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 spiny 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" and in the Wagga Wagga region of southern New South Wales they are simply known as "lobsters". The conservation status of a species is an indicator of the likelihood of that species continuing to survive. ... Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms (as opposed to folk taxonomy). ... Phyla Subregnum Parazoa Porifera (sponges) Subregnum Agnotozoa Placozoa (trichoplax) Orthonectida (orthonectids) Rhombozoa (dicyemids) Subregnum Eumetazoa Radiata (unranked) (radial symmetry) Ctenophora (comb jellies) Cnidaria (coral, jellyfish, anemones) Bilateria (unranked) (bilateral symmetry) Acoelomorpha (basal) Orthonectida (parasitic to flatworms, echinoderms, etc. ... Subphyla and Classes Subphylum Trilobitomorpha Trilobita - Trilobites (extinct) Subphylum Chelicerata Arachnida - Spiders, Scorpions, etc. ... Classes Remipedia Cephalocarida Branchiopoda Ostracoda Maxillopoda Malacostraca The crustaceans (Crustacea) are a large group of arthropods (55,000 species), usually treated as a subphylum. ... Subclasses Eumalacostraca Hoplocarida Phyllocarida See text for orders. ... Suborders and Infraorders Dendrobranchiata Pleocyemata Caridea Stenopodidea Reptantia, comprising: Eryonoidea Achelata Astacidea Glypheidea Thalassinidea Anomala Brachyura The decapods or Decapoda are a group of crustaceans within the class Malacostraca, including many familiar groups of crustaceans, such as crabs, lobsters and shrimp, but also some families that are less well known. ... Infraorders Caridea Stenopodidea Reptantia, divided into: Polychelida Achelata Glypheoidea Astacidea Thalassinidea Anomala Brachyura Pleocyemata is a sub-order of decapod crustaceans, erected by Martin Burkenroad in 1963. ... Superfamilies see text Astacidea is a group of decapod crustaceans including lobsters, crayfish and their close relatives. ... Genera Astacoides Astacopsis Cherax Engaeus Engaewa Euastacus Geocherax Gramastacus Paranephrops Parastacoides Parastacus Samastacus Tenuibranchiurus Virilastacus Parastacidae is the family of freshwater crayfish found in the southern hemisphere. ... In biology, binomial nomenclature is the formal method of naming species. ... Eduard von Martens (sometimes Carl or Karl Eduard von Martens) was a German zoologist. ... In biology, a species is the basic unit of biodiversity. ... Families Astacoidea   Astacidae   Cambaridae Parastacoidea   Parastacidae Crayfish, sometimes called crawfish, or crawdads are freshwater crustaceans resembling small lobsters, to which they are closely related. ... In biology and ecology endemic means exclusively native to a place or biota, in contrast to cosmopolitan or introduced. ... Genera Astacoides Astacopsis Cherax Engaeus Engaewa Euastacus Geocherax Gramastacus Paranephrops Parastacoides Parastacus Samastacus Tenuibranchiurus Virilastacus Parastacidae is the family of freshwater crayfish found in the southern hemisphere. ... The Murray River, or River Murray, is Australias second-longest river in its own right (the longest being its tributary the Darling). ... The Murrumbidgee River is a major river in the state of New South Wales, Australia. ... Wagga Wagga New South Wales, Australia, lies on the Murrumbidgee River and is that states largest inland city as well as being an important agricultural, military, educational and transport hub. ... Emblems: Floral - Waratah (Telopea Speciosissima); Bird - Kookaburra (Dacelo Gigas); Animal - Platypus (Ornithorhynchus Anatinus); Fish - Blue Groper (Achoerodus Viridis) Motto: Orta Recens Quam Pura Nites (Newly Risen, How Brightly You Shine) Slogan or Nickname: First State, Premier State Other Australian states and territories Capital Sydney Government Governor Premier Const. ...

Adults grow to 20 to 30 cm in length and they have large white claws and an ornately spiked carapace. In small individuals, the claws are green and yellow. The crayfish begin to breed when they are 15 to 20 cm long, which takes between 6 and 9 years. When the crayfish has reached sexual maturity the females lay between 500 to 1000 eggs in late autumn. The eggs are carried on the female's setae and abdomen until they hatch in summer. Murray crayfish feed predominantly on decaying aquatic plant matter but will also eat dead animals. A centimetre (US: centimeter) is a factor of the SI unit of length: there are one hundred centimeters in the base unit of measure, the metre. ... A claw is a curved pointed growth found at the end of a toe or finger, or in arthropods, of the tarsus. ... The term carapace refers to a dorsal section of an exoskeleton or shell, in a number of animal groups. ... A seta is a stiff hair, wierd, culy, things bristle, or bristle-like process or part of an organism. ... The abdomen is a part of the body. ...

The Murray crayfish lives in large and small streams in from close to sea level to over 700 m above sea level; historically its distribution extended throughout the Murray-Darling Basin however fishing pressure and environmental change has resulted in the species no longer being found downstream of Mildura. It prefers cool, fast-flowing water. Semi-arid grazing country near Burra Creek, South Australia The Murray-Darling Basin drains one-seventh of Australia and is by far the most significant agricultural area on that continent. ... Mildura is a city in Victoria, Australia. ...

The species is threated by overfishing and as a result there are many restrictions in place for recreational fishers, all of which vary from state to state. In New South Wales these include a minimum size, bag and possession limits, and a ban on taking females with eggs. Further there is a limited season in which the species can be taken (start of May to the end of August). Murray crayfish are listed as vulnerable in the Australian Capital Territory, as endangered in South Australia and as vulnerable by the IUCN. The Traffic Light colour convention, showing the concept of Harvest Control Rule (HCR), specifying when a rebuilding plan is mandatory in terms of precautionary and limit reference points for spawning biomass and fishing mortality rate. ... Emblems: Floral - Waratah (Telopea Speciosissima); Bird - Kookaburra (Dacelo Gigas); Animal - Platypus (Ornithorhynchus Anatinus); Fish - Blue Groper (Achoerodus Viridis) Motto: Orta Recens Quam Pura Nites (Newly Risen, How Brightly You Shine) Slogan or Nickname: First State, Premier State Other Australian states and territories Capital Sydney Government Governor Premier Const. ... Emblems: ? (please edit) Motto: For the Queen, the Law and the People Slogan or Nickname: (none) Other Australian states and territories Capital Canberra Government Administrator Chief Minister Const. ... Emblems: Hairy Nosed Wombat (faunal); Sturts Desert Pea (floral); Opal (gemstone); Leafy Seadragon (marine) Motto: United for the Common Wealth Slogan or Nickname: Festival State Other Australian states and territories Capital Adelaide Government Governor Premier Const. ... The World Conservation Union or International Union for Conservation of Nature and Natural Resources (IUCN) is an international organization dedicated to natural resource conservation. ...

References

• Environment ACT. ACTION PLAN No.14, Murray River crayfish
• New South Wales Department of Primary Industries Prime Fact 4 Fishing for Murray crayfish in NSW