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.
Astacus is a genus of crayfish found in Europe, comprising three extant (living) species and three extinct fossil species.
Astacoidea is superfamily of freshwater crayfish that live in the Northern Hemisphere. The other superfamily of crayfish, Parastacoidea, lives in the Southern Hemisphere. Astacoidea consists of three families: Astacidae, Cambaridae, and Cambaroididae. Crayfish are closely related to lobsters, as shown in the simplified cladogram below:
Astacidea is an infraorder of decapod crustaceans including lobsters, crayfish, and their close relatives.
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.
The Cambaridae are the largest of the four families of freshwater crayfish, with over 400 species. Most of the species in the family are native the United States east of the Great Divide and Mexico, but fewer range north to Canada, and south to Guatemala and Honduras. Three live on the island of Cuba. The species in the genus Cambaroides are the only found outside North America, as they are restricted to eastern Asia.
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.
Metacarcinus starri is an extinct species of crab in the family Cancridae, subfamily Cancrinae. The species is known solely from the early Miocene, Clallam Formation and the underlying Pysht Formation deposits on the Olympic Peninsula of Washington state, United States.
Aciculopoda is an extinct prawn which existed in what is now Oklahoma approximately 360 million years ago. It was described in 2010 on the basis of a single fossil from Oklahoma. The single species, Aciculopoda mapesi, was named by Rodney Feldmann and Carrie Schweitzer in honour of Royal Mapes, a paleontologist who discovered the type specimen. It is only the third unambiguous fossil decapod from before the Mesozoic.
Penaeoidea is the larger of the two superfamilies of prawns. It comprises eight families, three of which are known only from fossils. The fossil record of the group stretches back to Aciculopoda, discovered in Famennian sediments in Oklahoma.
Platykotta akaina is a species of decapod crustacean from the Triassic of the United Arab Emirates. It is the oldest known fossil from the infraorder Anomura, and is most closely related to Eocarcinus praecursor.
Jurellana tithonia, the only species in the genus Jurellana, is a fossil crab. It was found in limestone rocks from the Ernstbrunn Formation in Austria, which have been dated to the Tithonian. It was originally thought to be the world's oldest porcelain crab, but was later determined to actually be a true crab.
Oregonia is a genus of crabs, comprising two extant species and one fossil species: It is classified in the family Oregoniidae under the spider crab superfamily Majoidea.
Tricarina is an extinct genus of crustaceans in order Isopoda, known from a single incomplete fossil specimen from the Cretaceous of western Iran. It has a flattened body with three longitudinal ridges, which give it its name.
Palaeoechinastacus australianus is a species of freshwater crayfish known from Early Cretaceous fossils from Victoria, Australia.
The McAbee Fossil Beds is a Heritage Site that protects an Eocene Epoch fossil locality east of Cache Creek, British Columbia, Canada, just north of and visible from Provincial Highway 97 / the Trans-Canada Highway. The McAbee Fossil Beds, comprising 548.23 hectares, were officially designated a Provincial Heritage Site under British Columbia's Heritage Conservation Act on July 19, 2012. The site is part of an old lake bed which was deposited about 52 million years ago and is internationally recognised for the diversity of plant, insect, and fish fossils found there. Similar fossil beds in Eocene lake sediments, also known for their well preserved plant, insect and fish fossils, are found at Driftwood Canyon Provincial Park near Smithers in northern British Columbia, on the Horsefly River near Quesnel in central British Columbia, and at Republic in Washington, United States. The Princeton Chert fossil beds in southern British Columbia are also Eocene, but primarily preserve an aquatic plant community. A 2016 review of the early Eocene fossil sites from the interior of British Columbia discusses the history of paleobotanical research at McAbee, the Princeton Chert, Driftwood Canyon, and related Eocene fossil sites such as at Republic.
Hoploparia is a genus of fossil lobster belonging to the family Nephropidae. The type species of this genus is Hoploparia longimana.
The paleofauna of the Eocene Okanagan Highlands consists of Early Eocene arthropods, vertebrates, plus rare nematodes and molluscs found in geological formations of the northwestern North American Eocene Okanagan Highlands. The highlands lake bed series' as a whole are considered one of the great Canadian Lagerstätten. The paleofauna represents that of a late Ypresian upland temperate ecosystem immediately after the Paleocene-Eocene thermal maximum, and before the increased cooling of the middle and late Eocene to Oligocene. The fossiliferous deposits of the region were noted as early as 1873, with small amounts of systematic work happening in the 1880-90s on British Columbian sites, and 1920-30s for Washington sites. Focus and more detailed descriptive work on the Okanagan Highlands site started in the last 1970's. Most of the highlands sites are preserved as compression-impression fossils in "shales", but also includes a rare permineralized biota and an amber biota.
Tillocheles is an extinct genus of decapod crustaceans that lived during the Cretaceous period. Two species are currently placed in the genus. Fossils of the earlier type species, T. shannonae, have been found in Queensland, while remains of the later species, T. kaoriae, are known from Hokkaido.
Protastacus is an extinct genus of decapod crustaceans that lived in what is now Germany during the early Cretaceous period. The type species is P. politus, and a second species, P. antiquus, is also assigned to the genus. Protastacus grew to around 10 cm (3.9 in) long and had a mostly crayfish-like appearance, with enlarged pincer-bearing appendages and a segmented abdomen. Though formerly assigned to the Astacidae or Nephropoidea, it is currently placed as the only genus in the family Protastacidae, which in turn is the only family in the superfamily Protastacoidea.
