Crustacean
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A Crustacean is an anrthropod (with a exoskeleton that is moulted) with biramous (two-parted) limbs and larval forms, such as the nauplius stage of branchiopods and copepods.
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- See: Grapsus Grapsus, Homarus Gammarus, Procambarus Clarkii, Lysmata Amboinensis, Euphausia Superba, Hemilepistus Reaumuri, Calanoida, Lepas Anatifera, Thylacocephala.
References
2022
- (Wikipedia, 2022) ⇒ https://en.wikipedia.org/wiki/Crustacean Retrieved:2022-1-19.
- Crustaceans (Crustacea ) form a large, diverse arthropod taxon which includes such animals as crabs, lobsters, crayfish, shrimp, krill, prawns, woodlice, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata; because of recent molecular studies it is now well accepted that the crustacean group is paraphyletic, and comprises all animals in the clade Pancrustacea other than hexapods. Some crustaceans (Remipedia, Cephalocarida, Malacostraca) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span of up to and a mass of . 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), 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 produced by fishery or farming for human consumption, most of it being 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.