Shrimp, along with crabs, lobsters and crayfish, are among the kinds of invertebrates called decapods (ten feet) that are included in the class Crustacea. There are about 8,500 species of decapods, including 2,000 species of shrimp, in the marine and freshwaters of the world.
Among the decapod crustaceans, penaeids constitute a distinct group of commercially important species. Due to their nutritional value, they support a very valuable, trade export market. Most of these species come under 5 penaeidean families viz., Solenoceridae, Aristidae, Penaeidae, Sicyoniidae and Sergestidae, and three caridian families viz, Pandalidae, Crangonidae and Palaemonidae. The family Palaemonidae includes two subfamilies, namely Palaemoninae and Pontoniinae.
True shrimp are small, swimming, decapod crustaceans classified in the infraorder Caridea, found widely around the world in both fresh and salt water. Shrimp body is almost always laterally compressed, the rostrum usually compressed and toothed, and the abdomen long, longer than the carapace or head. The antennules, or first pair of feelers, in most species bear a small scale or spine, the stylocerite, at their bases. The antennal scales of the second pair of feelers, the antennae, are generally large and plate-like.
Shrimp: The most commonly consumed shellfish
