Land crab - AbsoluteAstronomy.com

Gecarcinidae is a family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

of true crab

Crab

True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...

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

Gill

A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...

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

Vertebrate

Vertebrates are animals that are members of the subphylum Vertebrata . Vertebrates are the largest group of chordates, with currently about 58,000 species described. Vertebrates include the jawless fishes, bony fishes, sharks and rays, amphibians, reptiles, mammals, and birds...

lung

Lung

The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...

s. Adult land crabs are terrestrial

Terrestrial animal

Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...

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

Larva

A larva 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...

e develop. Land crabs are tropical omnivore

Omnivore

Omnivores are species that eat both plants and animals as their primary food source...

s which sometimes cause considerable damage to crops. Most land crabs have one of their claws larger than the other.

The family contains the following genera:

Cardisoma
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...
Discoplax
Discoplax
Discoplax is a genus of terrestrial crabs. It is very closely related to the genus Cardisoma.Four species are currently recognised:*Discoplax gracilipes Ng & Guinot, 2001*Discoplax hirtipes...
Epigrapsus
Epigrapsus
Epigrapsus is genus of terrestrial crabs. The three species are omnivores.* Epigrapsus notatus * Epigrapsus politus Heller, 1862* Epigrapsus villosus Ng, 2002...
Gecarcinus
Gecarcinus
Gecarcinus is the type genus of the land crab family Gecarcinidae. They are found in warmer coastal regions of the Americas, including islands in the Caribbean. Four species from oceanic islands were formerly included in Gecarcinus as the subgenus Johngarthia, but are now treated as a separate...
Gecarcoidea
Gecarcoidea
Gecarcoidea is genus of terrestrial crabs. The crabs live in forests but must come to the coast to breed. When it is dry in the summer the crabs are inactive, but when it is the wet season they are ready to migrate.Two species are recognised:...
Johngarthia
Johngarthia
Johngarthia is a genus of crabs in the land crab family Gecarcinidae, formerly included in the genus Gecarcinus, and containing the following five species:...

See also