Yumaceras was named by Frick (1937). It was synonymized subjectively with
Pediomeryx by Savage (1941) and Janis and Manning (1998); it was reranked as
Pediomeryx (
Yumaceras) by Webb (1983); it was synonymized subjectively with
Cranioceras by Tedford
et al. (1987). It was assigned to
Pediomeryx by Webb (1983); and to
Cranioceratini by Prothero and Liter (2007). ==Fossil distribution==