Gastropoda - Prosobranchia - Orthonematidae

Full reference: J. B. Knight. 1934. The gastropods of the St. Louis, Missouri, Pennsylvanian outlier. VIII. The Turritellidae. Journal of Paleontology 8(4):433-447

Belongs to Orthonema according to J. B. Knight 1934

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 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 striatonodosum, Orthonema strigatum, Orthonema subtaeniatum, Orthonema telescopiforme, Orthonema tirusum, Orthonema tricingulatum, Orthonema youngianum

Type specimen: YPM 13944, a shell. Its type locality is Locality 6. 200 ft. north of Clayton Rd., 1st street west of Kirkwood-Ferguson Trolly tracks, "Davis Place" subdivision, Clayton, which is in a Desmoinesian carbonate limestone in the Pawnee Formation of Missouri.

Ecology: epifaunal

Average measurements (in mm): shell 7.10 x 4.10