Revision of the genus Torogregarina and description of Torogregarina sphinx n. sp. (Apicomplexa: Eugregarinida) from a Missouri river bank beetle, Bembidion laevigatum (Coleoptera: Carabidae), in southeastern Nebraska.

Torogregarina is revised to clarify the nature of the epimerite-protomerite complex and the method of gametocyst dehiscence, removed from the family Gregarinidae, and placed among the Hirmocystidae. Torogregarina sphinx n. sp. (Apicomplexa: Eugregarinida) is described from Bembidion laevigatum (Coleoptera: Carabidae) collected along the Missouri River near Peru, Nemaha County, Nebraska. Measurements are means in micrometers. Association is precocious and caudofrontal. Primite epimerite depressed ovoid and persistent through syzygy; length 25.2, width 41.0. Protomerite a high toroid collar between epimerite and deutomerite; length 13.5, width 35.4. Deutomerite obovoid; length 137.3, width 90.7. Total length including epimerite 172.2. Satellite epimerite protomerite complex concentrically formed by a depressed ovoid epimerite within a transversely oblong protomerite, the protruding dome of the epimerite fitting into a posterior depression on the primite and the transverse anterior margin of the protomerite mating with the posterior margin of the primite to form the syzygial junction; length 25.0, width 48.8. Deutomerite obovoid; length 113.5, width 63.5. Total length 138.6. Gametocysts roughly spherical; diameter 142.9. Gametocysts mature and dehisce by simple rupture, extruding oocysts in a single mass without an epispore packet. Oocysts axially symmetric, dolioform in dorsal aspect, concavoconcave in transverse plane, uniform in size and shape; length 5.2, terminal width 2.4, equatorial width 3.1.