General trends in predation and parasitism upon inoceramids

Abstract

Inoceramid bivalves have a prolific evolutionary history spanning much of the Mesozoic, but they dramatically declined 1.5 Myr prior to the Cretaceous-Tertiary boundary. Only the enigmatic genus Tenuipteria survived until the terminal Cretaceous event. A variety of hypotheses have attempted to explain this disappearance. This study investigates the role that predation and parasitism may have played in the inoceramids' demise. Inoceramids show a range of predatory and parasitic features recorded in their shells ranging from extremely rare bore holes to the parasite-induced Hohlkehle. The stratigraphic record of these features suggests that they were virtually absent in inoceramids prior to the Late Turonian and became increasingly abundant through the remainder of the Cretaceous. These results suggest that predation and parasitism may have played a role in the inoceramid extinction, but more rigorous, quantitative data are required to test this hypothesis further.