Rank Species | Scientific name Mopalia mucosa Higher classification Mopalia | |
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Similar Mopalia, Katharina tunicata, Mopalia ciliata, Tonicella lineata, Tonicella | ||
Mopalia muscosa (Gould, 1846) is a species of chiton, a polyplacophoran, an eight-plated marine mollusk. It is a northeastern Pacific species which occurs from British Columbia, Canada, to Baja California Mexico.
This species is found in the middle and lower intertidal zone on exposed rocky shores. Mopalia muscosa can be 40 to 55 mm (1.6 to 2.2 in) in length. In life it is quite often covered with growths of algae such that it is difficult or impossible to really see the plates. The girdle is covered in coarse hair-like bristles or "setae". Some have even been known to be covered in a sort of brown sludge which resembles refried beans. The eight shelly plates are brown or dark grey, and are a turquoise blue on the inner surfaces. Some are so fluorescent that they are known to glow in the dark and flash pink polka dots.