New species without dead bodies: a case for photo-based descriptions, illustrated by a striking new species of Marleyimyia Hesse (Diptera, Bombyliidae) from South Africa

A new bombyliid species Marleyimyia xylocopae Marshall & Evenhuis, sp. n., an apparent mimic of the carpenter bee Xylocopa flavicollis (De Geer), is described from South Africa on the basis of photographs only. The pros and cons of species descriptions in the absence of preserved type specimens are discussed.