Small, black fly. Wings are usually broken off, leaving a short stub; if the wing is complete, than crossvein dm-cu is absent. In females the abdominal sternites 1-5  are absent and the membrane is covered instead with numerous sclerotized spots bearing a short seta each.

Diagnostic description

Distinguished from Carnus occidentalis by the relatively longer surstylus (apical width/total length 0.40) and by the long paraphysis in lateral view (0.54 greatest width/length). Separated from C. orientalis by having a wider interocular distance; deeper cheek; and male abdominal sternites rectangular (not square).