Paguroidea
Latreille, 1802
hermit crabs
Family Guides
4- Coenobitidae(Land Hermit Crabs)
- Diogenidae(Left-handed Hermit Crabs)
- Lithodidae(King Crabs)
- Paguridae(Pagurid Hermit Crabs)
Paguroidea is a superfamily of decapod crustaceans comprising approximately 1100 commonly known as hermit crabs. Members are characterized by a soft, asymmetrical adapted to occupy empty gastropod shells or, in specialized lineages, symbiotic relationships with sea anemones that form protective 'blankets' or 'carcinoecia'. The superfamily exhibits remarkable diversity in shell-use strategies, from traditional gastropod shells to bivalve shells and anemone-derived structures. Distributed across marine environments from intertidal zones to deep-sea , with some lineages having colonized terrestrial .
Pronunciation
How to pronounce Paguroidea: //pæɡjʊˈrɔɪdiə//
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Images
Habitat
Marine environments ranging from intertidal zones to abyssal depths (30–1125 m recorded); includes submarine caves, coral reefs, rocky substrates, and soft sediments. Some lineages inhabit terrestrial coastal forests.
Distribution
Global oceans; particularly diverse in tropical and subtropical Indo-West Pacific. Specific records include: South Africa (West Coast, 199–277 m), Caribbean (Bonaire), southwestern Japan (Ryukyu Islands), Brazil (intertidal to deep waters), and southern California (fossil Pliocene record).
Host Associations
- gastropod shells - Traditional shell occupation; spirally curved to fit gastropod architecture
- sea anemones - mutualismBlanket-hermit crabs (Paguropsis, Paguropsina, Parapaguridae) use specialized chelipeds to manipulate anemone tissue as protective covering; anemone grows with crab, forming non-calcified 'carcinoecia'
- bivalve shells - Porcellanopagurus inhabit bivalve or patelliform shells, secured by uropodal rasps and hydrostatic pressure
- moray eels - commensalism?Pylopaguropsis mollymullerae observed in crevices shared with moray eels; possible cleaning or den commensalism suggested but unconfirmed
Life Cycle
Larval development includes planktonic zoeal stages followed by glaucothoe (post-larval) stage before settlement. Parapagurid hermit crabs begin life in tiny gastropod shells, later transitioning to anemone-derived carcinoecia as they grow.
Behavior
Shell acquisition involves assessment of shell adequacy and active switching . Blanket-hermit crabs use fourth pereiopod chelipeds—modified into bear-claw or ice-tong shapes—to grasp and stretch anemone tissue over their bodies. Some exhibit in cheliped size, with males developing enlarged right chelipeds.
Human Relevance
Subject to fisheries in some regions ( Lithodidae). Popular in aquarium trade. Scientific interest in symbiotic associations and evolutionary adaptations to shell use.
Similar Taxa
- Galatheoidea (squat lobsters)Both within Anomura; squat lobsters have dorsoventrally flattened bodies and typically occupy crevices rather than portable shelters, lacking the asymmetrical and shell-carrying of Paguroidea
- Hippoidea (sand crabs/mole crabs)Both within Anomura; sand crabs have , compact bodies adapted for burrowing in sand, with reduced and no shell association, contrasting with Paguroidea's prominent abdomen and shell dependence
Sources and further reading
- BugGuide
- iNaturalist taxon
- NCBI Taxonomy
- Catalogue of Life
- Five new blanket-hermit crab species described 130 years later from the Pacific | Blog
- hermit crab | Blog
- Neurobiology of the Anomura: Paguroidea, Galatheoidea and Hippoidea
- Hermit crabs from Brazil. Family Paguridae (Crustacea: Decapoda: Paguroidea): Genus Pagurus
- Pliocene hermit crabs (Decapoda, Anomura, Paguroidea) preserved in situ in host gastropod shells from the San Diego Formation near San Diego (southern California, USA)
- Review of the family Lithodidae (Crustacea: Anomura: Paguroidea): Distribution, biology, and fisheries
- Submarine cave hermit crabs (Crustacea: Decapoda: Anomura: Paguroidea) from three islands of the Ryukyu Islands, southwestern Japan
- The shell-acquisition behaviour of the bivalve-using hermit crab Porcellanopagurus nihonkaiensis Takeda, 1985 (Decapoda, Anomura, Paguroidea)
- Based on Mitochondrial Genomes and Gene Order Rearrangements: Phylogenetic Relationships and Terrestrial Adaptability in Paguroidea (Crustacea: Decapoda).