Gastropoda - Prosobranchia - Orthonematidae

Alternative combination: Goniasma silinae

Synonyms: Geolcomia rara Licharev 1975, Orthonema rara Licharev 1975

Full reference: B.K. Licharev. 1975. Carboniferous gastropods from the region of the River Kavabolka. Trudy Vsesoyuzniei Navcho-Issledovatelbskii Geologicheskii Institut 206:5-183

Belongs to Orthonema according to A. V. Mazaev 2002

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

Type specimens:

• Orthonema silinae: CGM StP 9758/109, a shell
• Orthonema rara:

Average measurements (in mm): shell 35.6 x 11.2