Richardsonoceras Foerste 1933

Genus Richardsonoceras Foerste, 1933 Type species Cyrtoceras simplex Billings, 1857, from Nepean township, Ottawa, Ontario, Canada, Leray Formation, Sandbian; by original designation. Diagnosis Gradually enlarging strongly curved shells; cross section compressed with elliptical to oval cross section, convex side of conch curvature more narrowly rounded; adult body chamber slightly contracted adorally; sutures with shallow lateral lobe, slightly oblique sloping slightly adapically on the antisiphuncular side; siphuncle small, close to margin on convex side of conch curvature; segments slightly expanded. (Adopted from Kröger et al. 2009b: 286.)