Length: pictured fly measured 2.7 mm to the apex of the wing
This fly is in genus Achradocera or genus Chrysotus. The former was previously treated as a subspecies of Chrysotus. Brown et al. (2009) listed twelve species of Achradocera in the Neotropics.
Photo location: Boquete, montane forest, Chiriquí province, Panama.
American Insects site