Baccha nitidithorax Curran, 1929:9

Black, the antennae and legs in part reddish; wings pale brownish, hyaline on basal third. Length, 9 mm.

Male

Face, cheeks and occiput steel-blue, grayish pollinose; white pilose; upper third of occiput, frontal and vertical triangles, blue-black; tacial tubercle bare apically. Eyes touching for a distance equal to two-thirds the length of the frontal triangle, which is gently swollen on the lower two-thirds and bears a small gray pol- linose spot above; ocellar triangle small, occupying less than the anterior half of the vertical triangle. Anterior oral margin less prominent than the antennal base, the tubercle large and prominent; lower edge of mouth strongly oblique, slightly convex in profile. Antennae brownish red, the third segment short oval.

Mesonotum and a fascia on the pleura beneath the wings shining black, the mesonotum somewhat bronzed, scarcely dulled on the disc; pile brown, rather short; on the pleura and scutellum yellowish. Pleura grayish pollinose; sides of mesonotum in front of the suture mneous; ventral scutellar fringe cinereous.

Legs black; apices of the femora and of the anterior four tibiie, basal half of anterior four tibie, basal fourth of the posterior pair and the first segment of all the tarsi, reddish yellow, the tarsi pale yellowish-brown. Hair black; on the anterior four tibie and the first segment of all the tarsi, yellow.

Wings pale brown, hyaline on basal fourth; stigma brownish luteous. Alula large. Squamae and fringe brown; halteres pale yellow.

Abdomen shining metallic black, slightly bronzed, the apical fourth of the second, half of the third and a broad band across the middle of the fourth segment, opaque. Pile on the first segment, basal half of third and on large triangles on the base of the fourth, white, elsewhere black; appressed on the dorsum.

Genitalia small, blue-black. Second and third segments long, the second very narrow, the third hardly three-fourths as long as the second, the apical segments moderately widened.

HOLOTYPE.-Male, Lesse, Congo, July 21, 1914, (J. Bequaert).

This species is re'adily distinguished from bequaerti and liberia by much longer second and third abdominal segments, shining thorax, etc.