Heterotremata
Encyclopedia
Heterotremata is a clade
of crab
s, comprising those crabs in which the genital openings are on the sternum
in females, but on the legs
in males. It comprises 68 families in 28 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...
in females, but 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 males. It comprises 68 families in 28 superfamilies.
Superfamilies
- AethroideaAethridaeAethridae is a family of crabs in its own superfamily, Aethroidea. It contains the following genera :*Actaeomorpha Miers, 1877*Aethra Latreille in Cuvier, 1816*Drachiella Guinot, in Serene & Soh, 1976...
- BellioideaBelliidaeBelliidae is a family of crabs of the order Decapoda.-Species:Seven species belong to the family Belliidae :*Acanthocyclus albatrossis Rathbun, 1898*Acanthocyclus gayi Lucas, 1844*Acanthocyclus hassleri Rathbun, 1898...
- BythograeoideaBythograeidaeBythograeidae is a small family of crabs which live around hydrothermal vents. The family contains 14 species in 6 genera. Their relationships to other crabs are unclear...
- CalappoideaCalappoideaCalappoidea is a superfamily of crabs comprising the two families Calappidae and Matutidae. The earliest fossils attributable to the Callpoidea date from the Aptian....
- CancroideaCancroideaCancroidea is a superfamily of crabs, comprising the families Atelecyclidae and Cancridae. Two families previously included in this superfamily have since been separated off into new superfamilies – Cheiragonidae into Cheiragonoidea, Corystidae into Corystoidea – while two others have been...
- Carpilioidea
- Cheiragonoidea
- CorystoideaCorystidaeCorystidae is a family of crabs, in its own superfamily, Corystoidea. It includes the oldest Eubrachyuran fossil, Hebertides jurassica, dating from the Bathonian...
- DairoideaDairoideaDairoidea is a superfamily of crabs, comprising two families which each contain a single genus: Dairidae and Dacryopilumnidae .-Species:Dairidae*Daira americana Stimpson, 1860...
- DorippoideaDorippoideaDorippoidea is a superfamily of crabs. The earliest fossils attributable to the Dorippoidea date from the Late Cretaceous....
- EriphioideaEriphioideaEriphioidea is a superfamily of crabs, containing the six families Dairoididae, Eriphiidae, Hypothalassiidae, Menippidae, Oziidae and Platyxanthidae. They are united by a number of characters, including a marked difference in size between the left and right claws, where the larger one has a...
- GecarcinucoideaGecarcinucoideaGecarcinucoidea is a superfamily of freshwater crabs. Its members have been grouped into families in various ways, with some authors recognising families such as "Deckeniidae", "Sundathelphusidae", but only two families are currently recognised: Gecarcinucidae and Parathelphusidae....
- GoneplacoideaGoneplacoideaGoneplacoidea is a superfamily of crabs containing 10 extant families, and two families known only from fossils....
- HexapodoideaHexapodidaeHexapodidae is a family of crabs, the only family in the superfamily Hexapodoidea. It has traditionally been treated as a subfamily of the family Goneplacidae, and was originally described as a subfamily of Pinnotheridae...
- LeucosioideaLeucosioideaLeucosioidea is a superfamily of crabs containing the two families Leucosiidae and Iphiculidae....
- MajoideaMajoideaMajoidea is a superfamily of crabs. It comprises six families:*Epialtidae*Hymenosomatidae*Inachidae*Inachoididae*Majidae*OregoniidaeThe families "Pisidae" and "Tychidae" are now treated as the subfamilies Pisinae and Tychinae of the family Epialtidae, and "Mithracidae" is now treated as the...
- Orithyioidea
- PalicoideaPalicoideaPalicoidea is a superfamily of crabs, comprising the two families Crossotonotidae and Palicidae. Together, they contain 13 genera, including two genera in the Palicidae known only from fossils. The two families were previously treated as two subfamilies in a Palicidae of wider...
- Parthenopoidea
- PilumnoideaPilumnoideaPilumnoidea is a superfamily of crabs, whose members were previously included in the Xanthoidea. The three families are unified by the free articulation of all the segments of the male crab's abdomen and by the form of the gonopods...
- PortunoideaPortunoideaPortunoidea is a superfamily of crabs that includes the family Portunidae, the swimming crabs. Which other crab families are also placed here is a matter of some contention, and may be revised following molecular phylogenetic analyses.-Description:...
- PotamoideaPotamoideaPotamoidea is a superfamily of freshwater crabs, comprising the two families Potamidae and Potamonautidae. Two previously recognised families, Deckeniidae and Platythelphusidae, are now treated as parts of the family Potamonautidae....
- PseudothelphusoideaPseudothelphusidaePseudothelphusidae is a family of freshwater crabs found chiefly in mountain streams in the Neotropics. They are believed to have originated in the Greater Antilles and then crossed to Central America via a Pliocene land bridge.-Parasitology:...
- PseudozioideaPseudozioideaPseudozioidea is a superfamily of crabs, formerly treated in the Eriphioidea, Carpilioidea, Xanthoidea, Pilumnoidea and Goneplacoidea. A number of fossils from the Eocene onwards are known from the family Pseudoziidae...
- RetroplumoideaRetroplumidaeRetroplumidae is a family of heterotrematan crabs, placed in their own superfamily, Retroplumoidea.-Classification:Eight genera are recognised, of which all but two are only known from fossils:*Archaeopus † Rathbun, 1908...
- TrapezioideaTrapezioideaTrapezioidea is a superfamily of crabs. Its members live symbiotically with corals, and have a fossil record stretching back to the Eocene ....
- Trichodactyloidea
- XanthoideaXanthoideaXanthoidea is a superfamily of crabs, comprising the three families Xanthidae, Panopeidae and Pseudorhombilidae. Formerly, a number of other families were included in Xanthoidea, but many of these have since been removed to other superfamilies. These include Carpilioidea, Eriphioidea, Hexapodoidea,...