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 asymmetric abdomen concealed by a snug-fitting shell. Hermit crabs' soft (non-calcified) abdominal exoskeleton means they must occupy shelter produced by other organisms or risk being defenseless.
Anomura is a group of decapod crustaceans, including hermit crabs and others. Although the names of many anomurans include the word crab, all true crabs are in the sister group to the Anomura, the Brachyura.
Carcinisation is a form of convergent evolution in which non-crab crustaceans evolve a crab-like body plan. The term was introduced into evolutionary biology by L. A. Borradaile, who described it as "the many attempts of Nature to evolve a crab".
The halloween hermit crab, also known as the striped hermit crab or orange-legged hermit crab, is a brightly colored aquatic hermit crab of the family Diogenidae. Besides its ability to routinely clean algae in aquaria, the halloween hermit crab's festive striped coloration also appeals to enthusiasts; it is considered the most brightly colored hermit crab in normal aquarium use.
The hairy stone crab is a crab-like anomuran crustacean that lives in the littoral zone of southern Australia from Bunbury, Western Australia, to the Bass Strait. It is the only species in the family Lomisidae. It is 1.5–2.5 cm (0.6–1.0 in) wide, slow-moving, and covered in brown hair which camouflages it against the rocks upon which it lives.
Coenobita brevimanus is a species of terrestrial hermit crab belonging to the family Coenobitidae, which is composed of coastal living terrestrial hermit crabs. From there it belongs to the genus Coenobita, one of two genera split from the family, which contains sixteen species. The Latin origins of the species name, brevimanus, come from the adjective brevis ("small") and the noun manus ("hands"). It is known as the Indos crab or Indonesian crab because it is primarily distributed throughout the Indo-Pacific.
Hippoidea is a superfamily of decapod crustaceans known as sand crabs or mole crabs.
Calcinus elegans, also known as the blue line hermit crab, is a small, tropical hermit crab.
Diogenes pugilator is a species of hermit crab, sometimes called the small hermit crab or south-claw hermit crab. It is found from the coast of Angola to as far north as the North Sea, and eastwards through the Mediterranean Sea, Black Sea and Red Sea. Populations of D. pugilator may be kept in check by the predatory crab Liocarcinus depurator.
The Pylochelidae are a family of hermit crabs. Its members are commonly called the 'symmetrical hermit crabs'. They live in all the world's oceans, except the Arctic and the Antarctic, at depths of 2,000 m (6,600 ft). Due to their cryptic nature and relative scarcity, only around 60 specimens had been collected before 1987, when a monograph was published detailing a further 400.
Diogenes is a genus of hermit crabs.
Dardanus pedunculatus, commonly referred to as the anemone hermit crab, is a species of hermit crab from the Indo-Pacific region. It lives at depths of up to 27 m and collects sea anemones to place on its shell for defence.
Clibanarius fonticola is a species of hermit crab from Vanuatu. It lives exclusively in fresh water, the only hermit crab in the world to do so. While a number of other hermit crabs are terrestrial or live in estuarine habitats, and certain brackish water species can tolerate low salinity levels for a time, no other hermit crab spends its entire life in fresh water; the only other fully freshwater anomurans are the South American aeglids.
Pagurus sinuatus is a large species of hermit crab found in Australia and the Kermadec Islands. It is red or orange in colour with coloured bands on the legs and patches on the body.
Cancellus is a genus of hermit crabs in the family Diogenidae. Members of this genus are most commonly found living in small crevices in the outer continental shelf at mesophotic depths. They can be found living in rocks, sponges, and algae among other places. The genus has a cosmopolitan distribution. Four species are known from the western Atlantic.
Albunea carabus is a rare species of "sand crab" or "mole crab" in the genus Albunea. It lives in shallow, turbulent waters in sandy areas of the tropical eastern Atlantic Ocean and the Mediterranean Sea.
Calcinus verrillii, commonly known as Verrill's hermit crab, is a species of hermit crab in the genus Calcinus which is endemic to Bermuda. It was first described by the American zoologist Mary J. Rathbun and named in honour of the American zoologist Addison Emery Verrill, who spent much time with his students studying the geology and marine fauna of Bermuda.
Diogenes heteropsammicola is a species of hermit crab discovered during samplings between 2012 and 2016 in the shallow waters of the Japanese Amami Islands. This D. heteropsammicola is strongly associated with the walking corals. This hermit crab species is unique due to the discovery that they use living, growing coral as a shell. The live in the inside of the coral and vary from other types of hermits. Crustaceans of this type commonly replace their shell as the organism grows in size, but D. heteropsammicola are the first of their kind to use solitary corals as a shell form. Heteropsammia and Heterocyathus are the two solitary corals that this hermit species has been observed as occupying. These two coral species are also used as a home by symbiotic sipunculans of the genus Aspidosiphon, which normally occupy the corals that were previously occupied by crabs.
Pagurus forbesii is a species of hermit crab in the family Paguridae. It is found in the northeastern Atlantic Ocean and the Mediterranean Sea.
Calcinus morgani, commonly known as Morgan's hermit crab, is a species of hermit crab in the family Diogenidae found in the Indo-West Pacific region, the type locality being Indonesia.
