«. 

 AET. 7 AMEEIOAN" MUSCOID FLIES IN" VIENNA MUSEUM ALDEICH 25 



PAMMAERUS LEPTOTRICHOPUS, Braoer and Bergenstamm 



Male. — ^Front broad, 0.35 of the head width, with two large orbital 

 bristles on each side. The ground color of the front is black, heavily 

 overlaid with yellow poUen. The median stripe is brown, almost as 

 wide as either parafrontal. Verticals one large and one small; 

 frontals about six, the upper two pairs represented only by large 

 scars, probably reclinate, the next ones much smaller, decussate, one 

 pair large just at the root of the antennae, and one pair below these. 

 The parafrontals are rather densely covered with short black hairs, 

 which below the upper orbital are proclinate, but above it are recli- 

 nate, while near the median stripe they are directed toward the mid- 

 dle line. This peculiar arrangement of hairs I have never seen in 

 any other species, and it is rather noticeable. Parafacial and poste* 

 rior orbit, except the upper part, bright silvery pollinose ; the former 

 gradually narrowing to almost the level of the vibrissae, where it is 

 about as wide as the third antennal joint. Antennae black, rather 

 brownish at base; third joint decidedly slender and about three and 

 one-half times as long as the second. Arista bare, very thin on the 

 apical half, the basal third slightly thickened. Facial ridges with 

 hairs and small bristles extending more than one-third of the way 

 to the root of the antenna. Cheek one-sixth the eye height; palpi 

 yellow; proboscis small; back of head flat with usual ruff of white 

 hairs not very well developed, the lower part of the head having 

 many black hairs extending from the cheek half-way up the orbit. 

 Ocellar bristles small, proclinate. 



Thorax and abdomen wholly black in ground color, the former 

 with four subshining black stripes on gray pollen. The scutellum 

 with yellowish pollen, black at base and a very slight reddish tinge 

 in the ground color around the apex. Thoracic chaetotaxy : acrosti- 

 chal, 3, 3; dorsocentral, 3, 4; humeral, 4; posthumeral, 3 (including 

 one interhumeral) ; presutural, 2; notopleural, 2; supraalar, 3; intra- 

 alar, 3; postalar, 2; sternopleural, 2, 1; pteropleural, 0; scutellum 

 with 3 lateral and a small decussate pair of apicals. 



Abdomen broadly pollinose on the last three segments, but not in 

 very good condition to describe; the first segment has a very small 

 pair of median marginals ; the second a large pair ; the third a mar- 

 ginal row of eight; the fourth a smaller marginal row of the same 

 number. There are no discals on any segment; the fourth segment 

 is densely pollinose on its whole upper surface as far as the row of 

 bristles. Genitalia small; legs black; the knees narrowly reddish; 

 all the claws and pulvilli small; middle tibia with one large bristle 

 on outer front side; hind tibia with an even row of cilia and one 

 larger bristle near the middle. 



