Pagurus pollicaris

crustacean

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Last updated

June 30, 2026

Quick Summary

Pagurus pollicaris is a species of hermit crab found in the Atlantic coastal waters of North America. These crustaceans are known for using empty snail shells or other hollow objects to protect their soft, asymmetrical abdomens.1

Hermit crabs, including Pagurus pollicaris, have a body structure adapted for this lifestyle. Their first pair of legs is modified into pincers, with the right one typically being larger. These pincers help cover the shell's opening when the crab retreats inside. They walk on their second and third pairs of legs and use the smaller fourth and fifth pairs to grip the inside of their shell.1

As Pagurus pollicaris grows, it must find larger shells to accommodate its increasing size. The availability of suitable shells can lead to intense competition among hermit crabs.1

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hermit crab
Pagurus pollicaris, a large hermit crab of the Atlantic coastal waters of North America, is reddish brown and about 10 to 12 cm (4 to 5 inches) long. P. longicarpus, a much smaller hermit crab, occurs in shallow U.S. Atlantic coastal waters.
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Pagurus pollicaris, a large hermit crab of the Atlantic coastal waters of North America, is reddish brown and about 10 to 12 cm (4 to 5 inches) long. P. longicarpus, a much smaller hermit crab, occurs in shallow U.S. Atlantic coastal waters.
Read More