Published online by Cambridge University Press: 31 May 2012
Four species are recognized in the genus Holcopsis Enderlein: bifenestrata (Osten Sacken 1886), fenestrata Enderlein 1923, bequaerti (Philip 1943) and pilifera (Philip 1943). All specimens for which the locality is known are from the State of Durango, Mexico. The genus is characterized and its possible relationship with Bolbodimyia Bigot is indicated. Collection data for all known specimens are given. The species are characterized by the use of a descriptive key. The wing, third antennal segment, and second palpal segment of the female of each species is illustrated.