PREDATION BY THE ORDOVICIAN ASTEROID PROMOPALAEASTER ON A PELECYPOD

An Ordovician Promopalaeaster (Echinodermata: Asteroidea) wrapped about a Cuneamya? (Mollusca: Pelecypoda) in the extraoral feeding posture characteristic of Jurassic to modern members of the Asteriidae documents an early origin for this behavioral complex. Modern asteriids are convergent on Promopalaeaster, there is no direct phylogenetic linkage between the two. This fossil occurrence, combined with the success of modern Asteriidae, demonstrates that biological evolution and geological change need not outmode complex life habits. The fossil supports the notion of asteroids as Paleozoic-type predators, and its existence suggests that asteroids were not significant contributors to changing faunal structures in shelf seas during the Phanerozoic.