Anomalodesmata
Quick Summary
The Anomalodesmata are a subclass of bivalves characterized by highly variable shells, which can be equivalve or inequivalve and may gape. Their hinge plates are thickened but generally lack teeth, and their shells have two or three layers, with the inner layer being nacreous. Most Anomalodesmata are hermaphroditic and marine, primarily burrowing, though some are epibyssate or cemented. This subclass includes the Pholadomyoida order, which exhibits diverse shell forms and feeding strategies, from suspension feeding to predation, particularly in deep-sea species. Ecologically, Anomalodesmata share diverse habitats with other bivalve subclasses, with shallow-water species being highly specialized and deep-sea species often being predators. Some Anomalodesmata have adapted their ctenidia into septibranchs for predation, creating water currents to capture prey.123
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- bivalveEcology and habitats
…diversity of habitat with the Anomalodesmata, which have radiated along two lines: shallow-water species that are highly specialized, are hermaphroditic, occupy narrow niches, and have a short planktonic stage and deep-sea species that are even more specialized, most being predators.
Read More…diversity of habitat with the Anomalodesmata, which have radiated along two lines: shallow-water species that are highly specialized, are hermaphroditic, occupy narrow niches, and have a short planktonic stage and deep-sea species that are even more specialized, most being predators.
Read More - bivalveCritical appraisal
The subclass Anomalodesmata, however, is itself possibly too narrowly demarcated, and some authorities would, for example, separate the deepwater carnivorous septibranchs from the shallow-water pholadomyoids into their own order, the Septibranchoida.
Read MoreThe subclass Anomalodesmata, however, is itself possibly too narrowly demarcated, and some authorities would, for example, separate the deepwater carnivorous septibranchs from the shallow-water pholadomyoids into their own order, the Septibranchoida.
Read More