Genus Beloitoceras Foerste, 1924

Type species

Oncoceras pandion Hall, 1861, Black River Formation, Beloit, Wisconsin, USA; by original designation.

Diagnosis

Strongly curved, relatively slender brevicones with ovate, compressed cross section. Conch smooth or with fine transverse ornament. Maximum conch diameter situated within adapical half to third of body chamber. Antisiphuncular outline of conch concave over entire length in longitudinal section, prosiphuncular outline broadly convex. Five to eight chambers per distance similar to corresponding conch cross section. Body chamber short with well developed hyponomic sinus at convex side. Siphuncle slender, situated close to convex margin of conch curvature, with subtubular segments. Septal necks short suborthochoanitic to cyrtochoanitic. Connecting rings thin. (Compiled from Sweet 1964b and Frey 1995.)