Strongygaster (= Hyalomyodes) triangulifera (Loew) (Diptera: Tachinidae) is a small parasitic fly that is widely distributed in North America. It is most frequently reported as a parasitoid of adult Coleoptera, but there are scattered reports of parasitism within the Dermaptera, Hemiptera, Orthoptera, and Lepidoptera (Arnaud 1978; Purrington et al. 1990). Within the Coleoptera, species in the families Alleculidae, Bruchidae, Chrysomelidae, Cleridae, Coccinellidae, Curculionidae, Lampyridae, Meloidae, Nitidulidae, and Scarabaeidae have been reported as hosts (Gerding and Figueroa 1989; Purrington et al. 1990; Nalepa et al. 1996). This is the first record of S. triangulifera, and the first record of a tachinid, parasitizing a species of Cantharidae.