Functional morphology of Cardiomya cleryana (d'Orbigny, 1842) (Bivalvia: Anomalodesmata: Cuspidariidae) from Brazilian waters: new insights into the lifestyle of carnivorous bivalves

Author(s)

Machado, Fabrizio Marcondes ; Morton, Brian ; Passos, Flavio Dias

• Document type: Journal article
• Source: Journal of the Marine Biological Association of the United Kingdom; v. 97, n. 2, p. 447-462, MAR 2017.
• Web of Science Citations: 6

Abstract

Of the more than 800 Recent species of Anomalodesmata only 16 have been studied alive. The Septibranchia, comprising a number of carnivorous bivalve superfamilies, are no exception to this generalization and, until recently, no living member of this group has been studied since the 1980s. Collected from the shallow, shelf seabed off Brazil, Cardiomya cleryana is one of only a few species to have its morphology described in recent years and the first ever anomalodesmatan to be filmed alive. Important anatomical features such as a greatly extensible foot to secure itself in the sediment with a single byssal thread, exhalant siphon inter-tentacular projections and micro-papillae on the surface of the siphonal tentacles are described. Observations on the species' behaviour have revealed a lifestyle hitherto not recorded for any septibranch, indeed any anomalodesmatan. The anchoring mechanism of C. cleryana using an extraordinarily long byssal thread is described for the first time. The life position of C. cleryana is at 45 degrees to the sediment-water interface whereas other cuspidariids have been considered to orient themselves vertically. An anatomical comparison between Cardiomya and Bathyneaera has revealed close affinities. This study thus provides new insights into the morphology and behaviour of the Cuspidariidae. (AU)

• FAPESP's process: 11/50317-5 - Biodiversity and functioning of a subtropical coastal ecosystem: a contribution to integrated management
• Grantee: Antonia Cecília Zacagnini Amaral
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants