Portunoidea

Last updated

Portunoidea
Portumnus latipes 1.jpg
Portumnus latipes of the Portunidae
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Crustacea
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
Infraorder: Brachyura
Subsection: Heterotremata
Superfamily: Portunoidea
Rafinesque, 1815
Families [1]

7 extant and 4 extinct families: see text

Portunoidea 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. [1]

Contents

Description

Their rather flat and smooth carapace is usually wider than long and of hexagonal, subhexagonal, rectangular, or transversely ovate shape. It is usually widest between the hindmost spines of the forward rim; there may be up to 9 pairs of these spines, with a few smaller ones right above the head, but they are missing altogether in some species. [2]

In some, the first maxilliped's endopod is lobed, forming the characteristic portunid lobe. The chelipeds are usually robust, and in some the last pereiopod pair has ovate dactyls. The sutures of the sternum between segments 4 to 8 are usually incomplete, and in the Portunidae, the eighth sternite is usually visible if seen from below and has a penial groove. [2]

In males, the abdominal somites are either all free or the third to fifth are fused, often retaining the sutures though. The first gonopod is strongly curved, with a swollen and strongly hooked base. [2]

Classification

Representative putative symbiotic Thalamitinae species Portunoidea (10.7717-peerj.4260) Figure 3.png
Representative putative symbiotic Thalamitinae species

Portunoidea are close relatives of the Xanthoidea, [2] and the families Hexapodidae and Mathildellidae, usually included there, are sometimes placed in the Portunoidea, while the deep-sea crabs (Geryonidae) are usually placed in the Portunoidea but sometimes in the Xanthoidea. All Portunoidea live in the ocean, although the family Trichodactylidae, sometimes included here, live in fresh water.

According to the latest synopsis, there are eleven families in the superfamily Portunoidea, four of which are extinct: [1]

Related Research Articles

<span class="mw-page-title-main">Tetraodontiformes</span> Order of fishes

The Tetraodontiformes are an order of highly derived ray-finned fish, also called the Plectognathi. Sometimes these are classified as a suborder of the order Perciformes. The Tetraodontiformes are represented by 10 extant families and at least 349 species overall; most are marine and dwell in and around tropical coral reefs, but a few species are found in freshwater streams and estuaries. They have no close relatives, and descend from a line of coral-dwelling species that emerged around 80 million years ago.

<span class="mw-page-title-main">Crab</span> Infraorder of decapod crustaceans

Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen), usually hidden entirely under the thorax. They live in all the world's oceans, in freshwater, and on land, are generally covered with a thick exoskeleton, and have a single pair of pincers. They first appeared during the Jurassic Period.

<span class="mw-page-title-main">Aulopiformes</span> Order of fishes

Aulopiformes is a diverse order of marine ray-finned fish consisting of some 15 extant and several prehistoric families with about 45 genera and over 230 species. The common names grinners, lizardfishes and allies, or aulopiforms are sometimes used for this group. The scientific name means "Aulopus-shaped", from Aulopus + the standard fish order suffix "-formes". It ultimately derives from Ancient Greek aulós + Latin forma, the former in reference to the elongated shape of many aulopiforms.

<span class="mw-page-title-main">Elachistidae</span> Family of moths

The Elachistidae are a family of small moths in the superfamily Gelechioidea. Some authors lump about 3,300 species in eight subfamilies here, but this arrangement almost certainly results in a massively paraphyletic and completely unnatural assemblage, united merely by symplesiomorphies retained from the first gelechioid moths.

<span class="mw-page-title-main">Nautiloid</span> Extant subclass of cephalopods

Nautiloids are a group of marine cephalopods (Mollusca) which originated in the Late Cambrian and are represented today by the living Nautilus and Allonautilus. Fossil nautiloids are diverse and speciose, with over 2,500 recorded species. They flourished during the early Paleozoic era, when they constituted the main predatory animals. Early in their evolution, nautiloids developed an extraordinary diversity of shell shapes, including coiled morphologies and giant straight-shelled forms (orthocones). Only a handful of rare coiled species, the nautiluses, survive to the present day.

<span class="mw-page-title-main">Xiphosura</span> Order of marine chelicerates

Xiphosura is an order of arthropods related to arachnids. They are more commonly known as horseshoe crabs. They first appeared in the Hirnantian. Currently, there are only four living species. Xiphosura contains one suborder, Xiphosurida, and several stem-genera.

