Gatunek typowy
Eumorphoceras bisulcatum Girty, 1909

Opis

Shell subdiscoidal to thick discoidal; at early maturity ribs are sickle shaped, bending orad and dying out on each flank at the ventrolateral sulcus; venter rounded;  in late maturity ribs absent, but longitudinal sulcus may continue weaker on outer flanks; sculpture principally of growth lines, forms prominent ventrolateral salients and deep ventral sinus; venter becomes angular at late stage; suture like that of Girtyoceras but ventral lobe generally little more deeply divided than in specimens of that genus at same diameter..

Synonimy

Zasięg czasowy

Carboniferous; Late Serpukhovian – Early Bashkirian

Literatura

Girty, G.H. 1909. The fauna of the Caney Shale of Oklahoma. Bulletin, U.S. Geological Survey, 377: 1-106, Washington.

Gordon, M. Jr. 1965. Carboniferous Cephalopods of Arkansas. Professional Papers, U.S. Geological Survey 460: 1-322.