440 



UNITED STATES NATIONAL MUSEUM BULLETIN 224 



Tribe Asilini 



In the Asilini many genera have pile or bristles on 

 the lateral slopes of the metanotum; others have it 

 bare. Likewise the genera fall mto 2 gi-oups with re- 

 spect to the scutellum, which may be flattened with 

 subapical crease, or tumid and swollen without im- 

 pressed margin. Genera like Glaphyropyga Schiner 

 and Opopotes Hull, which have the metanotum bare 

 and the scutellum thin, are reckoned to be generalized 

 over those which have bristly pile or a tumid scutellum, 

 or both as in PorasUus Cun-an. The combination of 

 bristly metanotum and flattened scutellum predominates 

 in the Old World : the combination of bare metanotum 

 and tumid scutellum predominates in the New World. 

 It is possible that the genera consisting of Nerax, new 

 genus and its allies, which appear to be restricted to the 

 New World, and those related to Promachiis Loew, 

 which, except Mallophora Macquart, are common to 



both hemispheres, should each be segi-egated into tribes. 

 The Neolophonotus Engel group contains 10 genera, 

 which are characteristic of the South African region. 

 All have the metanotal callosities bare. They tend to 

 have a gently arched or convex face without a defined 

 gibbosity and with extensive, long, stiff, facial pile, 

 which occasionally fonns a facial mane. In otlier forms 

 a mesonotal mane is common. Of these genera Neolo- 

 phonotus Engel, Neodasophrys Ricardo, Hippomachus 

 Engel, Lophyhus Engel, Megadrillus Bigot and Lopho- 

 peltis Engel are readily characterized by the long, me- 

 dial crossvein or lower component of the veins ending 

 tlie discal cell. On tlie other hand, Synolcus Loew, 

 Dasophrys Loew and the allied Hohhyus Bromley all 

 tend to have this component quite short and the discal 

 cell strongly occluded and in the males an expanded 

 costa. 



KEY TO GENERA OF ASILINI 



1. Three submarginal cells 2 



Two submarginal cells, with or without ap- 

 pendiculate vein from base of the second sub- 

 marginal cell 14 



2(1). Apex of second submarginal cell strongly flared; 

 anterior branch of third vein ends at or before 

 wing apex; posterior branch ends far to the 

 rear of wing apes. First submarginal cell and 

 basal part of second submarginal cell often 



greatly narrowed. Claws acute 3 



Apex of second submarginal cell not flared and 



these cells never greatly narrowed 4 



3(2). First submarginal cell and basal part of second 

 submarginal cell greatly narrowed, and radial 

 crossvein lies near the middle of first submar- 

 ginal cell, or the cell placed in front of this 

 crossvein (Promachus Loew group) .... 8 

 First submarginal cell and basal part of second 

 submarginal cell not greatly narrowed; radial 

 crossvein occupies a more basal position {Alci- 



mus Loew group) 5 



4(2). Posterior branch of third vein ends shortly below 

 wing apex. Claws blunt. 



ElCHOICHEMUS Bigot 

 Posterior branch of third vein ends distinctly 

 above wing apex. Claws acute. 



Efferia Coquillett 

 5(3). First posterior cell closed and stalked; ocelli often 

 reduced or concealed by pubescence. 



Apoclea Macquart 



First posterior cell open 6 



6(5). Basal part of lower fork of second vein (R3) dis- 

 tinctly longer than radial crossvein (Rj). This 

 radial crossvein generally arises near or just 



before end of discal cell 7 



Basal part of lower fork of second vein (Rj) is 

 quite short, as long or barely longer than radial 

 crossvein (R*). Anterior branch of third vein 

 arises between anterior crossvein and discal- 

 cell end veins. Tenth female tergite with a 



pair of long spines and short ones. Abdomen 

 much longer than wings; slender and tapered. 



Alcimus Loew 

 7(6) . Three submarginal cells uniformly present. Third 

 antennal segment elongate, several times as long 

 as wide. Superior forceps elongate, high, later- 

 ally convex and tending to enclose the inferior 

 surface; other elements short or reduced. Ovi- 

 positor elongate, cylindrical and conical on the 

 distal part; tenth segment with numerous, short 

 spines and often a pair of apical, longer spines. 



Philodicus Loew 

 Usually only 2 submarginal cells present, with a 

 broken spur- vein; 3 rarely present; spur rarely 

 absent. Third antennal segment shorter, or, if 

 elongate, the base swollen, the apex strongly 

 attenuate. Terminalia rather similar to Philo- 

 dicus Loew, ovipositoral spines larger and more 



prominent Apoclea Macquart 



8(3). Claws acute. Face without extensive gibbosity. 



(Promachus Loew group) 9 



Claws obtuse 12 



9(8). Apex of antennal style dilate and spearlike. 



Philomachus Karsch 

 Apex of antennal st.yle slender and pointed . 10 

 10(9). Ovipositor short, the 2 halves of tenth tergite with 

 distal extremities pointed and divergent. 



Enagaedium Engel 



Ovipositor longer, not divergent at apex . . 11 



11(10). Ovipositor of medium size, incorporating the last 



3 segments Promachus Loew 



Ovipositor very long, incorporating the last 5 seg- 

 ments Tktpanoides Becker 



12(8). Ovipositor of female and terminalia of male quite 

 small. Robust and pilose flies with the abdomen 

 short and stout. Wings distinctly longer than 

 abdomen. Face and front of moderate width. 

 Tarsal segments greatly shortened .... 13 

 Ovipositor elongate, incorporating 4 or 5 seg- 

 ments; terminaUa larger. Abdomen not of the 



