| Euastacus spinifer | |
|---|---|
 | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Malacostraca |
| Order: | Decapoda |
| Suborder: | Pleocyemata |
| Family: | Parastacidae |
| Genus: | Euastacus |
| Species: | E. spinifer |
| Binomial name | |
| Euastacus spinifer (Heller, 1865) | |
 | |
| Range of Euastacus spinifer (orange) in Australia | |
Euastacus spinifer is a species of freshwater crayfish endemic to Australia that belongs to the family Parastacidae.
Morphological variation is observed in Euastacus spinifer that originate in different river systems. They are mostly green with reddish-brown joints and bright spines. [2]
Detritus forms the staple diet of the species but they may also eat small invertebrates and tadpoles. [2] They are also cannibalistic. They are also believed to be opportunistic omnivore. [3]
Mating takes place in winter when temperature drops to as low as 15 °C (59 °F), and eggs are laid in early July. Eggs are carried in the female Pleopods and hatch after an incubation period of 110–140 days. Hatch-lings stay with their parents until early summer. Males mature in 5–6 years and grow to 11 centimetres (4 in) on maturity while females take about 8 years and from above 14 centimetres (6 in). There are a class of "precious males" that mature at 4 centimetres (2 in) length. There are slight variation in reproduction cycle between species in different river systems. [4]
Euastacus spinifer may grow up to 24 centimetres (9 in). [2] Largest recorded weight is 1.8 kilograms (4.0 lb). [5]
They are endemic to Australia. They may be found from near sea level to as high as 1,200 metres (3,900 ft). They are distributed over a range of 55,000 square kilometres (21,000 sq mi). [1]
Creeks and estuaries are their usual habitats. Their habitats are usually shaded by vegetation. [6]
Moulting frequency of individuals in the species differ with size smaller individuals moult up to six times a year while larger individuals moult only once. Different sizes moult a different seasons temperature is believed to be the regulating force. [7]
Crayfish are freshwater crustaceans belonging to the infraorder Astacidea, which also contains lobsters. Taxonomically, they are members of the superfamilies Astacoidea and Parastacoidea. They breathe through feather-like gills. Some species are found in brooks and streams, where fresh water is running, while others thrive in swamps, ditches, and paddy fields. Most crayfish cannot tolerate polluted water, although some species, such as Procambarus clarkii, are hardier. Crayfish feed on animals and plants, either living or decomposing, and detritus.
The Parastacidae are the family of freshwater crayfish found in the Southern Hemisphere. The family is a classic Gondwana-distributed taxon, with extant members in South America, Madagascar, Australia, New Zealand, and New Guinea, and extinct taxa also in Antarctica.
Cherax tenuimanus, known as the Hairy marron or Margaret River marron, is one of two species of crayfish in Southwestern Australia known as marron. It occupies a narrow range within the southwestern biogeographical region of Margaret River. It is currently listed as critically endangered on the IUCN Red List, because of the threat from the wider ranged smooth marron, Cherax cainii, which was introduced to its habitat.
Cherax, commonly known as yabby/yabbies in Australia, is the most widespread genus of fully aquatic crayfish in the Southern Hemisphere. Various species of cherax may be found in both still and flowing bodies of freshwater across most of Australia and New Guinea. Together with Euastacus, it is also the largest crayfish genus in the Southern Hemisphere.
The Tasmanian giant freshwater crayfish, also called Tasmanian giant freshwater lobster, is the largest freshwater invertebrate and the largest freshwater crayfish species in the world. The species is only found in the rivers below 400 metres (1,300 ft) above sea level in northern Tasmania, an island-state of Australia. It is listed as an endangered species on the IUCN Red List due to overfishing and habitat degradation, and it has been prohibited to catch the crayfish since 1998.
The Murray crayfish, Euastacus armatus, is a species of freshwater crayfish endemic to Australia that belongs to the family Parastacidae. The Murray crayfish has the largest geographic range of any of the Euastacus crayfish in Australia, being found in the Murray and Murrumbidgee Rivers as well as many of their tributaries. Murray crayfish are also known as "Murray River crayfish", "Murray crays", "freshwater crays", "spiny freshwater crays", "spinies" and in the Wagga Wagga region of southern New South Wales they are simply known as "lobsters".
Euastacus is a genus of freshwater crayfish known as "spiny crayfish". They are found in the south-east of the Australian mainland, along with another genus of crayfish, Cherax. Both genera are members of the family Parastacidae, a family of freshwater crayfish restricted to the Southern Hemisphere.
Cherax quinquecarinatus is a small freshwater crayfish endemic to the south-west corner of Australia. It is one of two species known as gilgie, or jilgi, which is a seasonal food source for people of the region. Gilgies are found throughout a biogeographically isolated region of the coastal south of Western Australia and are significant in the ecology of aquatic systems of that bioregion.
Astacoides is a genus of freshwater crayfish endemic to Madagascar. The first specimens were brought to Europe in 1839, and seven species are now recognised, most of which are considered as threatened on the IUCN Red List. They are large and slow-growing, and are threatened by habitat loss, overexploitation by local people and by spread of introduced non-indigenous marbled crayfish. They are only found in a relatively small part of the island, mostly in undisturbed upland areas. They belong to the Gondwana-distributed family Parastacidae, but their nearest relatives live in Australasia, there being no native crayfish in mainland Africa or India.
Euastacus bispinosus, the Glenelg spiny crayfish, is a species of southern crawfish in the family Parastacidae.
Euastacus crassus is a species of southern crayfish in the family Parastacidae. It is commonly known as the Alpine spiny crayfish.
Euastacus eungella is a species of southern crawfish in the family Parastacidae.
Euastacus fleckeri is a species of southern crawfish in the family Parastacidae.
Euastacus setosus is a species of southern crawfish in the family Parastacidae.
Euastacus urospinosus is a species of southern crawfish in the family Parastacidae.
Astacopsis is a genus of crayfish endemic to the island of Tasmania. There are three extant species, Astacopsis gouldi, Astacopsis franklinii, and Astacopsis tricornis. All are threatened by illegal harvesting, and A. gouldi is protected by law. A. franklinii is found in the eastern half of the island, with A. tricornis taking its place in the west. A. gouldi is found only in rivers draining into the Bass Strait, except for the Tamar River.
Ellen Clark (1915–1988) was an Australian carcinologist and naturalist, whose work focused on crustaceans and ants Clark studied, named, described and published many of the Australian freshwater crayfish species. By 1939, she was reported to have identified more than half the known species of Australian crayfish. She conducted research about blood groups in crustaceans and made a significant contribution to the study of crayfish genera. She was the first woman to publish in the Memoirs of the National Museum of Victoria.
Euastacus dalagarbe is a species of freshwater crayfish endemic to Australia that belongs to the family Parastacidae. It has a small range in New South Wales and is regarded by the International Union for Conservation of Nature as "critically endangered".
Euastacus bidawalus, the East Gippsland spiny crayfish, is an Australian freshwater crayfish endemic to the East Gippsland area of Victoria and the far south coast of New South Wales.
Euastacus yanga, also known as the variable spiny cray, is a freshwater crayfish endemic to south eastern Australia.
