ROBBER FLIES OF THE WORLD 



595 



and 3 at the apex, 2 being posterior. Anterior femur 

 with a pair of subapical, dorsal bristles, 1 at the apex 

 on each side and 4 ventral bristles on the basal half. 

 Anterior and midcoxal frontal bristles numerous. 

 Hind tibia with a stout, prominent, dorsomedial bristle 

 near the middle, a dorsolateral at the base, 2 lateral 

 bristles along the middle, and below them 2 ventrolat- 

 eral bristles. Apex with 7 bristles. Anterior 4 tibiae 

 similar ; the posteroventral bristles of each are consid- 

 erably longer and attenuate. Claws slender, sharp, the 

 pulvilli and empodium long. 



Wings : The wings are rather short and broad ; the 

 third vein forks before the posterior cross vein or op- 

 posite; the fourth posterior cell is closed with a long 

 stalk. The anal cell is closed in the margin, or with 

 a short stalk. The alula large, triangular, the ambient 

 vein complete. The second submarginal cell is widened 

 above and below its origin. Nearly the whole wing is 

 villose. 



Abdomen : The abdomen is comparatively short and 

 robust ; the second tergite at base is nearly as wide as 

 the mesonotum. Sides of first tergite with 6 pairs of 

 bristles; pile of abdomen scanty, fine appressed and 

 setate, not longer on the sides. The postlateral margin 

 of the second and remaining tergites have very slightly 

 lengthened setae ; surface poUinose. Seven tergites are 

 visible above in the male, a trace of the eighth visible 

 laterally. Female with seven tergites before the ovi- 

 positor. Male terminalia of moderate size, with long, 

 superior forceps which converge and overlap at apex 

 and long, erect, dorsal proctiger. The gonopod is two- 



thirds as long as the forceps ; the hypandrium is large, 

 broad, the eighth sternite short and transverse; tiie 

 aedeagus has three prongs. The whole ventral cavity 

 of the terminalia is exposed. Female with a small, coni- 

 cal and cylindrical ovipositor; the eighth segment is 

 about as long as the preceding seventh or a little longer ; 

 the ninth is laterally compressed and half as long as 

 the preceding; the terminal proctiger bears fine pile, 

 is not quite as long as the ninth. 



Distribution: Nearctic: Negasihts belli Curran 

 (1934). 



Genus Ni^asilus Hone 



FiGUBES 2531, 2533 



Nigrasilus Hine, Canadian Ent., voL 40, p. 203, 1908. Type of 

 genua: Nigrasilus nitidifacies Hine, 1908, by original desig- 

 nation. 



I give below Hine's description : 



Front and face of ordinary width, face widest below. Facial 

 gibbosity rather prominent and with numerous bristles. Third 

 segment of the antenna rather narrow, and a little longer than 

 the first two together, arista only about half as long as its 

 segment. Thorax with bristles on the posterior part and several 

 bristles on the margin of the scutellum. Wing venation as in 

 Asilus in the restricted sense. Posterior margins of the abdomi- 

 nal segments without bristles that differ in length from those 

 on other parts of the abdomen. Female genitalia plainly coni- 

 cal ; male appendages plainly bent upward near the middle of 

 the length. 



Distribution: Nearctic: Nigrasilus nitidifacies Hine 

 (1908). 



Addendum 



The present work was completed in August 1957, 

 but I have added those genera, by various authors, that 

 have appeared since that time and have come to my 

 notice. Here I take note below of additional synonymy, 

 not previously mentioned in the text, and add three 

 genera. Finally, I include a diagram expressing the 

 relationships and comparative development of the 

 Asilids by tribe and subfamily. 



New synonymy 



Blasdale (1957) in a commendable paper on the 

 Philodictis species of Sudan and South Africa describes 

 several new species and establishes a number of new 

 synonyms drawn from several genera related to and 

 hitherto confused at times with Philodicus Loew. 

 Blasdale's new species are: Philodicus alcimoides, for 

 fratemus Curran, not Wiedemann ; fallidus, vlrolensis, 

 palustris, flavipes, roiusius, furunculus ; of these viro- 

 lensis, pahisfris, rohusfus and furunculAis are from the 

 Sudan. The synonjTny that Blasdale proposes is drawn 

 in part from species laitherto inchided under Alcimus 

 and Promachvs, and consequently alters the faunal list 

 for those genera in this work. 



Under synonymy of Philodicus fratemus Wiede- 

 mann, 1819, which Blasdale transfers from Alcimus, he 

 places Alcimus liiribatus Macquart, 1838, and Promxi- 

 chus twrinus Walker, 1849. 



Under synonymy of Philodicus temerarius Walker, 

 1851, which he transfers from PromMchus, he places 

 Philodicus oiscuripes Loew, 1858, Alcimus aefhiopious 

 Bigot, 1891, E had hirgus notatus Bigot, 1891, Philodicus 

 walkeri Eicardo, 1921, and Alcimus hiseriatus Curran, 

 1927. 



Blasdale transfers to Philodicus the species Prom/i- 

 chus fraterculus Walker, 1855, Alcimus doris Cmran, 

 1927, and Alcimus ludens Wiedemann, 1828. 



Eicardo, 1912, places the following Walker species 

 of Promachus in synonymy under Philodicus javanus 

 Wiedemann: conflnis Walter, 1855, goiares Walker, 

 1849, inserens Walker, 1857, sagittifer Walker, 1851, 

 and telifer Walker, 1851. 



Genus Templasilus Peris 



Templasilus Peris, Eos, vol. 33, p. 275, 1957. Type of genus: 

 Asilus bolivari Arias, 1912, by original designation. 



