LAPIIKIINAE 



ROBBER FLIES OF THE WORLD 



355 



pubescent, everywhere covered with long, matted, 

 coarse or bristly pile which becomes slender bristles 

 over the epistomal margin and which reach to the apex 

 of the proboscis. Front pollinose, with a large tuft 

 of stiff, bristly pile opposite the ocellarium and con- 

 tinued as a narrow band down the ocular margin. The 

 vertex is deeply excavated, the ocellarium very large 

 and wide bearing depressed ocelli and a pair of mod- 

 erately long, stout bristles and a few other shorter 

 hairs. Central eye facets considerably enlarged. 



Thorax: The pleuron is chiefly appre&sed micropu- 

 bescent except on the anterior mesopleuron and sterno- 

 pleuron. The mesonotum bears similar micropubes- 

 cence laterally and narrowly along the suture and in 

 front of the scutellum and on a posthumeral band. 

 The pile of the mesonotum is rather sparse and short, 

 flat appressed and setate ; acrostical elements are poorly 

 differentiated ; all the pile transversely in front of the 

 scutellum is a little longer and bristly. The lateral 

 bristles consist of 1 notopleural, 4 or 5 supraalar with 

 other more slender elements above the postalar region. 

 The postalar region has 3 bristles ; the scutellar margin 

 1 or 2 short pairs of slender bristles and some bristly 

 hairs. Scutellum thick, convex, pubescent with bristly 

 pile. Propleuron anteriorly and posteriorly with bristly 

 pile. Pronotum with 7 pairs of quite stout bristles; 

 mesopleuron posteriorly with 1 stout bristle and with 

 coarse, appressed pile dorsally and posteriorly and con- 

 tinued on to the sternopleuron anteriorly and posteri- 

 orly. Pteropleuron with a tuft of stiff hairs ; hypopleu- 

 ron pilose; metapleuron with a vertical band of 10 or 15 

 long bristles. Metanotal slopes micropubescent only. 

 Lateral metasternum pilose; ventral metasternum 

 chitinized, at most with 3 or 4 hail's ; postmetacoxal area 

 membranous ; tegula with bristles. Presternum not dis- 

 sociated, slightly narrowed posterolaterally. 



Legs : All the femora are greatly thickened, the hind 

 pair is especially thickened subapically and its pile 

 is rather short appressed and setate for the most part. 

 The bristles on the hind femur consist of 1 dorsomedial 

 and 1 dorsolateral apical and 1 dorsolateral subapical ; 

 also 1 lateral at the outer fifth and 2 ventral bristles, 

 1 at the middle and 1 beyond ; the ventral pile is fine, 

 moderately long, scanty and erect. Posterior tibia 

 with a scanty, erect, ventral fringe and a brush of 

 setae distally; its bristles consist of 4 dorsal and 3 or 

 4 lateral elements. Middle femur with 1 stout bristle 

 anteriorly at the outer third, 1 weak bristle posteriorly 

 near the apex; its tibia has 3 or 4 weak dorsal bris- 

 tles, 3 rather short, posteroventral bristles excluding 

 the apical bristles, and with 3 or 4 moderately long, 

 ventral bristles. Anterior femur without bristles; its 

 tibia has 4 or 5 dorsal and 3 or 4 weak posterior bris- 

 tles. All tarsi end with stout, moderately sharp claws, 

 long pulvilli and long, stout, bladelike empodium. 



Wings : The marginal cell closed with a long stalk ; 

 the anterior branch of the third vein is sigmoid and 

 ends well above the wing apex and is strongly arched 

 at the base. First and fourth posterior cells and the 

 anal cell each closed with a long stalk. Middle vein 



of the end of the second basal cell moderately long. 

 Ambient vein either absent or greatly reduced; alula 

 large. 



Abdomen: The abdomen is broad and robust and 

 wider than the thorax. The pile is extremely short 

 and setate and appressed and very little longer on 

 the lateral margin; the first tergite has 4 or 5 short, 

 lateral bristles, none on the remaining tergites. In 

 the male there are six tergites. Females with six ter- 

 gites, the seventh and eighth tergites in the female 

 completely concealed beneath the sixth. Male termi- 

 nalia partly rotate, rather small and largely concealed 

 beneath the seventh tergite, which in turn is concealed 

 by the sixth tergite. The cavity is small but open 

 along the true ventral aspect. Gonopod with a slen- 

 der, terminal, toothed process. Female terminalia 

 completely concealed from the lateral aspect. 



Distribution: Nearctic: Cerotainiops dbdominalis 

 Brown (1897) [ = mfiventris Curran (1930), similis 

 Brown (1897)], dbdominalis atripes McAtee (1919) ; 

 oma Pritchard (1942); wilcoxi Pritchard (1942). 



Systropalpus, new genus 

 Figures 289, 640, 1242, 1251, 1606, 2075, 2088 



Type of genus : Systropalpus aurivulpes, new species. 



A large fly, related perhaps to Hyperechia Schiner, 

 but separated by the wide, transverse vertex; both the 

 ocellarium and its bristles minute; the proboscis is 

 longer and greatly thinned from a lateral aspect. The 

 dense mystax suggests Dasyllis Loew from which again 

 it is distinct in the character of the vertex and probos- 

 cis. While other genera have the second palpal seg- 

 ment open and excavated, in this fly it is remarkably 

 wide and leaflike. The claws are moderately blunt and 

 the first posterior cell open. Length 15 mm. 



Head, lateral aspect : The head is long. The face is 

 unusually long and very strongly produced especially 

 on the lower half, which juts considerably forward but 

 is rounded anteroventrally; the upper face is very 

 slightly concave just at the point where the lower face 

 begins to extend forward. The occiput is extremely 

 prominent below due to the oblique anterior recession 

 of the eye which begins very close to the top of the eye. 

 Upper half of postocciput with 5 or 6 weak, slender, 

 reddish bristles, lower occiput with considerable pale 

 brownish yellow, almost white pile. The proboscis is 

 directed straight forward ; it is shovellike and strongly 

 flattened dorsoventrally, the base is very strongly swol- 

 len laterally in profile, the immediate apex still more 

 thinned and with a few hairs above and below. The 

 base bears some long, fine pile. The palpus consists of 

 a large, leaflike structure with sharp, medial ridge; 

 the apical portion bears numerous, rather long, reddish 

 golden hairs, the basal segment if present is exceedingly 

 short but its presence is indicated by the fact that this 

 short, arched base to which the leaflike portion is 

 attached is covered with numerous, long, fine yellow 

 hairs. The antenna attached at the upper fifth of the 



