Genus Nybyoceras Troedsson, 1926

Type species

Actinoceras (Nybyoceras) bekkeri Troedsson, 1926 from Niibi, Estonia, Pirgu Regional Stage, late Katian; by original designation.

Diagnosis

Slender straight shell, eccentric siphuncle; adnation areas broad ventrally on posterior side of segments; dorsally on adoral side; septal necks very short and adnate to adoral surface of septa, endosiphuncular canal system reticulate to curved, branching radial canals. (Compiled from Teichert 1964.)