DASVrOGONINAE 



ROBBER FLIES OF THE WORLD 



127 



are some much longer and slender, bristly hairs. The 

 lateral bristles are very stout, and pale and consist of 



3 notopleural, 1 postsupraalar, 2 postalar, with addi- 

 tional long pile, and 4 pairs of scutellar marginal 

 bristles, of which the alternate pairs may be black. 

 Scutellar surface is flat and transversely striate, bear- 

 ing 15 to 20 long, fine, erect hairs. The propleuron 

 bears abundant, long, fine crinkled pile. Pronotum 

 without bristles but with dense, long pile. The upper 

 sternopleuron and posterior half of the mesopleuron 

 each bear 20 to 30 long, crinkled hairs. Pteropleuron 

 with 4 or 5 short, fine hairs. Posterior hypopleuron 

 with 4 or 5 fine hairs, and no clear patch spot of pubes- 

 cence. Metapleuron with pile anteriorly and a broad, 

 middle, oval area bearing numerous, fine, long, slender, 

 pale bristles. Metanotal slopes bullose and micro- 

 pubescent only. Lateral slopes of metasternum with 

 long, fine pile. Metasternum with very abundant, long, 

 fine pile; postmetacoxal area membranous; tegula 

 pubescent only. Presternum fully dissociated. 



Legs: The legs are stout without being especially 

 thickened ; the hind femur bears appressed, sharp setae 

 above and laterally, changing to scattered, fine, long 

 hairs below which ventrally and ventromedially form 

 a fringe of long hairs. This femur bears 2 dorsal and 

 2 medial bristles, confined to the outer half and none 

 close to the apex, and also 4 lateral and 8 ventral 

 bristles. The hind tibia bears a few, scattered setae 

 above and a few, fine hairs below besides a dense, medial 

 brush of appressed setae which begins before the 

 middle. This tibia bears very stout bristles as follows : 



4 dorsal, 4 lateral, 7 ventrolateral, and 7 ventromedial 

 bristles; these last are for the most part shorter than 

 the remainder. The apex has 1 dorsal, 2 medial, 2 

 lateral, and 4 ventral bristles. Middle femur with long 

 pile everywhere on the basal half and setae dorsally on 

 the remainder and stout bristles as follows : 3 anterior 

 on the basal half, 2 posterior, 1 dorsal, and 1 anterodor- 

 sal bristle situated at the outer third. The middle 

 tibia bears 4 anterodorsal, 3 posterodorsal, 5 postero- 

 ventral, 2 very long ventral, and 4 long, anteroventral 

 bristles. The apex bears 10 bristles. Anterior femur 

 with a posterior bristle at the outer fifth and an an- 

 terior bristle near the apex; elsewhere with abundant, 

 very long, crinkled pile. The anterior tibia bears 4 

 short, stout bristles anterodorsally, 3 posterodorsally, 3 

 posterior and 2 quite long posteroventral bristles ; the 

 apical circlet of spines is similar to the midtibia; no 

 apical spine present. All tarsi end with long pulvilli, 

 stout basally swollen empodium, half as long as the 

 claw, and sharp, apically bent claws. 



Wings: The wings are subhy aline; the marginal cell 

 is open, the anterior branch of the third vein ends dis- 

 tinctly before the apex; the fourth posterior cell is 

 open but narrowed. The second basal cell ends in 3 

 veins; the middle vein is quite short and the anal cell 

 narrowly open. Alula large; ambient vein complete. 



Abdomen : The abdomen is cylindroid, rather slender 

 and slightly club-shaped at the apex in males. Wing 



535914— C2— pt. 1 in 



and abdomen of the same length. The first tergite is 

 somewhat swollen and expanded laterally. There are 

 7 well developed tergites in the male, the eighth is quite 

 short and only to be noted laterally ; the second to fifth 

 are longer than wide. Eight tergites are present in 

 the female. The pile of the abdomen is minute and 

 short dorsally, except upon the first and the base of 

 the second tergite; it is quite sparse in the female, but 

 more dense in the male, where it is subappressed and 

 setate. Sides of first, second, and third tergites with 

 abundant, fine, long, erect, crinkly pile. Bristles re- 

 stricted to the first tergite which has 1 to 3 pairs of 

 stout, long, pale bristles. Sternites with long, fine pile, 

 the first excepted. Male terminalia large but short, 

 obtuse, and clublike, with complete rotation. There is 

 a large, convex, bowl-shaped, undivided hypandrium 

 which is situated dorsally and is fully as long as the 

 epandrium. The epandrium appears to be fused or 

 nearly fused, with the smaller, shorter gonopod lying 

 midway between the upper and lower elements. The 

 epandrium is conspicuous, divided almost or quite to 

 its base and a little divergent so that the proctiger lies 

 in between. Both epandrium and hypandrium tend 

 to turn inward at the apex so that the interior struc- 

 tures are tightly enclosed. Female terminalia short 

 with 6 pairs of extremely stout, blunt spines. 



Distribution : Australian : Neoscleropogon elongatus 

 Macquart (1846) [=agave Walker (1854), digentia 

 Walker (1849), favifacies Macquart (1849), fraternus 

 Bigot (1878), lanatus Walker (1854), thai plus Walker 

 (1854)]; nicoteles Walker (1849^. 



Genus Rhacolaemus Hermann 



Figures 119, 455, 918, 927, 1751, 1849, 1979 



Rhacolaemus Hermann, Zeitschr. syst. Hymen, und Dipt., vol. 

 7, p. 12, 1907. Type of genus : Rliacotaemus variabilis Her- 

 mann, 1907, by monotypy. 



Comparatively small flies with circular head from 

 the anterior aspect and relatively short antenna no 

 longer than the head. The third segment bears 2 micro- 

 segments, the second is attenuate and apically pointed. 

 The face is unusually narrow and the lower facial 

 bristles few in number but stout. Second submarginal 

 cell of wing short. Length 10 to 12 mm. 



Head, lateral aspect : The head is long, strongly con- 

 vex both anteriorly and posteriorly. The occiput is 

 prominent throughout but especially below and bears 

 moderately abundant, long pile and dense pollen. The 

 upper half of the occiput has some 20 short, moderately 

 stiff bristles on each side. The proboscis is rather 

 short, not as long as the mystax, and distinctly com- 

 pressed laterally, but only towards and at the apex. 

 Apex with a few hairs, the base with long pile below. 

 Palpus of two segments, subcylindrical, the second seg- 

 ment acutely conical, its apex narrowly truncate but 

 apparently not perforated; the ventral surface bears 

 a few, moderately long, slender, yellow hairs, with none 

 at apex. 



