DASYPOGONINAE 



ROBBER FLIES OF THE WORLD 



219 



fourth, the epandrium cleft but the sides overlapping; 

 the hypandrium is broad, long and extensive, the gono- 

 pod conspicuous, laterally convex, and with terminal 

 appendage or process. Genital cavity small but ex- 

 posed. Female terminalia with acanthophorites and 

 5 pairs of large, blunt, spoonlike spines. Eighth 

 sternite with medial cleft and ventrally depressed. 



Distribution: Nearctic: Plesiomma unicolor Loew 

 (1866). 



Neotropical: Plesiomma angusta Macquart (1848); 

 atrum Bromley (1929) ; caedens Wiedemann (1828) ; 

 caminarium Wiedemann (1828) ; ferruginea Macquart 

 (1838) ; fuliginosus Wiedemann (1821) ; funestum 

 Loew (1861) \_ = lugubre Jaennicke (1867)]; haemor- 

 rhoum Fabricius (1805) ; indecorum Loew (1866) 

 [=longiventre Schiner (1867)]; inflatus, new species; 

 jungens Schiner (1867); leptogastrum Loew (1866); 

 lineatwm Fabricius (1781) [=macrvm Loew (1866)]; 

 salti Bromley (1929) ; semirufum Wiedemann (1828) ; 

 sepia, new species; testaceum Fabricius (1805). 



Country unknown: Plesiomma testaceum Macquart 

 (1838). 



Boropis, new subgenus 



Type of subgenus : Asilus lineatwm Fabricius (1781) . 

 For those species with no spines on the scutellum 

 the name Boropis, new subgenus is proposed. 



Dapsilochaetus, new subgenus 



Type of subgenus: Dapsilochaetus inflatus, new 

 species. 



Related to Plesiomma Macquart. These flies are 

 distinguished by the swollen antennal segments and the 

 presence of numerous, very stout bristles on the whole 

 lower half of the face. Mesonotum with well developed 

 acrostical bristles and long, slender, dorsocentral 

 bristles, which extend nearly to the humerus. Scutel- 

 lum with 3 pairs of bristles. Length 17 mm. 



Head, lateral aspect : The head is of medium length, 

 face rather prominent, slightly more extensive below but 

 of very little height. The cheeks are undeveloped but 

 the subepistoma is quite large, and oblique, and extends 

 well below the eye. Occiput rather prominent sub- 

 laterally with coarse pile ventrally and weak bristles 

 dorsally. Proboscis quite broad on the basal two-thirds 

 from the dorsal aspect so that the whole is rather de- 

 pressed dorsoventrally. Laterally the base is swollen 

 below and the apex bears numerous, stiff hairs and is 

 longitudinally striate laterally. Palpus unusually ro- 

 bust and stout on both segments, which are of equal 

 length, the first segment is not excavated, both are bar- 

 rel-shaped and bear numerous, long, bristly hairs; none 

 at the apex on the second segment. The antenna is at- 

 tached a little above the middle of the head, the first 

 segment is exceptionally stout and inflated, a little 

 longer than wide and of nearly the same length as the 

 second segment, which is not as thick. The first seg- 

 ment is densely covered with moderately long, slender 

 bristles and bristly hairs on the dorsal and dorsomedial 



surfaces, with equally numerous, similar but longer 

 hairs and bristles on the whole lateral and ventral 

 surfaces. Second segment similar but with the hairs 

 and bristles shorter. The third segment is short and 

 broad from lateral aspect, especially in the middle; it 

 is a little narrowed at base and apex; it bears 6 or 7 

 rather long, dorsal bristles extending beyond the apex. 

 At the apex it has a short microsegment followed by 

 another which is stout, three times as long as the first 

 microsegment and directed obliquely downward and has 

 a minute, apical spine. 



Head, anterior aspect : The head is quite similar to 

 that of Plesiomma and has deep, ventrolateral pockets 

 below and along the eye margin. Face pubescent, the 

 upper half without pile, the lower half with several 

 rows of closely set, stout, moderately long, curved, red- 

 dish bristles. Front with a few setae scattered through 

 the middle. Vertex with 3 pairs of prominent bristles 

 between the ocelli, 2 pairs of long, bristly hairs anteri- 

 orly, and 2 or 3 pairs of equally stout, long, reddish 

 bristles behind the ocelli. 



Thorax : The thorax is similar to that of Plesiomma. 

 Mesonotum with pollen, and an acrostical row of slen- 

 der bristles and somewhat more prominent, long, but 

 slender, dorsocentral bristles which begin behind the 

 humerus. Mesonotuni medial to the humerus and lat- 

 erally with a number of long, coarse hairs. Lateral 

 bristles stout. There are 3 notopleural, 1 supraalar, 1 on 

 the postalar callosity, and 3 pairs on the scutellum. 

 Humerus with several slender bristles anteriorly and 

 other bristly hairs. Postmetacoxal area membranous; 

 presternum dissociated. 



Legs : The legs are similar to those of Plesiomma. 



Wings : The wings are similar to Plesiomma. Pos- 

 terior crossvein short, marginal cell open by nearly its 

 maximal width, rather dark sepia in color. 



Abdomen: The abdomen is elongate and quite sim- 

 ilar to that of Plesiomma. 



Dapsilochaetus inflatus, new species 



Length 16 mm. Male. Head: Vertex and occiput 

 black, the upper sides of the face reddish brown and 

 densely covered with reddish brown micropubescence. 

 The middle of the face and the ventral part are blackish 

 and covered with a dark, micropubescence. Cheeks be- 

 low eyes and the ventral part of occiput are rather light, 

 reddish brown. Palpus composed distinctly of two seg- 

 ments, rather light brownish yellow, with a blackish 

 spot dorsally at the apex of the last segment; the second 

 segment is attached to the first a little to one side of the 

 apex; both segments bear numerous, stiff, long, reddish 

 yellow hairs. Proboscis black with the base ventrally 

 becoming light reddish brown and this part bears some 

 long, reddish hairs. Occiput bears a submarginal band 

 of moderately stiff, bright, reddish, bristly hairs, which 

 become a little more conspicuous and stout dorsally. 

 Ocellarium with 6 pairs of conspicuous, moderately 

 long, reddish bristles. 



Antenna at least as long as the head and unusually 

 stout with the first segment rather swollen and inflated. 



