ROBBER FLIES OF THE WORLD 



549 



doi-solateral bristles, and dorsally at the subapex a 

 stout, conspicuous bristle on each side, but none at the 

 apex. Ventral surface of this femur with a moderately 

 dense fringe of pile of medium length, sometimes con- 

 centrated on the outer half. The hind tibia bears a 

 stout, dorsolateral bristle at the base, 1 or 2 at the 

 middle, a dorsomedial bristle near the middle, and at 

 the base often 3 or 4 long, stout, ventral bristles closely 

 set together; it also bears a ventrolateral fringe of 15 

 or more slender bristles or bristly hairs, more or less 

 confined to the basal two-thirds. Middle femur with a 

 conspicuous, anterior bristle at the outer fourth and 1 

 posterodorsally at the apex ; its tibia has 1 bristle dor- 

 sally beyond the middle, or sometimes 2 and generally 

 with no other bristles. Sometimes there is a median 

 posterior bristle. 



Anterior femur with a fringe of exceptionally slender 

 bristles and bristly hairs ventrally. The anterior tibia 

 has a conspicuous row of 4 or 5 dorsal bristles and 1 

 basal anterodorsal element, besides 2 posteroventral 

 bristles. All the basitarsi are stout with stubby, spike- 

 like bristles; the hind basitarsus is long as the next 

 three segments; the anterior basitarsus at least longer 

 than the next two and characteristically and conspicu- 

 ously swollen and stout. Claws stout, sometimes rather 

 blunt at the apex, but generally moderately sharp, pul- 

 villi and empodium well developed. Lateral surfaces 

 of coxae with bristles weak or absent and the posterior 

 trochanters likewise. 



Wings : The wings are often tinted with pale brown 

 or yellowish; the marginal cell is closed with a mod- 

 erately long stalk and is very little widened. The an- 

 terior branch of the third vein ends a little above the 

 wing apex; the posterior branch is strongly sinuous 

 and ends a like distance behind the wing apex. The 

 basal half of this cell is widened, partially occluding 

 the cell behind. The base of the second posterior cell 

 arises obliquely and is much wider than the end of the 

 discal cell. Fourth posterior cell and anal cell each 

 closed with a short stalk. Alula large, the ambient vein 

 complete. 



Abdomen : The abdomen is comparatively robust and 

 of moderate length, longer in females because of the 

 ovipositor. The male abdomen is subcylindrical and 

 distinctly tapered ; in the female the first five segments 

 are apt to be somewhat swollen and more or less oval, 

 strongly tapered on the fifth segment, to which the 

 slender ovipositor is attached. Pile of abdomen dense, 

 coarse and chiefly erect. The pile, narrowly over the 

 medial portion of tergites, tends to be appressed. Bris- 

 tles are restricted to the sides of the first tergite, where 

 they may occur in a cluster of 5 or may be virtually ab- 

 sent, being replaced by dense pile. Males with eight 

 tergites but the eighth extremely short. Male terminalia 

 characteristic; the hypandrium and its conspicuous 

 clasper and the gonopod are all strongly arched down- 

 ward as a imit, and the superior forceps with associated 

 stmctures arched forward and slightly upward, so that 

 a definitive gap or a wide angle tends to lie between 



them. The superior forceps apically emit paralobi 

 which may be conspicuous and the medial proctiger is 

 long, prominent, and erect. The female terminalia con- 

 sist of the last five segments; the sixth, seventh and 

 eighth are exceptionally long and of nearly equal 

 length, the sixth and seventh cylindrical; the eighth 

 and remaining segments are strongly compressed later- 

 ally. Each segment of the ovipositor is progressively 

 more narrow than the next. 



Distribution : Palaearctic : Astochia caspica Hermann 

 (1917) ; completa Becker (1926) ; metatarsata Becker 

 (1913) ;sar'f;?tena Becker (1923) ; sot^aZw Wulp (1899) ; 

 virgatipes Coquillett (1898). 



Oriental: Astochia annulipes Hermann (1917) ; canis 

 Bromley (1935) ; determinatus Walker (1860) ; griseus 

 Wiedemann (1821); inermis Hermann (1917); longi- 

 stylus Wiedemami (1828) [^^latro Doleschall (1857), 

 Uerehratiis Macquart (1838), vertehratus Wulp 

 (1898)]; philus Walker (1849); scalaris Hermann 

 (1917); trichura Hermann (1917); trigemina Becker 

 (1925). See addendum (p. 595) for other synonymy. 



Genua Antiphrisson Loew 

 FiouEES 357, 781, 1531, 1540, 2302, 2344, 2365, 2371 



Antiphrisson Loew, Linnaea Entomologica, vol. 4, p. 124, 1849. 

 Type of genus : Antiphrisson trijarius Loew, 1849. 



Kather less than medium size flies, characterized by 

 the moderately produced face with dense mat of down- 

 wardly directed, weak bristles. The third antenna! 

 segment is rather swollen dorsoventrally and bears a 

 quite short style. Pile abundant but short, appressed 

 and setae. Bristles are prominent on the mesonotum, 

 but more or less reduced elsewhere. Related to Asilus 

 Linne. Length 16 mm. 



Head, lateral aspect: The face is slightly produced 

 on the upper half and is a little more prominent on the 

 lower half but is without a strong facial gibbosity. The 

 eyes are long, strongly recessed below. The occiput is 

 well developed, and extends to the vertex; its pile is 

 moderately abundant on the upper half, with a fine 

 fringe of hairs lying both lateral and medial to the 

 bristles and with long, matted, curled, abundant pile 

 on the lower half of the occiput. Weak bristles begin 

 below the middle of the head and consist of 12 pairs, 

 with at the top of the vertex 4 pairs of additional, stout, 

 short bristles and a tuft of bristles on each side behind 

 the vertex. The proboscis is short, stout, strongly thick- 

 ened toward the base with moderately high dorsal 

 ridge; the apex is obtusely truncate and laterally bears 

 an apical fringe of stiff hairs; base below with long, 

 coarse hairs. Palpus of one segment with stiff, bristly, 

 apical pile. The antenna is attached shortly above the 

 middle of the head, and somewhat shorter than usual. 

 The first segment is a little longer than the second; 

 the second is distally exi^anded. The third segment 

 is as long as the first two segments combined, strongly 

 swollen through the middle and lateral aspect but lat- 

 erally compressed; it bears a short, distinct microseg- 



