Sunday, July 31, 2022

Tortoise Shell Limpet (Searsport, Maine)

Acmaea testudinalus

I found a nearly intact limpet shell this morning, along the line of seaweed left by the last high tide. When I was snorkeling a week or so ago, I saw lots of them on the rocks mixed in with the barnacles and whelks. I remember hunting for these as a child on that very beach.

They are a cold water species, common in Maine coastal waters. As adults they live in the lower inter-tidal zone. They go through several larval stages before settling down to life on the rocks. The sexes are separate (not hermaphrodites).

They are a true limpet, one of the sea snails, and a member of the Lottiidae family. Individuals can get to over an inch across. Their shell peak is off-center.

They are herbivores, grazing on algae with their radula. They use their foot to adhere to rocks and to move across them.