ABSTRACT
Many specimens of Micraster coranguinum from the Upper Chalk (M. coranguinum Zone) of Long Bredy in southern England show test damage which may be ascribed to the work of predators. Some show borings into or through the test, of which most appear to be attachment sites of acrothoracic barnacles and clionid sponges or excavations by annelid worms, but others are comparable with holes formed by present-day parasitic or predatory gastropods. Nearly 10% of over 400 specimens show test fractures in the apical region, inferred to be the work of a predator attacking the gonads beneath. Almost all of the tests show post-mortem encrustation, notably by cementing bivalves and the sponge Porosphaera and less commonly by bryozoa and serpulids, which never pre-dates the fractures. Some borings and these particular fractures are therefore interpreted as evidence of true predation on living animals. Predation has been claimed to be the driving force behind many evolutionary trends in echinoids, and it is likely to have been a contributory factor favouring an infaunal adaptive strategy also in Micraster.
