Portal:Crustaceans

From Wikipedia, the free encyclopedia
Jump to: navigation, search

The crustaceans portal

Abludomelita obtusata.jpg

Crustaceans (Subphylum Crustacea) form a very large group of arthropods, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 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 14 ft (4.3 m) and a mass of 44 lb (20 kg). Like other arthropods, crustaceans have an exoskeleton, which they moult in order 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 the nauplius form of the larvae. Most crustaceans are free-living aquatic animals, but some are terrestrial (e.g. woodlice), some are parasitic (e.g. fish lice, tongue worms) and some are sessile (e.g. barnacles). The group has an extensive fossil record, reaching back to the Cambrian, and includes living fossils such as Triops cancriformis, which has existed apparently unchanged since the Triassic period. More than 10 million tons of crustaceans are produced by fishery or farming for human consumption, the majority of it being shrimps 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.

Selected article

Metanephrops challengeri (Decapoda, Nephropidae)
Metanephrops challengeri (commonly known as the New Zealand lobster or New Zealand scampi) is a species of slim, pink lobster that lives around the coast of New Zealand. It is typically 13–18 cm (5–7 in) long and weighs around 100 g (3.5 oz). The carapace and abdomen are smooth, and adults are white with pink and brown markings and a conspicuous pair of long, slim claws. M. challengeri lives in burrows at depths of 140–640 m (460–2,100 ft) in a variety of sediments. Although individuals can live for up to 15 years, the species shows low fecundity, where small numbers of larvae hatch at an advanced stage.

M. challengeri is a significant prey item for ling, as well as being an important fishery species for human consumption; trawlers catch around 1,000 t (2,200,000 lb) per year under the limitations of New Zealand's Quota Management System. The species was first collected by the Challenger expedition of 1872–1876, but only described as separate from related species by Heinrich Balss in 1914. Although originally classified in the genus Nephrops, it was moved in 1972 to a new genus, Metanephrops, along with most other species then classified in Nephrops.

Did you know?

A hermit crab in a brown snail shell, on a seaweed-covered rock

Selected biography

Edward J. Miers F.Z.S. F.L.S. (1851–1930) was a British zoologist and curator of the crustacean collection at the Natural History Museum in London. He contributed to the scientific reports from the Challenger expedition of 1872–1876, and described 32 new genera and at least 260 new species and subspecies of decapod crustaceans, along with four genera and 72 new species in other orders.

Miers published his Catalogue of the stalk- and sessile-eyed Crustacea of New Zealand in 1876 and revised the Plagusiinae, Hippidae, Majidae, Squillidae and Idoteidae in monographs dated 1878–1881. He also reported on the collections donated by the Admiralty from a number of voyages, including the survey of the coast of Japan by H.M.S. Sylvia (1870–1877), an expedition to view the Transit of Venus in Kerguelen and Rodrigues (1874–1875), a survey of the Galápagos Islands by H.M.S. Petrel, Novaya Zemlya by H.M.S. Isbjorn (1879), Baron Hermann-Maltzan's voyage to Gorée in 1881, and the voyages of H.M.S. Alert to Patagonia and the Strait of Magellan (1881–1882). The upheavals at his workplace and the quantity of work to be done may have taken their toll on Miers, and he was "completely prostrated with illness" for three months.

Miers was still working on material from the Alert expedition, when six boxes containing the crabs from the Challenger expedition arrived, sent by John Murray. Describing these crabs would be Miers' largest taxonomic work, one which was published in 1886 as Report on the Brachyura collected by H. M. S. Challenger during the years 1873–1876 in 1886. Miers' honorarium for this work was £63 (60 guineas).

Associated Wikimedia

Purge server cache