<span class="mw-page-title-main">Staphyliniformia</span> Infraorder of beetles

Staphyliniformia is a large infraorder of beetles. It contains over 70,000 described species from all regions of the world. Most species occur in moist habitats - various kinds of rotting plant debris, fungi, dung, carrion, many live in fresh water.

<span class="mw-page-title-main">Anomura</span> Infraorder of crustaceans

Anomura is a group of decapod crustaceans, including hermit crabs and others. Although the names of many anomurans include the word crab, all true crabs are in the sister group to the Anomura, the Brachyura.

<span class="mw-page-title-main">Portunidae</span> Family of crabs

Portunidae is a family of crabs which contains the swimming crabs.

<span class="mw-page-title-main">Ocypodidae</span> Family of crabs

The Ocypodidae are a family of semiterrestrial crabs that includes the ghost crabs and fiddler crabs. They are found on tropical and temperate shorelines around the world.

<span class="mw-page-title-main">Xanthoidea</span> Superfamily of crabs

Xanthoidea 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, Pilumnoidea and Trapezioidea. Even in this reduced state, Xanthoidea remains one of the most species-rich superfamilies of crabs.

Carcineretidae is a prehistoric family of heterotrematan crustaceans. They are only known from Cretaceous fossils. These crabs are tentatively placed in the superfamily Portunoidea and resemble the swimming crabs (Portunidae) in having some paddle-shaped pereiopods. But it is not certain that this placement is correct, as the Carcineretidae also show some similarities to the Matutidae of superfamily Leucosioidea and the Goneplacidae of superfamily Xanthoidea.

<span class="mw-page-title-main">Limacoidei</span> Group of molluscs

The Limacoidei is a taxonomic infraorder of air-breathing land snails, semislugs and slugs, terrestrial pulmonate gastropod molluscs in the suborder Helicina

<span class="mw-page-title-main">Batillariidae</span> Family of gastropods

Batillariidae, common name batillariids or mudcreepers, are a family of marine, cerithioidean gastropod molluscs in thesuperfamily Cerithioidea.

<span class="mw-page-title-main">Heterotremata</span> Clade of crabs

Heterotremata is a clade of crabs, 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.

<i>Actumnus</i> Genus of crabs

Actumnus is a genus of crabs in the family Pilumnidae. Alongside the 28 extant species, it has a fossil record extending back into the Miocene.

<span class="mw-page-title-main">Matutidae</span> Family of crabs

Matutidae is a family of crabs, sometimes called moon crabs, adapted for swimming or digging. They differ from the swimming crabs of the family Portunidae in that all five pairs of legs are flattened, rather than just the last pair, as in Portunidae. Crabs in the Matutidae are aggressive predators.

<span class="mw-page-title-main">Pseudozioidea</span> Superfamily of crabs

Pseudozioidea 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. Eleven genera are recognised in three families:

<span class="mw-page-title-main">Crustacean larva</span> Crustacean larval and immature stages between hatching and adult form

Crustaceans may pass through a number of larval and immature stages between hatching from their eggs and reaching their adult form. Each of the stages is separated by a moult, in which the hard exoskeleton is shed to allow the animal to grow. The larvae of crustaceans often bear little resemblance to the adult, and there are still cases where it is not known what larvae will grow into what adults. This is especially true of crustaceans which live as benthic adults, more-so than where the larvae are planktonic, and thereby easily caught.

<span class="mw-page-title-main">Chyphotidae</span> Family of wasps

The Chyphotidae are a family of wasps similar to the Mutillidae, differing most visibly in the presence, in females, of a suture separating the pronotum from the mesonotum. These species are found primarily in arid regions in the southwestern United States and adjacent regions in Mexico.

References

  1. 1 2 3 Sammy De Grave; N. Dean Pentcheff; Shane T. Ahyong; et al. (2009). "A classification of living and fossil genera of decapod crustaceans" (PDF). Raffles Bulletin of Zoology . Suppl. 21: 1–109.
  2. 1 2 3 4 Hiroaki Karasawa & Carrie E. Schweitzer (2006). "A new classification of the Xanthoidea sensu lato (Crustacea: Decapoda: Brachyura) based on phylogenetic analysis and traditional systematics and evaluation of all fossil Xanthoidea sensu lato". Contributions to Zoology . 75 (1/2): 23–73. Archived from the original on 2016-03-03. Retrieved 2008-11-23.

Commons-logo.svg Media related to Portunoidea at Wikimedia Commons