Genus Terebratulina Orbigny, 1847

Type species:Anomia retusa Linnaeus, 1758 (recent North Atlantic species).

Biconvex shells with thin radial sculpture. Hinge-margin (or cardinal margin) is short and almost straight. Deltidial plates are disjunct (open foramen). Pedicle collar is short but expressed well. Pedicle connects to substrate by means of brush-like surface with numerous short filaments (rhizoids). Brachial skeleton is short and looks like ring, formed with transversal band and crural processes.

There are no less than 27 species in recent fauna of the World Ocean. In the northern part of the Sea of Japan only one species is known.