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Acorn Barnacle

Semibalanus balanoides


Deeply grooved barnacles. Feeding behavior in photos 4-6


Boulders on the edge of the seashore

1 Species ID Suggestions

Rock Barnacles
Semibalanus balanoides Semibalanus balanoides

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1 Comment

Christine Y.
Christine Y. 5 years ago

You can tell that these are Semibalanus because when you look inside the dead ones, you can see rock, which means that the base is membranous, not calcareous. The big ones look like they are 2 years or older. Love the pictures that you added of the cirri!

Spotted by

Maine, USA

Spotted on Apr 21, 2016
Submitted on May 17, 2016

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