ROBBER FLIES OF THE WORLD 



545 



tibiae except on the anterior tibia where the ventral and 

 posteroventral surfaces bear moderately long, stiff 

 hairs. Bristles are numerous and stout, the hind femur 

 bears 5 lateral bristles, 7 ventrolateral, 6 ventral, 4 

 ventromedial and usually 2 or 3 medial bristles near the 

 base ; dorsally at the apex and subapex there is a stout 

 bristle on either side. The hind tibia bears 3 dorso- 

 lateral, 1 of them basal, 1 dorsomedial near the middle, 

 3 or 4 lateral bristles and 4 prominent, ventrolateral 

 bristles; the apex bears 10 bristles. Middle femur with 

 3 anterior bristles, 3 or 4 anteroventral bristles, and 12 

 to 15 ventral bristles, besides 2 prominent, posterodor- 

 sal elements at the apex and 1 opposite on the anterior 

 side. The middle tibia bears 4 anterodorsal, 3 antero- 

 ventral, 3 posterodorsal, 4 posterior and 2 or 3 postero- 

 ventral bristles. The anterior femur bears in the 

 genotype a conspicuous posterodorsal row of 6 stout 

 bristles and a ventral row of 6 or 7 bristles, besides other 

 shorter ones. The anterior tibia is rather similar to the 

 middle pair with 4 stout, anterodorsal bristles on the 

 basal third, 8 or 9 short posterodorsal bristles and 3 con- 

 spicuous, long, posteroventral bristles. Anterior basi- 

 tarsus longer than the next 2 segments, the hind basitar- 

 sus as long as the next 3 segments. Claws stout, sharp, 

 strongly bent at the apex ; the pulvilli large, the em- 

 podimn bladelike. 



Wings: The wings are often tinged with yellow or 

 brown; the anterior branch of the third vein ends 

 shortly before the wing apex, the posterior branch 

 shortly behind. The base of the second submarginal 

 cell is widened both above and below the third vein; 

 the base of the second posterior cell is abruptly widened 

 and at least twice as wide as the end of the discal cell. 

 Posterior crossvein much longer than the end of the 

 discal cell. Fourth posterior cell closed with a rather 

 long stalk. Alula large, the ambient vein complete. 



Abdomen : The abdomen is stout and elongate, rather 

 strongly tapered in both sexes from the end of the 

 fourth segment. Bristles are restricted to the sides of 

 the first tergite with sometimes a patch, as in the type 

 of genus, in the middle of the lateral margin of the 

 second segment but none on remaining segments. Pile 

 moderately abundant, fine, subappressed and setate but 

 with long, coarse pile laterally on the first and some- 

 times the second segment and sometimes shorter bristly 

 pile laterally on the third segment. Sternites with a 

 few scattered, stiff hairs on the first 3 or 4, and setae 

 beyond. Males with seven tergites and a trace of the 

 eighth only laterally. Females with seven segments 

 not incorporated in the ovipositor. The male termin- 

 alia comparatively small; with only moderately long 

 superior forceps, broad at base, slightly narrowed and 

 bluntly rounded apically and directed somewhat 

 obliquely upward. The gonopod is about two-thirds 

 as long and also turned upward. Proctiger protruding 

 and erect. The hypandrium is well developed and 

 transverse apically. Claspers elongate; cavity widely 

 open below. Aedeagus with three fine prongs. The 

 female ovipositor consists of the conical, subcylindroid 



eighth segment which is as long as the seventh segment, 

 with stiff, sharp, erect, lateral and dorsal bristles and 

 of the shorter, much smaller, ninth and tenth segments, 

 which are also much more narrow. Tenth segment free. 



While this genus taken in the wide sense is exception- 

 ally large and, as presently understood, world wide in 

 distribution, there are comparatively few species that 

 fall into Asilus in the strict sense and these are much 

 more limited in distribution. A few are found in North 

 America ; the type of genus and several others are from 

 Europe. There remains a large assemblage of older 

 species known only from the types ; these have not been 

 restudied critically and we do not know where they be- 

 long ; until such time as they are re-examined they must 

 be listed m\A^v Asilus. 



Distribution: Nearctic: Asilus autumnalis Banks 

 (1914) ; blanfoni Bromley (1940) ; calif ornicus Hine 

 (1909) ; citm Hine (1918) ; compositus Hine (1918) ; 

 delicatulus Hine (1918) ; fattigi Bromley (1940) ; for- 

 mosus Hine (1918) ; floridensis Bromley (1940) ; frosti 

 Bromley (1950) ; fulviventris Schaeffer (1916) ; gil- 

 vipes Hine (1918) ; hubhelli Bromley (1950) ; hypopy- 

 gialis Schaeffer (1916); knulli Bromley (1940); per- 

 similis Banks (1920) ; platyceras Hine (1922) ; sackeni 

 Banks (1920) ; schuhi Bromley (1940) ; sericeus Say 

 (1823) [ = herminius Walker (1855)]; vescus Hine 

 (1918). 



Neotropical: Asilus alhipilosus Macquart (1846); 

 antiphus Walker (1849) ; apicalis Bellardi (1861) ; 

 aureomaculatus Bromley (1932); haletus Walker 

 (1849) ; harhiventris Rondani (1850) ; hrachypterus 

 Philippi (1865) ; iromleyanus Carrera and d'Aiidretta 

 (1950) ; hullatus Bromley (1929) ; calatinus Walker 

 (1849); chrysauges Osten Sacken (1887); clavatus 

 Macquart (1838); coeruleiventris Macquart (1846); 

 colomhiae Macquart (1838) ; concepcionensis Bromley 

 (1932) ; consanguineus Macquart (1846) ; crassus 

 Bromley (1932) ; cuyanus Lynch Arribalzaga (1880) ; 

 eritrichus Philippi (1865) ; gammaxus Walker (1851) ; 

 gaviusWs^kQv (1851) ; gcewn Walker (1849) ; gertschi 

 Bromley (1951) ; hehes Walker (1855) ; helix Bromley 

 (1985); herdonius Walker (1851); fheydenii Wiede- 

 mann (1828) ; imitator Lynch Arribalzaga (1883) ; in- 

 amntusl^SiikRY (1860) [ — inauratus AXAvich. (1905)]; 

 incomptus VhWip^i (1865) ; m/wsmfws Bellardi (1861) ; 

 Ze6asM Macquart (1838) ; Zeom'</es Walker (1851) ; loewi 

 Bromley (1929) ; longiusculus'W^i&.^v (1855) ; luctuosus 

 Macquart (1838) ; lutipes Wiedemann (1828) ; lycorius 

 Walker (1851) ; mayi Bromley (1932) ; megacephalus 

 Bellardi (1861); megastylus Philippi (1865); fmel- 

 anacrus Wiedemann (1828); tnellipes Wiedemann 

 (1828) ; mea»canM5 Macquart (1846) ; 7nodellus'Bvova\&j 

 (1932) ; mydas Brauer (1885) ; neriacensis Bromley 

 (1951) ; nigrinus Macquart (1848) ; occidental^ Phi- 

 lippi (1865) ; pamponeroides Bromley (1932) ; perrum- 

 ^pens Walker (1860) ; pe^e'cws Walker (1849) ; poecilopus 

 Philippi (1865); ramsdeni Bromley (1929); sericans 

 Walker (1857) ; serwz7?€e Macquart (1834) ; sexmacula- 

 tus Walker (1855) ; tatius Walker (1851) ; tenuiventris 



