ROBBER FLIES OF THE WORLD 



465 



lateral distal bristle. All the tarsal segments are rather 

 shortened ; the basitarsus is rather robust. Pile of the 

 legs dense, especially on the first 4 tibiae, which lack 

 bristles. Claws moderately sharp at the apex, the pul- 

 villi and empodium long. 



Wings: The wings are comparatively broad and ex- 

 tend to the apex of the terminalia ; the venation is like 

 Promachus Loew; anal lobe is moderately extended 

 distally. The ambient vein is evanescent on the anal 

 lobe. 



Abdomen : The abdomen is short and robust, mostly 

 pale pollinose with dark, dorsal basal bands and rather 

 long, dense, appressed pile on the fourth to seventh seg- 

 ments and still longer, erect, shaggy jDile on the sides of 

 the basal segments. The first tergite is without bristles 

 or has only very weak elements. Male terminalia typi- 

 cal for Promachus but shorter. Aedeagus exceptionally 

 long, extending well beyond the forceps and with three 

 tubular prongs. Female with short ovipositor moder- 

 ately compressed laterally; the eighth segment is dis- 

 tinctly longer than the remaining two, which are 

 compressed to a similar extent. Only one species is 

 known in Parapromachus. 



Subgenus Philomachus Karsch 



Figures 374, 381, 733, 1441, 1450 



Philomachus Karseh, Berliner Ent. Zeitschr., vol. 31, p. 375, 

 1887. Type of subgenus : Asilus vagator Wiedemann, 1828, 

 83 Philomachus rhopalocerus Karsch, 1887, by monotypy. 



Flies of medium size or larger with three submarginal 

 cells, the venation like that of Promaclius Loew, to 

 which they are closely related. They are recognizable 

 by the straight face and wide lamella at the end of the 

 antennal style, which is more likely to be conspicuous 

 in the males. They are dark colored, pollinose flies 

 with rather long pile on the thorax, head and legs, the 

 base of the abdomen and sternites. Wings long and 

 slender. Abdomen strongly tapered. Length 17 to 20 

 mm. 



Head, lateral aspect: The face is moderately pro- 

 duced but plane and more conspicuous below. Occiput 

 imusually thick but most prominent medially and slop- 

 ing gently outward to the eye margin ; pile quite dense 

 and unusually long and fine, continued dense medially 

 on the dorsal half with bristles beginning above the 

 middle of the head ; the first 3 bristles are turned down- 

 ward and there are 7 longer, quite stout, slightly curved 

 dorsal bristles. Proboscis stout and rather long, and 

 cylindrical apically, strongly swollen toward the base 

 from the dorsal aspect. Palpus elongate, large, cylin- 

 drical, with numerous, long, bristly hairs and apical 

 bristles. The antenna is attached a little below the 

 upper third of the head, of only moderate length but 

 slender; the firet segment is slightly more than twice 

 as long as the second. The third segment is attenuate 

 distally to about one-third its maximum width, it is a 

 little longer than the first segment, without microseg- 

 ment and the style is ly^ times as long as the third seg- 



535914— 62— pt. 2 4 



ment and bears a wide, spatulate, flat lamella at the 

 apex beyond which is a bristly spine. 



Head, anterior aspect: The face below the antemia 

 is less than a third the head width and slightly widened 

 at the epistoma. Face densely pubescent, with con- 

 siderable long, bristly pile on the dorsal half and 2 

 or 3 long, stout bristles medially below the middle of 

 the face and also with a row of 7 pairs extending across 

 the epistoma in front. Down the upper half of the 

 lateral subepistomal margin are additional bristles. 

 Front pollinose, with an irregular, lateral row of 12 

 long, slender, black bristles and a patch of pale pile in 

 front of each antenna. Vertex deeply excavated, but 

 with oblique sides; the ocellarium is quite small, low 

 and elongate with small ocelli and bearing 2 or 3 pairs 

 of slender hairs between the posterior ocelli and several 

 additional hairs behind the ocelli. 



Thorax: The whole thorax is pollinose; pile of 

 mesonotum moderately abundant, rather long and 

 bristly. There is a double irregular row of acrostical 

 elements anteriorly merging into the single row behind 

 the humerus. Dorsocentral elements are poorly dif- 

 ferentiated anteriorly but become long and strong be- 

 hind the suture where there are at least 4 such elements. 

 Humerus densely long, bristly pilose. The excep- 

 tionally stout, long, lateral bristles consist of 2 noto- 

 pleural, 1 supraalar, 1 suprapostalar, 2 postalar, and 

 the scutellar margin has 6 pairs of long, slender 

 bristles ; the middle of the disc bears 4 pairs of equally 

 long, perhaps stouter, black bristles. Mesonotal bristles 

 black, the posterior scutellar bristles pale. Scutellum 

 thick, convex with impressed rim and with considerable, 

 fine, long, discal pile. Propleuron everywhere densely 

 long, fine pilose ; only the pi'onotum with bristles, con- 

 sisting of 2 or 3 pairs of slender elements ; the fine, long, 

 dense pile is continued anteriorly over the whole an- 

 terior coxa with bristles entirely absent. A tuft of long, 

 fine, dense pile present dorsally and posteriorly on the 

 mesopleuron, anteriorly and middorsally on the sterno- 

 pleuron, on the pteropleuron, and a wide band of some- 

 what stiffer pile on the posthypopleuron. Metapleuron 

 with a vertical band of long, slender, bristly hairs. 

 Lateral slopes of the metanotum micropubescent only; 

 postmetacoxal area membranous; tegula with minute, 

 short setae; posterior basalare with a tuft of 5 or 6 

 stiff or bristly hairs. 



Legs : The femora are all short and stout and a little 

 swollen. The anterior 4 femora are distinctly more 

 swollen than the hind pair. Dorsal and anterior pile 

 of the hind femur fuie, short and appressed. The hind 

 femur has stout bristles, 4 ventrolateral beginning at 

 the basal third; at the subapex 3 exceptionally long 

 bristles and at the apex 2 medial bristles; also 2 long, 

 ventral, basal bristles and a fringe of fine, long hairs 

 dorsally, medially and ventrally. Hind tibia with 2 

 dorsomedial bristles on the basal half, 1 dorsolateral at 

 the base, 1 ventrolateral, 2 long, stout, lateral bristles 

 near the middle and 2 ventral bristles. Middle femur 

 with an anterior bristle near the base, a stout bristle 

 at the outer fourth, another near the apex postero- 



