(Scacchi and Philippi, 1844)
Description:
The shell is circular to transversely oval in outline, with a maximum length of 5 mm and width of 6 mm. The dorsal valve is almost flat and the external surfaces are smooth except for concentric growth lines. The shell is endopunctate, yellow or white in colour. The pedicle foramen is large and extends into the dorsal valve; narrow deltidial plates are present.
Internal:
The crura and brachial loop are short. Spicules are common in the body tissue (P. anomioides internal).
Habitat:
It occurs at depths from 80 to 750 metres, sometimes attached to dead regions of corals.
Distribution:
Off the Hebrides, to the west of Ireland, in the Western Approaches and the Bay of Biscay. Elsewhere it has been found in the Mediterranean and off Florida, Cuba and the West Indies.