Thomson, 1926
Valves biconvex, anterior commissure plane to incipiently sulciplicate; crural processes fused in adult forming complete ringlike loop; foramen hypothyridid, mesothyridid, or epithyridid; lophophore plectolophous.
Source: Moore, 1965.
The following taxa that belong to this subfamily occur in this region:
Genus Terebratulina
Terebratulina retusa