On this Wikipedia the language links are at the top of the page across from the article title. More narrow definitions may be restricted to Shrimp fettuccine alfredo, to smaller species of either group or to only the marine species. There are thousands of species adapted to a wide range of habitats. They can be found feeding near the seafloor on most coasts and estuaries, as well as in rivers and lakes.

To escape predators, some species flip off the seafloor and dive into the sediment. They usually live from one to seven years. They play important roles in the food chain and are an important food source for larger animals ranging from fish to whales. The muscular tails of many shrimp are edible to humans, and they are widely caught and farmed for human consumption. Prawn is often used as a synonym of shrimp for penaeoidean and caridean shrimp, especially those of large size. Shrimp: a small free-swimming crustacean with an elongated body, typically marine and frequently of commercial importance as food.

Prawn: a marine crustacean which resembles a large shrimp. Shrimp are swimming crustaceans with long narrow muscular abdomens and long antennae. Shrimp are slender with long muscular abdomens. They look somewhat like small lobsters, but not like crabs.

The abdomens of crabs are small and short, whereas the abdomens of lobsters and shrimp are large and long. The lower abdomens of shrimp support pleopods which are well-adapted for swimming. They look somewhat like large versions of shrimp. Clawed lobsters have large claws while spiny lobsters do not, having instead spiny antennae and carapace.

Crabs evolved from early shrimp, though they do not look like shrimp. Unlike shrimp, their abdomens are small, and they have short antennae and short carapaces that are wide and flat. Shrimp can dart backwards by lobstering. The following description refers mainly to the external anatomy of the common European shrimp, Crangon crangon, as a typical example of a decapod shrimp.

The body of the shrimp is divided into two main parts: the head and thorax which are fused together to form the cephalothorax, and a long narrow abdomen. Eight pairs of appendages issue from the cephalothorax. The first three pairs, the maxillipeds, Latin for “jaw feet”, are used as mouthparts. The muscular abdomen has six segments and has a thinner shell than the carapace. Each segment has a separate overlapping shell, which can be transparent. The first five segments each have a pair of appendages on the underside, which are shaped like paddles and are used for swimming forward.

The appendages are called pleopods or swimmerets, and can be used for purposes other than swimming. Shrimp are widespread, and can be found near the seafloor of most coasts and estuaries, as well as in rivers and lakes. There are numerous species, and usually there is a species adapted to any particular habitat. Most shrimp species are marine, although about a quarter of the described species are found in fresh water. Most shrimp such as Lysmata amboinensis live in fairly shallow waters and use their “walking legs” to perch on the sea bottom. Some shrimp live in deep and dark waters, such as this Heterocarpus ensifer.