Shell-dwelling
Guides
Clibanarius
Clibanarius is a genus of hermit crabs in the family Diogenidae, comprising approximately 60 valid species as of 2025. Members possess soft, asymmetrical abdomens protected within scavenged gastropod shells. While predominantly marine, the genus includes C. fonticola, the only known hermit crab species to complete its entire life cycle in freshwater. The genus exhibits broad geographic distributions, with feeding rates documented to vary with temperature.
Coenobita clypeatus
Caribbean Land Hermit Crab, Soldier Crab, West Atlantic Crab, Tree Crab, Purple Pincher
Coenobita clypeatus is a terrestrial hermit crab native to the western Atlantic and Caribbean region. Adults inhabit coastal environments and can be found considerable distances inland, often burrowing under tree roots. The species exhibits complex social behaviors including shell fighting, vacancy chains for resource acquisition, and size-dependent dominance hierarchies. It relies on scavenged gastropod shells for protection and water retention, with shell availability directly limiting population density and individual growth.
Pagurus
Pagurus is a genus of marine hermit crabs comprising approximately 170 described species. Members possess an uncalcified, asymmetrical abdomen that they protect by inhabiting empty gastropod shells. These decapod crustaceans occupy diverse marine habitats from intertidal zones to deep continental slopes. The genus exhibits broad geographic distribution across temperate and tropical waters worldwide.
Pagurus acadianus
Acadian hermit crab
Pagurus acadianus is a marine hermit crab species in the family Paguridae, first described by J.E. Benedict in 1901 from specimens in the western Atlantic. It is distinguished from the closely related Pagurus bernhardus by morphological features including larger eyestalks, shorter chelae fingers, and sharper chelipeds. The species inhabits rocky intertidal zones and exhibits seasonal population fluctuations, with peak abundance in June and reduced activity from November through March. It has been documented as the most abundant hermit crab in some Maine localities, though 95.4% of museum records represent preserved specimens rather than living observations.
Pagurus hirsutiusculus
Pacific Hairy Hermit Crab, Hairy Hermit Crab
Pagurus hirsutiusculus is a small marine hermit crab found along the North Pacific coast from Alaska to California and Japan. Adults reach up to 70 mm body length in northern populations, with southern populations being smaller and less hairy. The species is distinguished by dense body hair, white and blue bands on walking legs, and grayish-brown antennae with white bands. It inhabits the intertidal zone to depths of 110 m, commonly occupying empty gastropod shells for protection.
Pagurus longicarpus
long-clawed hermit crab, long-wristed hermit crab
Pagurus longicarpus is a small hermit crab species reaching up to 12.7 mm in shell length. It inhabits empty gastropod shells, primarily those of periwinkles, oyster drills, and mud snails. The species is distributed along the Atlantic coast of North America from Nova Scotia to Florida and westward to Texas, including the Gulf of Mexico. It occupies intertidal and subtidal habitats to depths of 200 meters, with seasonal movements between shallow tidal pools in warmer months and deeper waters in winter.
Pagurus pollicaris
flat-clawed hermit crab, flatclaw hermit crab, gray hermit crab, shield hermit crab, thumb-clawed hermit crab, broad-clawed hermit crab, warty hermit crab
Pagurus pollicaris is a marine hermit crab found along the Atlantic coast of North America. It inhabits empty gastropod shells, particularly those of shark eye snails and whelks, and reaches approximately 31 mm in length. The species is distinguished by its broad, flat claws that can lock together to form an operculum when the crab withdraws into its shell.