The Shasta crayfish (Pacifastacus fortis), also known as the placid crayfish, is an endangered crayfish species endemic to California. It is found only in isolated spots on the Pit and Fall Rivers. It has always had a very small native range, and that range has been significantly fragmented by such human activities as damming, mining, and agriculture. To make matters worse, the signal crayfish, a recently introduced species, has very successfully outcompeted the Shasta crayfish in much of its range. The Pit River Fish Hatchery was closed in order to protect this species. The animal requires a constant, steady, and untainted flow of fresh water to survive. Further steps in the recovery plan for the species are underway. Jump to: navigation, search Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms. ... Jump to: navigation, search Phyla Porifera (sponges) Ctenophora (comb jellies) Cnidaria Placozoa Subregnum Bilateria  Acoelomorpha  Orthonectida  Rhombozoa  Myxozoa  Superphylum Deuterostomia     Chordata (vertebrates, etc. ... Subphyla and Classes Subphylum Trilobitomorpha Trilobita - Trilobites (extinct) Subphylum Chelicerata Arachnida - Spiders, Scorpions, etc. ... Orders Subclass Eumalacostraca  Superorder Eucarida   Order Amphionidacea   Order Decapoda - crabs, shrimp   Order Euphausiacea - krill  â€ Superorder Pancarida   â€ Order Thermosbaenacea  Superorder Peracarida   Order Amphipoda - amphipods   Order Cumacea - cumaceans   Order Isopoda - pillbugs, sowbugs   Order Lophogastrida   Order Mictacea   Order Mysida   â€ Order Spelaeogriphacea   Order Tanaidacea  Superorder Syncarida   Order Anaspidacea   Order Bathynellacea   â€ Order Palaeocaridacea   Order Stygocaridacea... Suborders Dendrobranchiata Pleocyemata Caridea Stenopodidea Reptantia 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. ... The word crayfish or crawfish can mean:- Sea crayfish, also called spiny lobster. ... Genera Astacus Austropotamobius Pacifastacus The family Astacidae comprises the freshwater crayfish native to Europe and western North America. ... Binomial name Pacifastacus leniusculus (Dana, 1852) The signal crayfish, Pacifastacus leniusculus, is an American crayfish indigenous to the western US. Due to the crayfish plague that ravaged European crayfish stocks and has almost exterminated the noble crayfish Astacus astacus, Swedish biologists searched for a crayfish that could replace the native... In biology, binomial nomenclature is a standard convention used for naming species. ... Jump to: navigation, search 1914 is a common year starting on Thursday. ... An endangered species is a species whose population is so small that it is in danger of becoming extinct. ... Jump to: navigation, search Families Astacoidea   Astacidae   Cambaridae Parastacoidea   Parastacidae Crayfish, sometimes called crawfish, lobsters, crawdads, mudbugs, carmels, yabbies, or spoondogs, 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 one of various ways of being not native (e. ... Jump to: navigation, search State nickname: The Golden State Other U.S. States Capital Sacramento Largest city Los Angeles Governor Arnold Schwarzenegger (R) Senators Dianne Feinstein (D) Barbara Boxer (D) Official languages English Area 410,000 km² (3rd)  - Land 404,298 km²  - Water 20,047 km² (4. ... The Pit River is a tributary of the Sacramento River, approximately 110 mi (176 km) long, in northeastern California in the United States. ... Binomial name Pacifastacus leniusculus (Dana, 1852) The signal crayfish, Pacifastacus leniusculus, is an American crayfish indigenous to the western US. Due to the crayfish plague that ravaged European crayfish stocks and has almost exterminated the noble crayfish Astacus astacus, Swedish biologists searched for a crayfish that could replace the native... Sweet clover (Melilotus sp. ...

The Shasta crayfish is thick and stocky, with relatively heavy chelae. It is usually dark brown dorsally with bright orange areas on its underside, but there is also a brilliant blue color morph. It is about 3 inches long. It lives in cold, clear, rocky areas of the mountain rivers and feeds on the slime coating the rocks. Jump to: navigation, search Mid-19th century tool for converting between different standards of the inch An inch is an Imperial and U.S. customary unit of length. ...

External Links

The US Fish & Wildlife Recovery Plan for the Endangered Shasta Crayfish