LiPHEIINAB 



ROBBER FLIES OF THE WORLD 



339 





Head, anterior aspect : The face below the antenna is 

 one-fourth the head width, with parallel sides below. 

 Subepistomal area moderately large but distinctly hori- 

 zontal and not, encroaching upon the face ; it is concave 

 and bare. Face pubescent, bearing numerous, long, 

 slender, bristly hairs on the lower half or two-thirds. 

 Laterally on the upper two-thirds, the face character- 

 istically has a marginal band of prominent, bright, 

 flattened scales or scalelike pile. Antenna attached at 

 the upper third of the head and exceptionally long; 

 the first segment is 10 times as long as the second, the 

 second beadlike. The third segment is flattened later- 

 ally, a little wider or higher than the basal segments, of 

 nearly uniform height or gradually widened towards 

 the apex, which may be obliquely truncate; in the mid- 

 dle of the truncate apex it has an extremely minute 

 spine. Pile of the first segment long and bristly and 

 abundant dorsally and ventrally, becoming shorter to- 

 wards the apex. The front is short, pollinose with 

 bristly pile or weak bristles laterally. The small but 

 moderately high ocellarium has the anterior ocellus 

 low and bears 2 pairs of equally long, stout, divergent 

 bristles and sometimes 1 or 2 additional fine hairs in the 

 middle area also. The eye facets are very strongly en- 

 larged centrally. 



Thorax : The thorax is pollinose ; the pile of the meso- 

 notum is fine, bristly and erect and scanty in quantity. 

 A narrow band of acrostical elements is present; 

 dorsocentral elements are differentiated anteriorly and 

 there are a few longer, slender bristles posteriorly. 

 There is almost no lateral pile except for a small, tri- 

 angular area medial to the humerus and a narrow band 

 along the lateral margin. Humerus with stiff pile only. 

 Lateral bristles are present and consist of 1 or 2 noto- 

 pleural, 1 supraalar, 1 to 2 postalar, and on the scutel- 

 lum 4 pairs of long, slender bristles with additional, 

 shorter, bristly hairs. Scutellum moderately thick and 

 convex with a shallow basal crease, an impressed margi- 

 nal rim and with a few stiff hairs on the pollinose disc. 

 Propleuron with fine, moderately long, abundant pile 

 ventrally; anterior mesopleuron with numerous long, 

 fine hairs ; the whole upper half and the posterior bor- 

 der of the mesopleuron with abundant, long, fine pile. 

 The mesopleural bristles may be reduced to a single, 

 very slender element which is a little longer and more 

 conspicuous than the remaining pile. Pteropleuron 

 apilose; hypopleuron with pile, metapleuron with a 

 prominent, wide, vertical band of numerous, quite long, 

 slender bristles. Metanotal slopes pubescent only ; lat- 

 eral metasternum with pile, the ventral metasternum 

 with a few fine, scattered hairs. Postmetacoxal area 

 membranous though small; the sides of the metaster- 

 num encroach onto the lateral third ventrally. Tegula 

 with bristles. 



Legs : All the femora slightly thickened through the 

 middle ; on the hind femur the thickening is distributed 

 over both the dorsal and ventral halves ; on the anterior 

 and middle femora chiefly on the dorsal half. The pile 

 of the legs is quite scanty and fine, on all the femora 



short and setate and appressed dorsally but fine and 

 erect ventrally. The type of genus bears the following 

 complement of bristles: on the hind femur 5 stout, 

 tuberculate, lateral bristles and 8 similar, tuberculate 

 ventromedial bristles, all quite sharply pointed. 

 Dorsally there are 2 stout bristles and 2 or 3 weak 

 bristles situated on the apical third ; apex with 1 weak 

 medial bristle. Hind tibia as long as the femur and 

 rather slender, a little widened apically and with 6 or 7 

 short dorsal bristles, 3 or 4 slightly longer dorsolateral, 

 and a fringe of long, fine hairs medially; there is a 

 ventral brush of setae only at the apex. Middle femur 

 with a single, stout, dorsal bristle at the outer third, and 

 2 posteriorly near the apex ; the midtibial bristles are 

 long, basally stout, but finely attenuate and oblique. 

 There are 3 anterodorsal, 4 posterodorsal, 4 or 5 ventral 

 elements scarcely more than hairs, and 2 long, stout, 

 anteroventral bristles on the outer half. Anterior femur 

 with long, fine, stiff hairs dorsally and ventrally ; its 

 tibial bristles are weak and consist of 6 anterodorsal, 8 

 or 9 posterodorsal, and 4 or 5 ventral bristles. All tarsi 

 end in slender, sharply pointed, apically curved claws, 

 large pul villi, and a long, bladelike empodium not or but 

 little swollen at the base. 



"Wings: The wings are slender, the marginal cell is 

 closed with a long stalk. The anterior branch of the 

 third vein ends just above the wing apex or at the apex ; 

 the posterior branch ends a considerable distance back- 

 along the posterior margin. First posterior cell rela- 

 tively narrow and closed with a long stalk which varies 

 somewhat in length ; fourth posterior cell closed with a 

 long stalk and the anal cell likewise. Middle end vein 

 of the second basal cell short. Alula moderately wide, 

 ambient vein complete. 



Abdomen: The abdomen is slender and distinctly 

 petiolate, narrowest at the base of the second segment 

 and in the type of genus gradually tapering back to the 

 end of the fifth segment or in other species with the sides 

 of the elongate second segment parallel and the third 

 segment approximately shaped as an equilateral tri- 

 angle. In the male there are seven tergites, the seventh 

 slightly reduced in length to about one-half; in the 

 female seven tergites, the seventh two-thirds as long as 

 the sixth, the eighth tergite incorporated in the 

 terminalia. Pile of the abdomen abundant, but quite 

 short, appressed and setate. Male terminalia large, 

 elongate and conspicuous with a large, bowl-shaped re- 

 ceptacle ventrally composed of the entirely fused 

 epandrium and with an apical, thin, curved, narrow, 

 platelike extension. Hypandrium deeply sulcate but 

 fused at the base. The female terminalia consist of a 

 moderately long, dorsal, conical projection, the sides 

 somewhat compressed laterally. Ventral processes ap- 

 parently absent. 



Distribution : Neotropical : Rhopolocj aster araujoi 

 Carrera (1952) ; aurifer Hermann (1912) ; bella Brom- 

 ley (1929) ; fascipennis Hermann (1912) ; Uneata Her- 

 mann (1912); longicomis Wiedemann (1828); 

 niphardis Hermann (1912). 



