Trachydermon (Spongioradsia) Pilsbry, 1894 (original rank) Spongioradsia is a genus of polyplacophoran molluscs.
Spongioradsia became extinct during the Oligocene period.
This prehistoric mollusc article is a stub.
You can help Wikipedia by expanding it.This Chiton-related article is a stub.
You can help Wikipedia by expanding it.