Mossy Chiton (Mopalia muscosa)

Description: Mossy chitons are masters of camouflage. Like all chitons, they have eight plates that are typically a gray, brown, or green tone that blends in with the rocks and other tide pool creatures. Mossy chitons are named for the fuzzy moss-like hairs that cover their girdle (the flesh that wraps around the edge of their plates). They can get up to 8 cm long. The mossy chiton and its close relative, the hairy chiton (Mopalia ciliata), look very similar to each other. When identifying the mossy chiton, look for thick, stiff hairs compared to the shorter, softer hairs of the hairy chiton - this may be best differentiated by feel.

Habitat: Mossy chitons range from Alaska to Baja California, Mexico. They can be found from the high intertidal to the low intertidal zone of rocky beaches.

Diet: Like other chitons, mossy chitons eat algae. They seem to have a preference for Turkish washcloth (Mastocarpus papillata), nailbrush seaweed (Endocladia muricata), or the green algae in the genus Cladophora.

Tide Pool Tidbits:

• The plates on a mossy chiton often have other organisms such as algae and barnacles growing on them.

• Mossy chitons each have their own territory or home range that they occupy, typically only 51 cm.

References: The New Beachcomber’s Guide to the Pacific Northwest by J Duane Sept, Walla Walla University