Rhynchonellata - Terebratulida - Cryptonellidae

Alternative combination: Heterelasma geniculata

Full reference: F.G. Stehli. 1954. Lower Leonardian Brachiopoda of the Sierra Diablo. Bulletin of the American Museum of Natural History 105(3):257-358

Belongs to Heterelasma according to G. A. Cooper and R. E. Grant 1976

Sister taxa: Dielasma (Heterelasma) semitarium, Heterelasma angulatum, Heterelasma concavum, Heterelasma contortum, Heterelasma contrerasi, Heterelasma gibbosum, Heterelasma glansfagea, Heterelasma lenticularia, Heterelasma magnum, Heterelasma ngariensis, Heterelasma pentagonum, Heterelasma quadratum, Heterelasma shumardianum, Heterelasma solidum, Heterelasma sulciplicatum, Heterelasma venustulum

Type specimen: AMNH 27333

Ecology: stationary epifaunal suspension feeder

Average measurements (in mm): shell 7.85 x 6.84