex and rounded and bearing 

 numerous stiff bristles and bristly hairs over the whole; 

 ocellar protuberance large, set on the vertex; proboscis 

 narrow but unusually short and obtuse, its base con- 

 siderably swollen (subgenus of Damalis Fabricius). 



Protodamalis, new subgenus 



16. Upper margin of occiput produced backward and upward 



into a conspicuous flange; anterior dorsal part of mesono- 

 tum expanded and greatly swollen .... Aireina Frey 

 Occiput in no way unusual; mesonotum high but regularly 

 arched anteriorly and posteriorly . . Damalis Fabricius 



