Hercostomus

Hercostomus is a genus of flies in the family Dolichopodidae. It is a large genus, containing more than 483 species worldwide. Multiple studies have shown that Hercostomus is a polyphyletic assemblage of species.

Species groups
The genus currently includes the following species groups, at least 25 of which are known from China:
 * Hercostomus abnormis group – China
 * Hercostomus absimilis group – China
 * Hercostomus albidipes group – China
 * Hercostomus apiculatus group – China
 * Hercostomus baishanzuensis group – China
 * Hercostomus biancistrus group – China
 * Hercostomus crassivena group – China
 * Hercostomus curvus group – China
 * Hercostomus cyaneculus group – China
 * Hercostomus digitatus group – China
 * Hercostomus digitiformis group – China
 * Hercostomus fatuus group – China
 * Hercostomus flavimaculatus group – China
 * Hercostomus flaviventris group – China
 * Hercostomus fluvius group – China
 * Hercostomus hamatus group – China(?)
 * Hercostomus incisus group – China
 * Hercostomus intactus group – China
 * Hercostomus longicercus group – China
 * Hercostomus longus group – China
 * Hercostomus nanlingensis group – China
 * Hercostomus plagiatus group – Palearctic
 * Hercostomus prolongatus group – China
 * Hercostomus quadriseta group – China
 * Hercostomus shennongjiensis group – China(?)
 * Hercostomus subnovus group – China
 * Hercostomus takagii group – China
 * Hercostomus ulrichi group – China

The Palearctic species of Hercostomus are traditionally separated into five numbered groups, based on the coloration of the femora, postocular setae and antennae:
 * Group I: Femora yellow; lower postocular setae yellow or white; antennae partly yellow
 * Group II: Femora yellow; lower postocular setae yellow or white; antennae black
 * Group III: Femora yellow; lower postocular setae black
 * Group IV: Femora black; lower postocular setae yellow or white
 * Group V: Femora black; lower postocular setae black

In 1999, Igor Grichanov divided the Afrotropical species of Hercostomus into three numbered groups. Two of these have since been separated into their own genera:
 * Group I: now Afrohercostomus
 * Group II: considered part of Hercostomus sensu stricto
 * Group III: now Neohercostomus