Genus Eosomichelinoceras J.-Y. Chen, 1974

Type species

Eosomichelinoceras huananense J.-Y. Chen, 1974, from the Middle Ordovician of Southwest China; by original designation.

Diagnosis

Smooth or transversally striated, slender, orthoconic baltoceratids with narrow, tubular siphuncle. Siphuncle is eccentric with rSP of more than 0.2, and with rSD ≈ 0.2 or less. Septal necks are orthochoanitic. Endosiphuncular or cameral deposits are not known (adopted from Kröger et al. 2007).