Key to male Colonomyia in Australasia

1 Gonocoxites with 1 longitudinal sclerotized rib along midline of basal portion (Fig. 1A); apex of ejaculatory apodeme spade-like (Fig. 1A) .......................................................... 2

- Gonocoxites with 2 distant longitudinal sclerotized ribs; apex of ejaculatory apodeme with 2 pairs of slender processes ........... albicaulis COLLESS (SE Australia including Tasmania)

2 Gonostylus with dorsomesal lobe (Fig. 2); parameres apically two-lobed, lateral lobe slender and apically serrate, mesal lobe wide and rounded (Fig. 2) .. tasmanica sp. n. (Tasmania)

- Gonostylus without dorsomesal lobe; parameres tusk-like and apically pointed ............... ...................................................................... rakelae HIPPA &ZASCHHOF (New Guinea)