ROBBER FLIES OF THE WORLD 



555 



Palaearctic: Stilpnogaster aemulus Meigen (1820) 

 [ = fasciata Megerle in literature in Meigen, incerta 

 Wiedemann in literature in Me,\g&n, nigricans Macquart 

 (1834),«te6i7wZeller (1840)]. 



Genus Epiklisis Becker 



FlQUEES 784, 1491, 1500 



Epiklisis Becker, Ent. Mitt., vol. 14, p. 133, 1025. Type of 

 genus: Epiklisis pilitarsis Becker, 1925, by monotypy. 



Small, slender, strongly tapered flies. The face is 

 moderately produced, slightly convex and it begins to 

 rise immediately beneath the antenna, or very close 

 to the antenna. Acrostical elements are distinct but 

 short, dorsocentral elements are scarcely differentiated 

 even posteriorly. Tlie first tergite bears a single bristle, 

 the remainder without bristles. The femora and tibiae 

 are slender with reduced bristles. The ovipositor is 

 short and quite strongly compressed. Length 10 to 

 14 mm. 



Head, lateral aspect: The eye posteriorly is nearly 

 plane, except on the lower third, where, together with 

 the occiput, it is strongly and convexly anteroventrally 

 recessive. The face is moderately produced beginning 

 at or near the antenna and distinctly but gently convex. 

 The occiput is prominent and uniformly developed 

 throughout; it beare 4 bristles on each side near the 

 vertex and fine pile in the middle and below. Proboscis 

 of moderate size but comparatively short, extended 

 obliquely downward, very little longer than the face; 

 it is bluntly roimded at the apex, with rather numerous, 

 stiff, bristly hairs above and below ; dorsal ridge absent ; 

 it is tapered gently towards the base equally in dorsal 

 and lateral aspect and bears laterally near the base 2 

 or 3 long, bristly hairs directed outwardly and a few 

 additional hairs ventrolaterally. Palpus slender, long, 

 cylindrical, with a fused trace of the basal segment; 

 the apex has several, long, bristly hairs, the lateral 

 surface and ventral surface with shorter, fine pile. The 

 antenna is attached at the upper third of the head. 

 First segment is slightly longer than the second, both 

 with rather numerous, comparatively stout, long, black 

 bristles and bristly hairs ventrally. 



Head, anterior aspect: The face below the antenna 

 is about a fourth the head width and slightly wider 

 at the epistoma. The face bears only bristles, which 

 begin near the antenna with a short, bare space im- 

 mediately below. Bristles are numerous and weak dor- 

 sally, blackish above and laterally and below with a 

 medial row of 3 pairs of long, stout, pale bristles; 

 submedially, above the epistomal margin, are 2 pairs 

 of similar, stout, pale bristles. Lateral subepistomal 

 margin without bristles. The subepistoma is large, 

 oblique, barely concave, densely pubescent. Front 

 quite short due to the deep excavation of the vertex. 

 The front is nearly vertical, pubescent, with 4 distinct, 

 rather long, slender, black bristles laterally and 3 other 

 bristly hairs dorsally. Ocellarium moderately large. 



low, rounded, with 3 pairs of fine, slender bristles 

 between the ocelli and 2 pairs behind the ocelli. 



Thorax: The mesonotum bears rather stiff, erect, 

 sharp setae. There are acrostical elements present in 

 a double row of short, stiff bristles. Dorsocentral 

 bristles are poorly differentiated but there are 3 or 4 

 pairs of rather short, slender, posterior bristles; an- 

 teriorly they are not differentiated fi'om the short 

 bristly pile. The notopleuron has 2 moderately long, 

 exceedingly stout, black bristles. Supraalar and posta- 

 lar each with a single exceptionally long and unusually 

 stout, black bristle. Mesopleuron with about 6 fine, 

 long hairs posteriorly; upper stemopleuron similar. 

 Anterior pronotum with only fine, erect pile; hypo- 

 pleuron with 6 rather long, fine, white hairs; meta- 

 pleuron with a radiating, vertical, single row of mod- 

 erately long, slender bristles and yellowish white hairs ; 

 the lower 5 are bristles. Scutellum only moderately 

 thick but convex, with a distinctly impressed rim, and 

 densely pubescent, with fine, scattered hairs on the disc; 

 the basal crease is complete and deep ; the margin has 

 1 pair of fine, rather short, bristly hairs, quite slender. 

 Lateral metanotum with an abundant patch of fine, 

 long, stiff pile. Posterior half of the lateral meta- 

 stemimi and the ventral metastemum with numerous, 

 fine, long hairs; the latter is wide and chitinized. 

 Postmetacoxal area large, membranous, pubescent ; the 

 posterior basalare bears a few, fine, delicate hairs ven- 

 trally, scarcely noticeable. 



Legs : The hind femur is slender and of nearly uni- 

 form thickness throughout ; it is densely, fine, appressed 

 setate dorsally and laterally with almost no pile ven- 

 trally and bears only a few, fine hairs ventromedially. 

 The medial surface is rather narrowly covered with a 

 dense fringe of pale, bristly pile, moderately long and 

 directed downward. Bristles of the legs are compara- 

 tively few and for the most part weak. The hind 

 femur bears a single, stout, subapical, dorsolateral 

 bristle and 2 lateral bristles at the basal and apical 

 fourth. The hind tibia has a short, stout, dorsolateral 

 bristle quite at tlie base ; a slender, dorsomedial bristle 

 at the middle of the tibia, a stout, dorsolateral at the 

 outer fourth and below a corresponding ventrolateral 

 bristle. The middle femur has a stout, distal, anterior 

 bristle corresponding to the one on the hind femur and 

 with a stout, posteroapical bristle. Venti-al surface 

 basally and posteriorly with 4 or 5 stout, long, slender, 

 yeUow bristles. The middle tibia has long, rather stout, 

 yellow bristles. There is a single dorsal bristle in the 

 middle, a posterior bristle at the basal third, 2 anter- 

 oventral bristles on the outer half and an anterior 

 bristle at the outer third, and 2 posteroventral bristles 

 at the middle and outer fourth. Tlie anterior femur 

 has only 3 long, stout, pale, posteroventral bristles on 

 the basal half. Anterior tibia with 2 short, black pos- 

 terodorsal bristles, black at the basal and outer third; 

 and with 2 quite long, basally stout, attenuate, pale, 

 posteroventral bristles. Claw slender, sharp, curved 

 from the base; pulvilli long but slender; empodiiun 

 from a half to two-thirds as long as the claw. 



