Mycale adhaerens, the purple scallop sponge, is a species of marine demosponge in the family Mycalidae. Mycale is a large genus and this species is placed in the subgenus Aegogropila making its full name, Mycale (Aegogropila) adhaerens. It grows symbiotically on the valves of scallop shells and is native to the west coast of North America.
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