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Five-ribbed Kelp

Costaria costata


A brown kelp with blades that have 5 parallel ribs running its length. Three ribs project on one side of the blade and 2 ribs on the other. Between the ribs the blade is profusely wrinkled or puckered. This blade was about 2 ft (61 cm) long. It can grow to over 6 ft.


Spotted in a tide pool at Tongue Point.

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Brian38 a year ago

Thank you Neil.

Neil Ross
Neil Ross a year ago

Cool. Looks like a big, flat slug. Amazing spotting, Brian.

Spotted by

Washington, USA

Spotted on Apr 20, 2019
Submitted on May 1, 2019

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