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.
Cambarus is a large and diverse genus of crayfish from the United States and Canada. The adults range in size from about 5 cm (2.0 in) up to approximately 15 cm (5.9 in).
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.
Cambaroides is a genus of freshwater crayfish from eastern Asia. Together with Pontastacus, they are the only crayfish native to Asia. Cambaroides contains about six species:
Astacidae is a family of freshwater crayfish native to Europe, western Asia and western North America. The family is made up of four extant (living) genera: The genera Astacus, Pontastacus, and Austropotamobius are all found throughout Europe and parts of western Asia, while Pacifastacus is native to western United States and British Columbia, but has also been introduced elsewhere.
Corbicula is a genus of freshwater and brackish water clams, aquatic bivalve mollusks in the family Cyrenidae, the basket clams. The genus name is the Neo-Latin diminutive of Latin corbis, a basket, referring to the shape and ribs of the shell.
Parotocinclus is a genus of fish in the family Loricariidae native to South America. This genus is distributed through almost all hydrographic systems in South America from the Guyana Shield drainages and Amazon Shield tributaries to the coastal drainages of eastern and southeastern Brazil, including the rio São Francisco basin. Most species have the caudal peduncle oval in cross section. It has been found that Characidium species may interact with P. maculicauda. The small Characidium will follow grazing P. maculicauda, which release particulate matter dislodged from the catfish's foraging.
Cambarellus is a genus of small freshwater crayfish in the family Cambaridae. The 19 species are found in Mexico and the Gulf States of the United States. Among the Mexican species, C. areolatus, C. patzcuarensis, and C. prolixus are considered seriously threatened by the IUCN, and C. alvarezi is already extinct. C. chihuahuae was also believed to be extinct until rediscovered in 2012. C. alvarezi and four undescribed, extinct Cambarellus species were restricted to desert spring systems in southwestern Nuevo León; each one shared its habitat with a Cyprinodon pupfish.
Procambarus is a genus of crayfish in the family Cambaridae, all native to North and Central America. It includes a number of troglobitic species, and the marbled crayfish (marmorkrebs), which is parthenogenetic. Originally described as a subgenus for four species, it now contains around 161 species.
Walter Faxon was an American ornithologist and carcinologist. He was born at Jamaica Plain, Massachusetts, where he grew up. He received three degrees from Harvard University. One of his greater ornithological achievements was demonstration that Brewster's warbler is a hybrid.
Hyalella is a genus of amphipods found in the Americas. They are mainly found in freshwater habitats.
Cyclophorus is a genus of operculate land snails, terrestrial gastropod mollusks in the family Cyclophoridae.
Rhachistia is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Cerastidae.
The Aeglidae are a family of freshwater crustaceans currently restricted to South America. They are the only anomurans to be found in fresh water except for a single hermit crab species, Clibanarius fonticola, on Espiritu Santo, Vanuatu. They live between 20° S and 50° S, at altitudes between 320 and 3,500 m (1,050–11,480 ft).
Virilastacus is a genus of freshwater burrowing crayfish species endemic to Chile. It has four described species. The first species was described in 1914, but since 2005, three other species have been added to this genus.
Faxonius is a genus of freshwater crayfish in the family Cambaridae. There are more than 90 described species in Faxonius. It includes the rusty crayfish, an invasive species in North America, and three species, F. virilis, F. immunis, and F. limosus, that are invasive to Europe.
Moricandia is a genus of tropical air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Odontostomidae.
Stenophysa is a genus of gastropods belonging to the family Physidae.
Samastacus is a genus of southern crayfish in the family Parastacidae. It has a single species, Samastacus spinifrons.
