ROBBER FLIES OF THE WORLD 



559 



In the type of genus the hind femur bears bristles, most- 

 ly long and stout, which consist of 4 dorsolateral, the 

 latter matched by a similar, subapical dorsomedial 

 bristle and with 1 apical dorsomedial bristle; there may 

 be 2 or 3 lateral bristles present beyond the middle and 

 also 8 ventrolateral bristles. The hind tibia bears 2 

 dorsomedial bristles near the middle, 3 dorsolateral 

 bristles, and 3 ventrolateral bristles beginning at the 

 middle and beyond. Middle femur with on the outer 

 half 3 anterodorsal and 3 posterodorsal bristles, and 5 

 prominent anteroventral bristles, besides an abundant, 

 ventral fringe of fine, long pile on both sides. Middle 

 tibia with the bristles quite fine; there are 2 anterior 

 on the outer half, 3 dorsal, distributed along the middle, 

 1 postero ventral and 1 anteroventral on the outer 

 fourth, besides long, fine pile anteriorly, posteriorly, 

 and ventrally. 



Anterior femur without bristles, but with a conspicu- 

 ous, dense, ventral fringe of long, fine pile and postero- 

 dorsally a fringe of delicate, bristly hairs; this tibia 

 has a single, anterodorsal bristle at the base, 3 postero- 

 dorsal bristles from near the middle and beyond, and 

 moderately long, fine pile ventrally. All the basitarsi 

 relatively short; first four as long as the next two seg- 

 ments or slightly longer. Hind basitarsus as long as 

 the next three. Intermediate tarsal segments quite 

 short; tarsi end in slender, sharp claws, strongly bent 

 apically long pulvilli, basally stout empodium; the first 

 pair is tliree-fourths as long as the claw, the last pair 

 only half as long. 



Wings : The marginal cell closed with a short stalk, 

 subcostal cell quite narrow, the marginal cell wider. 

 The anterior branch of the third vein is strongly sinu- 

 ous ; second submarginal cell broad at the base, strongly 

 but gently arched anterobasally, the cell is narrowed in 

 the middle but scarcely wider apically than across the 

 base, and arises a considerable distance beyond the 

 end of the discal cell ; anterior branch of third vein ends 

 before the wing apex, posterior branch only a little 

 farther belund. Posterior cells open widely, except the 

 fourth, which is closed with a moderately long stalk. 

 Apical side of fourth posterior cell straight but an- 

 teriorly rather convex; anal cell closed with a long 

 stalk, concave posteriorly ; the second basal cell ends in 

 two veins, anterior crossvein enters the discal cell be- 

 yond the middle ; alula large, ambient vein complete. 



Abdomen: In the males the abdomen is distinctly 

 shorter than the wing ; the first tergite is only as wide 

 as the mesonotum, its sides protuberant but not anteri- 

 orly demarcated. Male abdomen imusually robust, 

 cylindroid or slightly compressed laterally. Pile of 

 abdomen scanty, short dorsally becoming longer im- 

 mediately towards the sides, fine and more or less erect, 

 except along the middle posteriorly, where it tends to 

 be appressed. Sides of first tergite with 4 pairs of 

 slender bristles. In males the second and third tergites 

 posterolaterally bear at least 3 or 4 quite long, slender, 

 distinct bristles ; females similar, the bristly hairs con- 



tinued on to the seventh tergite. Apical margin of the 

 first tergite in the male with a long posterior fringe of 

 bristly hairs; sternites with long, bristly pile; first 

 sternite with scanty pile. Males with eight tergites, the 

 eighth longer laterally where it is from a fourth to half 

 as long as the seventh tergite and shorter dorsally. All 

 the last four tergites are progressively shortened, the 

 third, fourth, and fifth approximately equal in length. 

 Females with seven tergites, those beyond incorporated 

 in the ovipositor. Male tenninalia exceptionally large, 

 the superior forceps club-shaped, with a posteromedial 

 blunt process; gonopod shorter. Postmargin of the 

 last sternite with a fringe of long, red bristles; hypan- 

 drium apparently wanting; the whole terminalia not 

 rotate. Female terminalia quite flat appressed, paper- 

 thin, and attenuate from the lateral aspect, the eighth 

 tergite is longer than the preceding three tergites. 

 Ninth and tenth tergites short. 



I am indebted to Mr. H. Oldroyd for calling to my 

 attention the confusion M'hich has long existed with re- 

 spect to the European robber flies, which have been cur- 

 rently placed under the name Protophanes Loew, and 

 the great assembly of entirely New World species placed 

 in the past under the name Erax Scopoli. In 1910, 

 Coquillett designated Erax harhatus as the type of 

 genus of Erax. This was the fifth species. These Pa- 

 laearctic flies only superficially resemble the widespread 

 New World genus, which must now be assigned another 

 name. This New World group of flies now becomes 

 assigned to Nerax, new genus. The species Protophanes 

 punctatus, an Old World species and the type of genus 

 of Protophanes Loew, has generally been considered 

 a synonym of Erax harhatus; the latter does have pri- 

 ority. In any case the name Erax Scopoli camiot be 

 used for the New World group and it seems entirely 

 proper to begin using Scopoli's name for the Palaearctic 

 species, which have previously gone under the name 

 Protophanes ; I have, therefore, placed Protophanes 

 in synonymy. I call attention to the scattered distribu- 

 tion of some species placed by Kertesz in this group 

 {Protophanes Loew) ; I consider it highly doubtful that 

 all of these species are congeneric with the European 

 Erax iarbatus Scopoli {Protophanes punctatus Meigen 

 of authors) . 



Distribution : Palaearctic : Erax atticus Loew (1871) ; 

 hartatus Scopoli (1763); crassicauda Loew (1862); 

 curiatms Walker (1849) ; fuscidus Pallas in Wiede- 

 mann (1818) ; nubecula I^oew (1848) ; punctatus Mei- 

 gen (1804) [=?frontalis Olivier (1789); punctipennis 

 Meigen (1820)]; sinensis Macquart (1838); tenuicor- 

 nis Loew (1848); vaiians Meigen (1830) [=variu,s 

 Loew (1848)]. 



Ethiopian: Erax alhiceps Macquart (1849) ; costalis 

 Wulp (1899) ; nigrotinctus Becker (1909). 



Oriental: Erax integer Macquart (1846) ; ochrivent- 

 m Becker (1923). 



AnstvaXivin: Erax alMventris Macquart (1849) ; plan- 

 taris Thomson (1869) ; Salomon Macquart (1838). 



