Portal:Crustaceans

Portal topics: Activities; Culture; Geography; Health; History; Mathematics; Nature; People; Philosophy; Religion; Society; Technology; Random portal

The Crustaceans Portal

Crustaceans are a group of arthropods that are a part of the subphylum Crustacea (/krəˈsteɪʃə/), a large, diverse group of mainly aquatic arthropods including decapods (shrimps, prawns, crabs, lobsters and crayfish), seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, opossum shrimps, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods (insects and entognathans) emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. The three classes Cephalocarida, Branchiopoda and Remipedia are more closely related to the hexapods than they are to any of the other crustaceans (oligostracans and multicrustaceans).

The 67,000 described species range in size from Stygotantulus stocki at 0.1 mm (0.004 in), to the Japanese spider crab with a leg span of up to 3.8 m (12.5 ft) and a mass of 20 kg (44 lb). Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by their larval forms, such as the nauplius stage of branchiopods and copepods.

Most crustaceans are free-living aquatic animals, but some are terrestrial (e.g. woodlice, sandhoppers), some are parasitic (e.g. Rhizocephala, fish lice, tongue worms) and some are sessile (e.g. barnacles). The group has an extensive fossil record, reaching back to the Cambrian. More than 7.9 million tons of crustaceans per year are harvested by fishery or farming for human consumption, consisting mostly of shrimp and prawns. Krill and copepods are not as widely fished, but may be the animals with the greatest biomass on the planet, and form a vital part of the food chain. The scientific study of crustaceans is known as carcinology (alternatively, malacostracology, crustaceology or crustalogy), and a scientist who works in carcinology is a carcinologist. (Full article...)

Refresh with new selections below (purge)

Selected article

Scyllarides latus, the Mediterranean slipper lobster, is a species of slipper lobster found in the Mediterranean Sea and in the eastern Atlantic Ocean. It is edible and highly regarded as food, but is now rare over much of its range due to overfishing. Adults may grow to 1 foot (30 cm) long, are camouflaged, and have no claws. They are nocturnal, emerging from caves and other shelters during the night to feed on molluscs. As well as being eaten by humans, S. latus is also preyed upon by a variety of bony fish. Its closest relative is S. herklotsii, which occurs off the Atlantic coast of West Africa; other species of Scyllarides occur in the western Atlantic Ocean and the Indo-Pacific. The larvae and young animals are largely unknown.

Read more...

More selected articles

Did you know?

... that symbiotic moss animals live on setae on the antennae, mouthparts and legs of the crab Goneplax rhomboides (pictured)?
... that Geograpsus severnsi is the first crab species known to have become extinct in historical times?
... that cycloids are believed to have been driven to extinction when crabs spread across their territory?
... that the fairy shrimp Branchinecta brushi lives at 5,930 m (19,460 ft) in the Chilean Andes, higher than any other crustacean in the world?

More Did you know facts

Selected biography

Pierre André Latreille (November 20, 1762 – February 6, 1833) was a French zoologist, specialising in arthropods. Latreille was born illegitimately on November 29, 1762 in the town of Brive, then in the province of Limousin. Having trained as a Roman Catholic priest before the French Revolution, Latreille was imprisoned after the Civil Constitution of the Clergy, and only regained his freedom after recognising a rare species he found in the prison, Necrobia ruficollis.

He published his first important work in 1796 (Précis des caractères génériques des insectes), and was eventually employed by the Muséum National d'Histoire Naturelle. His foresighted work on arthropod systematics and taxonomy, using all available characters and rejecting anthropocentrism and teleology, gained him respect and accolades. He was considered the foremost entomologist of his time, and was described by one of his pupils as "the prince of entomologists". He helped found the Société entomologique de France, acting as honorary president, and was honoured by having dozens of species and genera named after him.

Read more...

More selected biographies

Selected image

Credit: Nick Hobgood

Periclimenes imperator (Decapoda: Palaemonidae) is a species of shrimp with a wide distribution across the Indo-Pacific that lives commensally on a number of hosts, including the sea slug Hexabranchus.

Read more...

More selected pictures

General images

The following are images from various crustacean-related articles on Wikipedia.

Image 1Porcellio scaber and Oniscus asellus (Peracarida: Isopoda) (from Malacostraca)
Image 2Cancer pagurus (Eucarida: Decapoda) (from Malacostraca)
Image 3Leptostraca such as Nebalia bipes retain the primitive condition of having seven abdominal segments. (from Malacostraca)
Image 4Abludomelita obtusata, an amphipod (from Crustacean)
Image 5Daphnia pulex (Cladocera: Daphniidae) (from Branchiopoda)
Image 6Artemia salina (Anostraca: Artemiidae) (from Branchiopoda)
Image 7Odontodactylus scyllarus (Hoplocarida: Stomatopoda) (from Malacostraca)
Image 8A shed carapace of a lady crab, part of the hard exoskeleton
Image 9Ostracod (from Ostracod)
Image 10Articulated ostracod valves in cross-section from the Permian of central Texas; typical thin section view of an ostracod fossil (from Ostracod)
Image 11Squilla empusa,
a mantis shrimp (from Malacostraca)
Image 12Norway lobsters on sale at a Spanish market
Image 13Anatomy of Cypridina mediterranea (from Ostracod)
Image 14Copepods, from Ernst Haeckel's 1904 work Kunstformen der Natur (from Crustacean)
Image 15Zoea larva of the European lobster, Homarus gammarus
Image 16Body structure of a typical crustacean – krill (from Crustacean)
Image 17Eggs of Potamon fluviatile, a freshwater crab
Image 18The large ostracod Herrmannina from the Silurian (Ludlow) Soeginina Beds (Paadla Formation) on eastern Saaremaa Island, Estonia (from Ostracod)
Image 19Eryma mandelslohi, a fossil decapod from the Jurassic of Bissingen an der Teck, Germany
Image 20Ostracod swimming motions (in real time) (from Ostracod)
Image 21Grapsus grapsus, a terrestrial crab (from Malacostraca)
Image 22Decapods, from Ernst Haeckel's 1904 work Kunstformen der Natur (from Crustacean)