Allohercostomus is a genus of flies in the family Dolichopodidae.[1] [2] It includes three species from China and Nepal. Members of the genus are metallic green in color and are small in size, with a body length of 2.5–3.2 mm and a wing length of 2.8–3.4 mm. The generic name is a combination of the prefix allo- (from the Ancient Greek Greek, Ancient (to 1453);: ἄλλος,, meaning "other") with the generic name Hercostomus. In Brooks (2005)'s phylogenetic analysis of the subfamily Dolichopodinae, Allohercostomus was hypothesized to be the most basal member of the subfamily based on a triangular depression present on the scutum in front of the scutellum, a plesiomorphy lost in other members of the subfamily. It can also be distinguished from other members of Dolichopodinae by features such as the bottoms of its eyes being contiguous.[1]