A first fossil member of the Ctenodiscidae (Asteroidea, Echinodermata)

Paleoctenodiscus campaniurnis, a new species and genus assigned to the Ctenodiscidae, is based on a single specimen collected from beneath a turbidite flow from the Cretaceous (Campanian) of Baja California. Modern ctenodiscids are sediment feeders that spend much of their lives beneath the surface; Paleoctenodiscus also was a sediment feeder, but it lived only partially buried. The occurrence establishes a minimal geologic age for the evolution of cribriform organs. A scenario for the evolution of sediment ingestion in asteroids is suggested. -Author