Anaspidacea is an order

Order (biology)

In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 of crustacean

Crustacean

Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...

s, comprising eleven genera in four families. Species in the family Anaspididae

Anaspididae

Anaspididae is a family of freshwater crustacean that is endemic to Tasmania, Australia. The family contains 3 genera and 5 species. This group of crustaceans are considered living fossils. They are commonly and collectively known as the Tasmanian anaspid crustaceans. Anaspidids have stalked eyes,...

 vary from being strict stygobionts (only living underground) to species living in lakes, streams and moorland

Moorland

Moorland or moor is a type of habitat, in the temperate grasslands, savannas, and shrublands biome, found in upland areas, characterised by low-growing vegetation on acidic soils and heavy fog...

 pools, and are found only in Tasmania

Tasmania

Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...

. Koonungidae is found in Tasmania and the south-eastern part of the Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

n mainland, where they live in the burrow

Burrow

A burrow is a hole or tunnel dug into the ground by an animal to create a space suitable for habitation, temporary refuge, or as a byproduct of locomotion. Burrows provide a form of shelter against predation and exposure to the elements, so the burrowing way of life is quite popular among the...

s made by crayfish

Crayfish

Crayfish, crawfish, or crawdads – members of the superfamilies Astacoidea and Parastacoidea – are freshwater crustaceans resembling small lobsters, to which they are related...

 and in caves. The families Psammaspididae and Stygocarididae are both restricted to caves, but Stygocarididae has a much wider distribution than the other families, with Parastygocaris having species in New Zealand

New Zealand

New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

 and South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 as well as Australia; two other genera in the family are endemic to South America, and one, Stygocarella, is endemic to New Zealand .

Genera

• Anaspididae
  Anaspididae
  Anaspididae is a family of freshwater crustacean that is endemic to Tasmania, Australia. The family contains 3 genera and 5 species. This group of crustaceans are considered living fossils. They are commonly and collectively known as the Tasmanian anaspid crustaceans. Anaspidids have stalked eyes,...
  
   Thomson, 1893
  • Allanaspides Swain, Wilson, Hickman & Ong, 1970 — Tasmania
  • Anaspides Thomson, 1894 — Tasmania
  • Paranaspides Smith, 1908 — Tasmania
• Koonungidae Sayce, 1908
  • Koonunga Sayce, 1907 — south-eastern Australia and Tasmania
  • Micraspides Nicholls, 1931 — south-eastern Australia and Tasmania
• Psammaspididae Schminke, 1974
  • Eucrenonaspides
    Eucrenonaspides
    Eucrenonaspides oinotheke is a species of crustacean in the family Psammaspidae , endemic to Tasmania, the only species described in the genus Eucrenonaspides. It was described from a spring at 9 Payton Place, Devonport, Tasmania in 1980, making it "the first spring-dwelling syncarid recorded from...
    
    Knott & Lake, 1980 — Tasmania
  • Psammaspides Schminke, 1974 — south-eastern Australia
• Stygocarididae Noodt, 1963
  • Oncostygocaris Schminke, 1980 — southern South America
  • Parastygocaris Noodt, 1963 — southern South America
  • Stygocarella Schminke, 1980 — New Zealand
  • Stygocaris Noodt, 1963 — southern South America, south-eastern Australia and New Zealand