Hermit Crabs

Paguroidea

Classification

Phylum: Arthropoda
Subphylum: Crustacea
Class: Malacostraca
Superorder: Eucarida
Order: Decapoda
Infraorder: Anomura
Superfamily: Paguroidea

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

Coenobita clypeatus hidden by ZooFari. Used under a Public domain license.

Coenobita clypeatus 202123190 by Donald Davesne. Used under a CC BY 4.0 license.

Clibanarius vittatus-dorsal by Peterwchen. Used under a CC BY-SA 4.0 license.

Coenobita clypeatus by Grook Da Oger. Used under a Public domain license.

Giant Hermit Crab (11670683275) by FWC Fish and Wildlife Research Institute. Used under a CC BY 2.0 license.

Cryptolithodes sitchensis close ventral view by Matt Muir. Used under a CC BY 4.0 license.

Summary

Hermit crabs are anomuran decapod crustaceans of the superfamily Paguroidea, known for their adaptive use of empty shells for protection. They exhibit a diverse range of behaviors and have various symbiotic relationships with other marine organisms.

Physical Characteristics

Hermit crabs have long, spirally curved abdomens which are soft, unlike the hard, calcified abdomens seen in related crustaceans. Their vulnerable abdomen is protected by a salvaged empty seashell, which they can retreat into.

Identification Tips

Most hermit crabs possess an asymmetric abdomen concealed by a snug-fitting shell, often a spiral or coiled snail shell.

Habitat

Hermit crabs are found in almost all marine environments, with many species also inhabiting terrestrial areas in tropical regions.

Distribution

Over 850 species of hermit crabs are found worldwide, often in coastal regions, reefs, and deep-sea environments.

Diet

Hermit crabs are omnivorous scavengers, feeding on detritus, algae, and organic material found in their environment.

Life Cycle

Development involves metamorphosis from symmetric, free-swimming larvae to morphologically asymmetric, benthic-dwelling crabs seeking shells.

Reproduction

Sexual behavior varies; females signal readiness by moult and both sexes may mate multiple times. Eggs are carried on the pleopods of the female.

Predators

Hermit crabs are preyed upon by various animals, including fish, birds, and larger crustaceans.

Ecosystem Role

Hermit crabs play an important role in their ecosystems by recycling nutrients as scavengers and supporting a diverse community of associates and parasites.

Economic Impact

Some marine hermit crabs are popular in the aquarium trade; certain terrestrial species are kept as pets.

Cultural Significance

Hermit crabs, particularly the terrestrial species, are often viewed as pets and enjoyed for their unique behaviors and quirky characteristics.

Collecting Methods

Hand collecting in tidal zones and reefs
Trapping with baited devices

Preservation Methods

Freezing
Drying
Fixation in formaldehyde
Ethanol preservation

Evolution

Paguroidea evolved from ancestral crustaceans, with their reliance on shells exemplifying a significant evolutionary adaptation. They are closely related to squat lobsters and porcelain crabs in the infraorder Anomura.

Similar Taxa

Squat lobsters (family Chirostylidae)
Porcelain crabs (family Porcellanidae)

Misconceptions

Hermit crabs are often thought of as stagnant or low-maintenance pets, but they require specific care and habitat conditions to thrive.