LEFTOGASTRINAE 



ROBBER FLIES OF THE WORLD 



307 



Text-Figure 20. — Oph.ionom.ima solocifemur Enderlein. 



as long as the third and attenuate at apex. First 

 segment with 2 or 3 minute setae ventrally and dor- 

 sally, the second with 2 or 3 moderately long, quite 

 stout setae or short bristles ventrally and dorsally at 

 the apex. 



Head, anterior aspect : The face below the antenna is 

 a tenth the head width and divergent below to a sixth 

 of head width across the epistoma and to a third at the 

 base of the proboscis. The proboscis is directed 

 horizontally forward or upward. The head is not ex- 

 tended below the eyes; the eyes are rather lower than 

 the cheeks; subepistomal area small, concave and 

 oblique and bare. The face is micropubescent with a 

 row of 3 or 4 fine, bristly hairs across the face above the 

 margin of the epistoma. Pile absent. Front short, 

 narrow, pubescent without pile or bristles, vertex not 

 excavated except posterior to the ocelli where there is a 

 very deep pocket with vertical sides. The dorsal pos- 

 teromedial margin of the eyes is strongly rounded and 

 convex. Ocellarium low, without pile or bristles. An- 

 terior eye facets strongly enlarged. 



Thorax : The thorax is densely fine, short, appressed 

 pubescent on the pleuron and the sides of the meso- 

 notum and posteriorly on the mesonotum. The meso- 

 notum is rather abrupt, but convex anteriorly, only a 



little more strongly sloping posteriorly. Pile of the 

 mesonotum very nearly reduced to none; there are 1 

 or 2 fine hairs along the lateral portions of the suture, 

 a few scattered, minute, acrostical elements anteriorly, 

 and anteriorly a few, fine, dorsocentral elements which 

 on the posterior half of the mesonotum become a little 

 longer and stouter and form an irregular multiple row 

 on either side opposite postalar area. Humerus with 

 a few, short hairs anteriorly. The following comple- 

 ment of very long and exceptionally stout bristles is 

 present : 1 notopleural, 1 postsupraalar, but no postalar 

 or scutellar bristles; both these latter areas have some 

 quite short, stiff, marginal pile. Scutellum flattened 

 with nearly rectangular rim, the surface pubescent, the 

 basal crease shallow medially, otherwise without pile. 

 Propleuron with a few scattered hairs ventrally, the 

 anterior sternopleuron with 5 or 6 long, slender, bristly 

 hairs, the pleuron otherwise pubescent only except on 

 the metapleuron where there are a few moderately long, 

 stiff hairs. Lateral slopes of the metanotum pubescent 

 only, lateral metasternum quite elongate, extended 

 backward and upward with its ventral margin some- 

 what rolled but leaving the medial third of the ventral 

 aspect and the ventral metasternum as well as the post- 



