crayfish

Large crayfish. The crayfish is a ten-limbed crustacean closely related to the lobster family. There are more than 500 species, nearly all of which live in fresh water. The Austropotamobius genus, the most common in Europe, is the only one native to Great Britain.

Freshwater decapod (ten-limbed) crustacean belonging to several families structurally similar to, but smaller than, the lobster. Crayfish are brownish-green scavengers and are found in all parts of the world except Africa. They are edible, and some species are farmed. There are 300–400 species worldwide.

The spiny lobster Palinurus vulgaris, is sometimes called crayfish; it is actually a marine lobster without pincers, and grows up to 50 cm/20 in long.

Two new species were discovered in 1995 in the limestone streams of the Highland Rim, Tennessee. Cambarus williami is very rare and appears to exist in only one small stream; Orconectes durelli is more widespread.