Tachytrechus is a genus of long-legged flies in the family Dolichopodidae.

[5] These 152 species are members of the genus Tachytrechus.

[6][7][8][9] Unrecognised species: The following species were moved to Aphalacrosoma:[73] The following species were moved to Paraclius: Other synonyms: The following species are listed for the genus by online databases, but are actually placed in other genera: Data sources: i = ITIS,[6] c = Catalogue of Life,[7] g = GBIF,[8] b = Bugguide.net[9]