Pyropteron muscaeforme, the thrift clearwing, is a moth of the Sesiidae family. It is known from most of Europe. A small of the genus, the wingspan is 15–18 mm. It is further distinguished by narrow clear (transparent) spaces on the blackish, or bronzy, fore wings. There are three whitish bands on the body, and traces of a whitish line along the middle of the back.
Adults can be found on the flowers of the host plant, as well as on Thymus vulgaris. It overwinters as a larva. The larvae feed on in the roots and crown of Armeria maritima.