Key to the species of Medeventor Wheeler

1. First flagellomere rounded; facial carina broad; palpus swollen; eyes bare; hypandrium open posteriorly; epandrial setulae distributed mostly laterally; tip of surstylus pointed, in posterior view; cerci without long setae.......... M. nubosus Wheeler

1’. First flagellomere with an acute upper corner; facial carina narrow; palpus elongate; eyes hairy; hypandrium closed posteriorly; epandrial setulae uniformly spread; tip of surstylus pointed or rounded, in posterior view; cerci with a pair of long setae..................................................................................................... 2

2. Last two or three hind tarsomeres dark; sternite 6 well developed, bent up towards the tip of the terminalia, near to the distiphallus; tip of gonites flattened; epandrium with many setulae; surstylus pointed, in posterior view; cerci pointed, separated, each with a long seta on it that bent upward; 3.8 mm long..................................... M. tschirnhausi, sp. n.

2’. All tarsomeres yellow; sternite 6 weakly developed; apex of gonites rounded; epandrium with very few setulae; surstylus rounded, in posterior view; cerci rounded, fused basally, each with a long seta on them that bent downward; 2 mm long........................................................................................... M. minimus, sp. n.