Gastropoda - Prosobranchia - Pseudozygopleuridae

Alternative combinations: Palaeostylus (Stephanozyga) subnodosa, Pseudozygopleura (Stephanozyga) subnodosa

Full reference: J. B. Knight. 1930. The gastropods of the St. Louis, Missouri, Pennsylvanian outlier: the Pseudozygopleurinae. Journal of Paleontology Memoir 4(4):1-88

Belongs to Stephanozyga according to P. J. Wagner 2011

Sister taxa: Pseudozygopleura (Stephanozyga) lisaspira, Pseudozygopleura (Stephanozyga) nishimurai, Stephanozyga granda, Stephanozyga lisaspira, Stephanozyga magna, Stephanozyga nodosa, Nodozyga rugifera, Nodozyga longnorensis

Type specimen: YPM 12990, a shell. Its type locality is Locality 42. Steep embankment along Pershing Ave. at Cleveland Walk., which is in a Moscovian carbonate limestone in the Fort Scott Formation of Missouri.

Average measurements (in mm): shell 35.0 x 11.0