Gastropoda - Prosobranchia - Orthonematidae

Full reference: H. Chronic. 1952. Molluscan fauna from the Permian Kaibab Formation, Walnut Canyon, Arizona. Geological Society America Bulletin 63(2):95-166

Belongs to Orthonema according to D. H. Erwin 1988

Sister taxa: Orthonema amissidecoris, Orthonema ascensus, Orthonema borovskensis, Orthonema carbonaria, Orthonema cochleoides, Orthonema frequens, Orthonema hulusitaiensis, Orthonema illineatus, Orthonema inornatum, Orthonema knighti, Orthonema liratum, Orthonema marvinwelleri, Orthonema nakazawai, Orthonema nebrascense, Orthonema paedice, Orthonema panxianensis, Orthonema paulum, Orthonema paxillus, Orthonema pygmaeum, Orthonema rectimurum, Orthonema salteri, Orthonema sayrei, Orthonema semiornatum, Orthonema silinae, Orthonema simplex, Orthonema socorroense, Orthonema strigatum, Orthonema subtaeniatum, Orthonema telescopiforme, Orthonema tirusum, Orthonema tricingulatum, Orthonema youngianum

Type specimen: AMNH 27117:1, a shell. Its type locality is Rimmy Jim Tank, Kaibab Formation, Coconino County, which is in a Roadian marine limestone in the Kaibab Formation of Arizona.

Ecology: epifaunal

Average measurements (in mm): shell width 3.33, shell diameter 3.74