ROBBER FLIES OF THE WORLD 



441 



short and robust pattern. Wings as long as 

 abdomen or shorter. Face and front narrow. 

 Promachina Bromley 

 13(12). Face usually strongly gibbous ventrally. Pile 

 scanty and loosely scattered on upper 

 face Mallophoea Macquart 



Face gently convex, uniformly pilose, the oral 



margin with bristles. First posterior cell open, 



or closed and stalked . Megaphokus Macquart 



14(1). Base of second submarginal cell with an appendi- 



culate vein (remains of vein Rs) 15 



Base of second submarginal cell, R4, never with 



spur vein 23 



15(14). Slopes of metanotal callosity bristly pilose; face 

 strongly gibbous below 16 



Slopes of this callosity bare 17 



16(15). First posterior cell extremely long, narrow, con- 

 cave anteriorly. Convex posteriorly, tlie apex 

 likewise narrow . . . Ntssomyia, new genus 



First posterior cell dilated and flared apically ; first 

 branch of the fourth vein meets wing margin far 

 to the rear of wing apex . . Porasilus Curran 

 17(15). Second submargin.al cell stronglj' flared apically, so 

 that first branch of the fourth vein meets wing 

 far to the rear of wing apex; apex of arista 

 slender 18 



Second submarginal ceU narrow apically. First 

 branch of fourth vein ends near wing apex; male 



terminalia very large 19 



18(17). Front and vertex strongly convergent above. 

 Base of antennal arista with a microsegment. 

 End veins of second basal cell never fused 

 beyond. Face prominent below but scarcely 

 gibbous; mystax exceedingly stout. Tergal 

 bristles confined to first segment. Base of 

 second submarginal cell narrowed. 



Anacinaces Enderlein 



Front and face not distinctly convergent above. 

 Antennal microsegment absent. Mystax slen- 

 der. Pile of upper face abundant, coarse, 

 often appressed. Female ovipositor with prom- 

 inent spines. Tergal bristles present on several 

 tergites. First posterior cell usually open; 

 sometimes closed .... Apoclea INIacquart 

 19(17). Anterior branch of fourth vein ends before, at, or 

 slightly beyond apex of wing. Arista simple at 

 apex; never with spatulate or distinctly widened 

 tip 20 



Anterior branch of fourth vein ends quite 

 distinctly beyond apex of wing. Soutellum 

 inflated, without crease; metanotal slopes 

 without pile. Arista with apex slightly 

 flattened or widened at apex, or in some 

 cases strongly widened and spatulate at 



apex Lecania Macquart 



20(19). Marginal and submarginal cells closed. 



DiPLOSYNAPSis Enderlein 



Only the marginal cell closed 21 



21(20). Posterior branch of third vein and anterior branch 

 of fourth vein each end close to wing apex, one 

 above, the other below and nearly equally distant 

 from apex. Face only moderately produced 

 below. Terminalia with superior forceps 

 apically widened, convex, curved inward to- 

 ward the middle and enclosing a space. Female 

 with ovipositor short; eighth segment conical or 

 cyhndrical Eicherax Bigot 



Posterior branch of third vein meets at or above 

 wing apex and always far from anterior branch 

 of fourth vein. Male terminalia without 



dorsal, enclosed space 22 



22(21). Male ternxinalia with a deep, lateral cleft dividing 

 each half of superior forceps into upper and 



lower prongs. Flies with robust, strongly 

 tapered abdomen . Cratolestes, new genus 

 Male terminalia large, elongate, uncleft. More 

 slender flies; females vnth long, flattened ovi- 

 positor Nerax, new genus 



23(14). Third antennal segment short, high, 3 or more 

 times height of the second segment. Males 

 with a flared and greatly expanded microseg- 

 ment Cerozodus Bigot 



Third antennal segment and microsegment, if 

 present normal 24 



24(23). The apex of style or arista dilated and thickened, 

 or spearlike and flared in both sexes, less so in 

 females. Scutellum puffed, without crease, 

 without bristles. Metanotal callosity with 



pollen only 25 



Style of third antennal segment simple at apex; 

 with few exceptions, the scutellum is marked by 

 a distinct, apical crease 26 



25(24). Aristal apex strongly flared. . Lecania Macquart 

 Arista either slightly or sometimes strongly 

 thickened distally. Male terminalia sometimes 

 greatly enlarged; female ovipositor elongate, 

 laterally compressed on last 3 segments (sub- 

 genus of Lecania). . . . Pachtchaeta Bigot 



26(24). Posterior branch of third vein ends at or behind 



wing apex 44 



Posterior branch of third vein ends distinctly 

 above wing apex 27 



27(26). Lateral metanotal callosity bristly pilose. Second 

 submarginal cell exceptionally -nide at base or 

 middle, strongly expanded anterobasally and 

 posterobasally and several times wider than 

 opposite portion of first submarginal cell; apex 

 narrow, ambient vein often absent or depauper- 

 ate 28 



Lateral metanotal callosity bare. Second sub- 

 marginal cell not exceptionally expanded; 

 ambient vien present 31 



28(27). Anterior basitarsus exceptionally long, 2 or more 

 times as long as succeeding segments. Ambient 



vein present Eccoptopus Loew 



Anterior basitarsus of ordinary length ... 29 



29(28). Short, robust flies; wings reach approximately to 

 apex of the abdomen ; length 25-30 mm. . 30 

 Elongate, strongly tapered, large or very large 

 flies; abdomen extends beyond apex of ^\angs. 

 Female terminalia densely beset with short, 

 stout spines. Vertical recess deep; vertex con- 

 vergent. Ambient vein absent in some species 

 and posterior veins often evanescent. 



Sa TANAS Jacobson 



30(29). Ambient vein absent, posterior veins evanescent; 

 wings short and broad. Blue-black to violet- 

 black flies, including wing . PoLYSARCASchiner 

 Ambient vein present . Polysarcodes Pararaonov 



31(27). Third antennal segment 6 to 8 times as long as 

 wide; style no longer than, and sometimes 

 shorter than, second segment; female terminalia 

 quite elongate and cylindrical, eighth tergite 



especially long Apotinocerus Hull 



Third antennal segment short; style long ... 32 



32(31). Males 33 



Females 39 



33(32). Third vein branches before end of discal cell. 

 Face below gibbosity and lower occiput with 

 long, dense pile. Anterior crossvein oblique. 

 Wings reach or extend beyong tip of abdomen. 

 Large flies of usually short, robust abdomen. 

 EccRiTosiA Schiner 

 Third vein branches beyond end of discal cell . 34 



34(33). Face with a shallow concavity below antenna. 

 Costa or marginal cell never expanded. Ab- 

 domen reaches bejond tip of wings. Large or 



