Habrocytus caudiger Graham, 1969: 548
Female.- Differs from that of albipennis as follows: Length 4-4.8 mm. Fore wing with M 1.65-1.9 times as long as ST; venation fulvous, parastigma and stigma sometimes brownish testaceous. Metasoma relatively longer, 1.3-1.5 times as long as head plus mesosoma, 3.4-4 times as long as broad, more compressed, conical, broadest at about level of apex of basal tergite, in albipennis usually with its broadest part somnewhat farther back; last tergite 1.35-1.55 times as long as its basal breadth. Malar space from somewhat more than half to nearly two thirds the length of an eye.
Male.- Resembles that of albipennis as but is larger (length 3.4-3.5 mm
Biology.- Reared from Terellia longicauda (Mg.) in flower head of Cirsium eriophorum.