Symbion

Genus of microscopic organism that are commensal with lobsters

Symbion is a genus of commensal aquatic animals, less than 0.5 mm wide, found living attached to the mouthparts of cold-water lobsters. They have sac-like bodies, and three distinctly different forms in different parts of their two-stage life-cycle. They appear so different from other animals that they were assigned their own phylum, Cycliophora, also called wheel wearers, shortly after being discovered in 1995.

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