The Gecarcinidae, the land crabs, are a

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

of true

crab Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( el, βραχύς , translit=brachys = short, / = tail), usually hidden entirely under the thorax. They live in all the ...

s that are adapted for terrestrial existence. Similar to all other crabs, land crabs possess a series of

gill A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

s. In addition, the part of the carapace covering the gills is inflated and equipped with blood vessels. These organs extract oxygen from the air, analogous to the

vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...

lung The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of t ...

s. Adult land crabs are

terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...

, but visit the sea periodically, where they breed and their

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

e develop. Land crabs are tropical

omnivore An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nutr ...

s which sometimes cause considerable damage to crops. Most land crabs have one of their claws larger than the other. The family contains these genera: * ''

Cardisoma ''Cardisoma'' is a genus of large land crabs. Three species formerly placed in this genus are now placed in '' Discoplax''. The four species that remain in ''Cardisoma'' are found in warm coastal regions where they live in burrows. Young individu ...

'' * '' Discoplax'' * '' Epigrapsus'' * '' Gecarcinus'' * '' Gecarcoidea'' * '' Johngarthia'' * ''

Tuerkayana ''Tuerkayana'' is a genus of large land crabs. It was created from two members of the genus ''Cardisoma'' and two members of '' Discoplax'' in late 2018 after a re-examination of the taxonomy of the family Gecarcinidae. Said re-examination also ...

References

*Encarta Reference Library Premium 2005 DVD.

External links

* * Grapsoidea Decapod families {{crab-stub

See also

References

External links