There are sporadic populations in the Huachucas and Santa Catalina Mtns; occasional individuals appear elsewhere, almost always along dirt roads. There are no reports of them nectaring at blossoms. As opposed to the previous species, adults of inviernus are 9-10 mm in length, mostly black, and heavily clothed in a mixture of dark and light somewhat curly pile. The halteres are light above and brown below. The wings shade from smoky anteriorly to hyaline rearward, have 3 submarginal cells, and their costal areas are heavily serrated. The proboscis is very short. Note its very local occurrence and the winter flight at middle altitudes of 1,275-1,750 m.  It is similar to atratulus, nigripennis and melanoceratus but does not key out readily to any of them.  We understand that upon further investigation, it may turn out to be conspecific with one of them.