Lygistorrhina edwardsina (after Matile, 1990)
Male. - Head: occiput and ocellar callus velvety brown-black. Antennae unicolourous, brown, about as long as the thorax, the first four flagellomeres slightly longer than wide, the following no longer than wide, the last a little longer. Proboscis dark yellow, very long, reaching four times the length of the fore coxa.
Thorax uniformly brown, silvery shining certain angles. Legs: all coxae brown, fore and mid femora, tibiae and tarsi yellow. Hind femur yellow-brown dorsally, strongest at the apex; hind tibia yellow to brown towards apex, regularly thickened in the middle to apex; hind tarsi brown, the basitarsus slightly thickened. Tibial spurs black, externals mid tibial spurs about one-third shorter than the internal ones, the latter up to twice the width of tibia at apex; hind external tibial spurs half of the internal, their length triple the apical width of tibia.
Wings hyaline, very slightly infuscated at apex. Costa extended over half the distance R5-Ml, but not reaching the very apex of the wing, Sc long and ending distinctly on C. Median fork reduced at the base, Ml longer. Halters yellow.
Abdomen unicolourously brown; hypopygium brown, proctiger yellow. Tergite IX arched, with a poorly developed apical brush; proctiger subapical in position. Gonostyli with strong apical tooth and a apical brush of non differentiated bristles, no distinct brush on the internal margin.
Female resembles the male. Length of the proboscis three times that of the fore coxa. Legs darker yellow. Abdomen shiny brown with some underlying irregular yellow spots.
Variations. - Fore and mid legs vary from yellow to dark brown, hind femora may be just darkened at apex; there are slight differences in the shape of tergite IX and the at the apical tooth of gonostylus in paratype male from Tanzania .
Holotype: Length of wing: 2.5 mm. Size variable: the length of the wing of the largest specimen to 3.8 mm.