Mammalia - Artiodactyla - Protoceratidae

Alternative combination: Prosynthetoceras trinitiensis

Full reference: T. H. Patton and B. E. Taylor. 1971. The Synthetoceratinae (Mammalia, Tylopoda, Protoceratidae). Bulletin of the American Museum of Natural History 145(2):119-218

Belongs to Lambdoceras according to D. R. Prothero 1998

Sister taxa: Lambdoceras hessei, Lambdoceras siouxensis

Type specimen: Its type locality is Trinity River Pit 1, which is in a Barstovian terrestrial horizon in the Fleming Formation of Texas