goglis.blogg.se - Crayfish clawfish

In New Zealand, two species of Paranephrops are endemic, and are known by the Māori name kōura. tenuimanus is critically endangered, while other large Australasian crayfish are threatened or endangered. Many of the better-known Australian crayfish are of the genus Cherax, and include the common yabby ( C.

the marron from Western Australia (now believed to be two species, Cherax tenuimanus and C.

It is found in much of the southern Murray-Darling basin.

the Murray crayfish Euastacus armatus, which can reach 2.5 kg (5.5 lb), although reports of animals up to 3 kg (6.6 lb) have been made.

the Tasmanian giant freshwater crayfish Astacopsis gouldi, which can achieve a mass over 5 kg (11 lb) and is found in rivers of northern Tasmania.

It is home to the world's three largest freshwater crayfish: Australia Īustralia has over 100 species in a dozen genera. Their products include crawfish attached to wooden plaques, T-shirts with crawfish logos, and crawfish pendants, earrings, and necklaces made of gold or silver. A variety of cottage industries have developed as a result of commercialized crawfish iconography.

Crawfish are a part of Cajun culture dating back hundreds of years. Louisiana produces 100 million pounds (45 million kilograms) of crawfish per year with the red swamp and white river crawfish being the main species harvested. In 1983, Louisiana designated the crayfish, or crawfish as they are commonly called, as its official state crustacean. Many crayfish are also found in lowland areas where the water is abundant in calcium, and oxygen rises from underground springs. A further genus of astacid crayfish is found in the Pacific Northwest and the headwaters of some rivers east of the Continental Divide. The greatest diversity of crayfish species is found in southeastern North America, with over 330 species in 15 genera, all in the family Cambaridae.

Of the other three Northern Hemisphere families (grouped in the superfamily Astacoidea), the four genera of the family Astacidae live in western Eurasia and western North America, the 15 genera of the family Cambaridae live in eastern North America, and the single genus of Cambaroididae live in eastern Asia. They are distinguished by the absence of the first pair of pleopods. The Southern Hemisphere ( Gondwana-distributed) family Parastacidae, with 14 extant genera and two extinct genera, live(d) in South America, Madagascar, and Australasia. Their phylogeny can be shown in the simplified cladogram below: Astacideaįour extant (living) families of crayfish are described, three in the Northern Hemisphere and one in the Southern Hemisphere. Anatomy Ĭrayfish are closely related to lobsters, and together they belong to the infraorder Astacidea.

The study of crayfish is called astacology. In the Eastern United States, "crayfish" is more common in the north, while "crawdad" is heard more in central and southwestern regions, and "crawfish" farther south, although considerable overlaps exist. Some kinds of crayfish are known locally as lobsters, crawdads, mudbugs, and yabbies. The largely American variant "crawfish" is similarly derived. The word has been modified to "crayfish" by association with "fish" ( folk etymology). The name "crayfish" comes from the Old French word escrevisse ( Modern French écrevisse).

3 Classification and geographical distribution.