''Pagurus pollicaris'' is a

hermit crab Hermit crabs are anomuran decapod crustaceans of the superfamily Paguroidea that have adapted to occupy empty scavenged mollusc shells to protect their fragile exoskeletons. There are over 800 species of hermit crab, most of which possess an as ...

commonly found along the

Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe an ...

coast of North America from

New Brunswick New Brunswick (french: Nouveau-Brunswick, , locally ) is one of the thirteen provinces and territories of Canada. It is one of the three Maritime provinces and one of the four Atlantic provinces. It is the only province with both English and ...

to the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...

. It is known by a number of common names, including ''gray hermit crab'', ''flat-clawed hermit crab'', ''flatclaw hermit crab'', ''shield hermit crab'', ''thumb-clawed hermit crab'', ''broad-clawed hermit crab'', and ''warty hermit crab''. ''P. pollicaris'' inhabits the shells of shark eye snails and

whelk Whelk (also known as scungilli) is a common name applied to various kinds of sea snail. Although a number of whelks are relatively large and are in the family Buccinidae (the true whelks), the word ''whelk'' is also applied to some other marin ...

s. It grows to a length of and a width of . The shell is often shared by the

commensal Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit fro ...

zebra flatworm ('' Stylochus ellipticus''). The diet of the flat-clawed hermit crab comprises organic matter,

alga Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

e, and sometimes other hermit crabs.

Fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of ...

are the most important predators of this species.

References

{{Taxonbar, from=Q3933098 Hermit crabs Crustaceans of the Atlantic Ocean Crustaceans described in 1817