The Parastacidae are the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does in ...

crayfish Crayfish are freshwater crustaceans belonging to the clade Astacidea, which also contains lobsters. In some locations, they are also known as crawfish, craydids, crawdaddies, crawdads, freshwater lobsters, mountain lobsters, rock lobsters, ...

found in the Southern Hemisphere. The family is a classic

Gondwana Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final st ...

-distributed taxon, with

extant Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extinct, ...

members in

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the souther ...

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

, Australia,

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 List of islands of New Zealand, smaller islands. It is the ...

, and

New Guinea New Guinea (; Hiri Motu: ''Niu Gini''; id, Papua, or , historically ) is the world's second-largest island with an area of . Located in Oceania in the southwestern Pacific Ocean, the island is separated from Australia by the wide Torr ...

, and extinct

taxa In biology, a taxon ( back-formation from '' taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular n ...

also in

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest co ...

Distribution

Three genera are found in

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the eas ...

, ''

Virilastacus ''Virilastacus'' is a genus of freshwater burrowing crayfish species endemic to Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closes ...

'', '' Samastacus'' and ''

Parastacus ''Parastacus'' is a genus of southern crawfish in the family Parastacidae. There are about 15 described species in ''Parastacus'', found in South America. In addition, there are some preserved specimens from Australia that are possibly members of ...

'', the last of which also occurs disjunctly in

southern Brazil The South Region of Brazil (; ) is one of the five regions of Brazil. It includes the states of Paraná, Rio Grande do Sul, and Santa Catarina, and covers , being the smallest region of the country, occupying only about 6.76% of the territory ...

and

Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...

. There are no crayfish native to continental Africa, but seven species on

, all of the genus '' Astacoides''.

Australasia Australasia is a region that comprises Australia, New Zealand and some neighbouring islands in the Pacific Ocean. The term is used in a number of different contexts, including geopolitically, physiogeographically, philologically, and ecolo ...

is particularly rich in crayfish. The small genus ''

Paranephrops ''Paranephrops'' is a genus of freshwater crayfish found only in New Zealand. They are known by the English common names freshwater crayfish and koura, the latter from their Māori name of ''kōura''. The two species are the northern koura, '' P ...

'' is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

. The genera ''

Astacopsis ''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 endemic to

Tasmania ) , nickname = , image_map = Tasmania in Australia.svg , map_caption = Location of Tasmania in AustraliaCoordinates: , subdivision_type = Country , subdi ...

, while a further two are found on either side of the

Bass Strait Bass Strait () is a strait separating the island state of Tasmania from the Australian mainland (more specifically the coast of Victoria, with the exception of the land border across Boundary Islet). The strait provides the most direct wat ...

– ''

Geocharax ''Geocharax'' is a genus of southern crayfish in the family Parastacidae. There are two described species in ''Geocharax'', both found in Australia. '' Geocharax falcata'' is endemic to the North Grampians in Victoria. This species can be found ...

'' and ''

Engaeus ''Engaeus'' is a genus of freshwater crayfish found in Australia, the burrowing crayfishes. Fifteen of the 35 species in the genus occur in Tasmania, where they are known as the Tasmanian land crayfishes. The behaviour of these crayfish is notab ...

''. The greatest diversity, however, is found on the Australian mainland. Three genera are endemic and have restricted distributions ('' Engaewa'', ''

Gramastacus ''Gramastacus'' is a genus of freshwater crayfish species from southeast Australia. It has two described species. Discovery Two species of ''Gramastacus'' were originally scientific description, described in 1972 by Edgar Riek from the Grampian ...

'' and ''

Tenuibranchiurus ''Tenuibranchiurus'' is a genus of diminutive freshwater crayfish that live in the Australian state of Queensland. Only one species has been described, the swamp crayfish, ''T. glypticus''. ''Tenuibranchiurus glypticus'' is reportedly the sma ...

''), while two are more widespread and contain more than one hundred species between them: ''

Euastacus ''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 f ...

'', around the Australian coast from

Melbourne Melbourne ( ; Boonwurrung/ Woiwurrung: ''Narrm'' or ''Naarm'') is the capital and most populous city of the Australian state of Victoria, and the second-most populous city in both Australia and Oceania. Its name generally refers to a me ...

Brisbane Brisbane ( ) is the capital and most populous city of the states and territories of Australia, Australian state of Queensland, and the list of cities in Australia by population, third-most populous city in Australia and Oceania, with a populati ...

, and ''

Cherax ''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 A ...

'' across Australia and

. The Tasmanian genus ''Parastacoides'' was determined to be a synonym of ''Geocharax'', and is no longer valid.

Fossil record

The oldest specimens from the family Parastacidae are the

Albian The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous Epoch/ Series. Its approximate time range is 113.0 ± 1.0 Ma to 100.5 ± ...

fossils of '' Palaeoechinastacus'' from

Victoria, Australia Victoria is a state in southeastern Australia. It is the second-smallest state with a land area of , the second most populated state (after New South Wales) with a population of over 6.5 million, and the most densely populated state in ...

. The only northern hemisphere representative is also a fossil, '' Aenigmastacus crandalli'' from

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tota ...

References

External links

* {{Taxonbar, from=Q1190541 Crayfish Extant Albian first appearances Taxa named by Thomas Henry Huxley Decapod families