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Purple Shore Crab

Hemigrapsus nudus

Description:

Common under stones and among seaweeds from Alaska to Baja California, the Purple shore crab has a carapace (main body shell) of about 2 inches (56.2 mm.) wide in males, and one and a half inches (34 mm.) in females. The shell is smooth and convex, usually purple, but sometimes greenish yellow or reddish brown. Its easily distinguished from the slimmer, striped shore crab by the red or purplish spots on its claws.

Notes:

Their diet consists mainly of diatoms and small green algae scraped from rocks. In the Monterey Bay, breeding occurs in winter; the size of the brood varies with the size of the female... to over 36,400 eggs in a 34 mm. crab.

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Eva Varga
Spotted by
Eva Varga

Oregon, USA

Spotted on Jul 18, 2012
Submitted on Aug 29, 2012

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