Shrimp are swimming crustaceans that feed coasts and markets
Shrimp commonly names elongated, swimming crustaceans—usually caridean or related decapods—though narrow definitions limit the word to Caridea or only marine forms, and broad ones blur into prawn. Thousands of species fill fresh and salt habitats from coasts to estuaries.
Muscular tails make them among the most eaten shellfish; wild catch and farms supply tables worldwide, with estimates of roughly four hundred forty billion farmed shrimp and twenty-five trillion wild shrimp killed yearly. Bottom-feeding lifestyles link mudflats to global menus.
Scientists treat shrimp and prawn as convenience labels rather than real taxa. Crustacean taxonomist Tin-Yam Chan notes that shrimp is sometimes used for smaller species and prawn for larger ones, but usage is muddled and even reversed from region to region. Size alone fails anyway: many shrimp are about 2 centimetres long, yet Penaeus monodon tops 25, which makes jumbo shrimp sound like an oxymoron. The word itself dates to 14th-century Middle English shrimpe, related to Germanic and Norse terms for contracting or shrivelling.
The body follows a shared plan, with head and thorax fused under a thick carapace and a six-segmented abdomen behind. Eight pairs of appendages hang from the front section: three pairs of maxillipeds, or jaw feet, serve as mouthparts, and five pairs of pereiopods make up the ten legs that give decapods their name. The first five abdominal segments carry paddle-like swimmerets, which in some species also brood eggs. About a quarter of described species live in fresh water, and marine ones reach 5,000 metres deep.
Some species escape predators by flicking off the bottom and diving into sediment, and pistol shrimp snap one oversized claw loudly. The fossil record is thin, with only 57 exclusively fossil species, the oldest from the Lower Jurassic.
Source: Shrimp
