Milichiella variata
Differs from congeners in the combination of shiny black mesonotum, yellow halter, thorax with numerous acrostichal setae, labella about as long as palpus, black legs, male T2-5 silvery microtomentose, except for shiny tip of T5.
Male coloration and vestiture: frons subshiny black, ocellar triangle and upper orbital plates shiny black, lunule dark brown, basoflagellomere basomedially brown, face grey brown microtomentose, palpus black; thorax with mesonotum shiny black, scutellum brown microtomentose, pleura slightly brown microtomentose except for shiny spots on an- and katepisternum, wing hyaline, veins yellow, brown spot at tip of vein R1 absent, calypter white, halter yellow, legs black, fore and hind tarsus with dark yellow brush; abdomen with T2-5 silvery microtomentose, except for shiny tip of T5. Female coloration and vestiture: halter yellow, abdomen with T1-4 brown microtomentose, T5 shiny.
Morphology. Head: frons with 2 or 2+0.4 orbital and 2 frontal setae, anterior frontal seta medioclinate. In males frons 2.0x as wide at posterior margin than at base of antenna, arista about 4.8x as long as basoflagellomere wide, pubescence on arista very short, posterior eye margin with narrow notch (3oc) and emargination (2oc).
Thorax: 2 dc, 1 prsc, 1 pprn, 1 prs, 2 keps setae, posterior prsc less than 0.8x as long as posterior dc, seta between posterior prsc and posterior dc absent. Wing with vein R4+5 and M1 converging (2.4), and ultimate section of vein M1 3.2x as long as penultimate section. Fore femur normal setulose, tibial organ absent.
Male abdomen: posteromedial triangular projection of T1 into T2 weak. Tergal chaetotaxy: T2 anterolateral corner with single line of setae, T2-4 posterior margin with 1 row of setulae. S5 1.3x as long as wide, 1.8x as long and 2.0x as wide as S4, rectangular, posterior margin indented, setulose on posterior 3/4 and nearly up to lateral margins. Male genitalia same as M. brevirostris, 1 seta on subepandrial plate, surstylus same as M. brevirostris, structure of lateral surface weak honeycomb-like, more like longitudinal creases, medial surface without setulae.
Special characters: labella about as long as palpus, thorax 0.8-0.9x as long as wide, numerous acrostichal setae, silvery microtomentum long.
Remarks. Variety or separate species from Mexico with brown calypter margin, mid basitarsus brown, surstylus narrower at base and sternite intermediate between M. brevirostris and M. longirostris.
Body length: 1.6-1.9 mm; wing length: 1.5-1.8 mm.