Bivalvia - Cardiidia - Grammysiidae

Synonyms: Nucula cylindrica McChesney 1859, Nucula mercerensis McChesney 1868

Full reference: B. F. Shumard and G.C. Swallow. 1858. Descriptions of new fossils from the Coal Measures of Missouri and Kansas. Academy of Science of St. Louis Transactions 1:198-227

Belongs to Cardiomorpha according to R. D. Hoare 1961

Sister taxa: Cardiomorpha digglesi, Cardiomorpha doulingensis, Cardiomorpha indica, Cardiomorpha inflata, Cardiomorpha minuta, Cardiomorpha obovata, Cardiomorpha pinguis, Cardiomorpha sublimosa

Ecology: facultatively mobile infaunal suspension feeder