Thoracotremata
Encyclopedia
Thoracotremata is a clade
of crab
s, comprising those crabs in which the genital openings are on the sternum
, rather than on the legs
in both sexes. It comprises 17 families in four superfamilies .
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
of 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, comprising those crabs in which the genital openings are on the sternum
Sternum (arthropod)
The sternum is the ventral portion of a segment of an arthropod thorax or abdomen.In insects, the sterna are usually single, large sclerites, and external...
, rather than on the legs
Arthropod leg
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments are of Latin origin, and may be confused with terms for bones: coxa , trochanter , femur, tibia, tarsus, ischium, metatarsus, carpus, dactylus ,...
in both sexes. It comprises 17 families in four superfamilies .
Superfamilies and families
- OcypodoideaOcypodoideaOcypodoidea is a superfamily of crabs, named after the genus Ocypode. It contains over 300 extant species in the following eight families:* Camptandriidae Stimpson, 1858* Dotillidae Stimpson, 1858* Heloeciidae H. Milne-Edwards, 1852...
- Camptandriidae
- DotillidaeDotillidaeDotillidae is a family of crabs. It comprises 59 species, nearly half of which are in the genus Ilyoplax. The two genera Scopimera and Dotilla are collectively the sand bubbler crabs, which leave conspicuous collections of sand pellets on sandy beaches across the tropical and sub-tropical...
- Heloeciidae
- Macrophthalmidae
- Mictyridae
- OcypodidaeOcypodidaeOcypodidae is a family of crabs that includes the ghost crabs and fiddler crabs. Other genera previously included in the family are now treated as members of separate families in the superfamily Ocypodoidea, such as Ucididae, Dotillidae and Macrophthalmidae....
- Ucididae
- Xenophthalmidae
- PinnotheroideaPinnotheridaePinnotheridae is a family of pea crabs. Pea crabs are tiny soft-bodied crabs that live commensally in the mantles of certain bivalve molluscs...
- PinnotheridaePinnotheridaePinnotheridae is a family of pea crabs. Pea crabs are tiny soft-bodied crabs that live commensally in the mantles of certain bivalve molluscs...
- Pinnotheridae
- CryptochiroideaCryptochiridaeCryptochiridae is a family of crabs, known as gall crabs, because the females cause corals to form protective galls around themselves. The family is placed in its own superfamily, Cryptochiroidea...
- CryptochiridaeCryptochiridaeCryptochiridae is a family of crabs, known as gall crabs, because the females cause corals to form protective galls around themselves. The family is placed in its own superfamily, Cryptochiroidea...
- Cryptochiridae
- GrapsoideaGrapsoideaGrapsoidea is a superfamily of crabs. These crabs are well known and contain many taxa which are terrestrial , semi-terrestrial or limnic...
- Gecarcinidae
- Glyptograpsidae
- GrapsidaeGrapsidaeGrapsidae is a family of crabs known variously as marsh crabs, shore crabs or talon crabs. It is not confirmed that the family forms a monophyletic group and some taxa may belong in other families...
- PlagusiidaePlagusiidaePlagusiidae is a family of crabs. It was formerly treated as a subfamily of the family Grapsidae, but has since been considered sufficiently distinct to be a family in its own right.Five genera are included in the family:*Davusia Guinot, 2007...
- SesarmidaeSesarmidaeSesarmidae is a family of crabs, previously included in the Grapsidae by many authors. Several species, namely in Geosesarma, Metopaulias and Sesarma, are true terrestrial crabs. They do not need to return to the sea even for breeding.-Genera:...
- VarunidaeVarunidaeVarunidae is a family of thoracotrematan crabs. The delimitation of this family, part of the taxonomically confusing Grapsoidea, is undergoing revision. For a long time, they were placed at the rank of subfamily in the Grapsidae, but they appear to be closest to Macropthalmus and the Mictyridae,...
- Xenograpsidae