Craniata (brachiopod)

Craniata is a class of brachiopods originating in the Cambrian period and still extant today. They have calcitic inarticulated shells that are subcircular in outline. This class of brachiopods has an unsupported lophophore and is always attached to a hard substrate in the fossil record. This hard substrate is usually another brachiopod. The plicae from the host brachiopod will then appear within the shell of the craniata.
Craniata is the only class within the subphylum Craniiformea. The class Craniata is divided into three orders, one of which is still extant (Craniida).