Monocorophium is a genus of amphipod

Amphipoda

Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. The name amphipoda means "different-footed", and refers to the different forms of appendages, unlike isopods, where all the legs are alike. Of the 7,000 species, 5,500 are classified...

 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.

Species

The genus Monocorophium comprises the following species:

• Monocorophium acherusicum (Costa, 1853)
• Monocorophium californianum (Shoemaker, 1934)
• Monocorophium carlottensis Bousfield & Hoover, 1997
• Monocorophium cylindricum (Say, 1818)
• Monocorophium insidiosum (Crawford, 1937)
• Monocorophium josei Valério-Berardo & Thiago de Souza, 2009
• Monocorophium oaklandense (Shoemaker, 1949)
• Monocorophium sextonae (Crawford, 1937)
• Monocorophium steinegeri (Gurjanova, 1951)
• Monocorophium tuberculatum (Shoemaker, 1934)
• Monocorophium uenoi (Stephensen, 1932)

Monocorophium acherusicum

Monocorophium acherusicum is a small (5 mm) species. It is brown with a very short abdomen, and has three little spines on its enlarged second antennae. It has rows of hair on its anterior legs, which it uses to filter food from the water. It naturally occurs in Europe, but was introduced to harbours of Australia by travelling in the ballast water of ships.

Monocorophium insidiosum

Monocorophium insidiosum builds tubes of mud and detritus on weeds, usually in brackish shallow subtidal waters, such as brackish lagoons, ditches and rivers. C. insidiosum occurs on American and European coasts from southern Baltic to eastern Mediterranean of North and South, and around Japan, and may grow up to 5 mm long.

Monocorophium sextonae

Monocorophium sextonae is 5 mm long and builds tubes of mud on algae, from shallow water up to 50 m deep. It occurs naturally 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...

, but was introduced into Plymouth

Plymouth

Plymouth is a city and unitary authority area on the coast of Devon, England, about south-west of London. It is built between the mouths of the rivers Plym to the east and Tamar to the west, where they join Plymouth Sound...

, Devon

Devon

Devon is a large county in southwestern England. The county is sometimes referred to as Devonshire, although the term is rarely used inside the county itself as the county has never been officially "shired", it often indicates a traditional or historical context.The county shares borders with...

 in the 1930s. In the late 1970 it was introduced to Ireland

Ireland

Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

, possibly by natural means from Devon. It can also be found along the European coast from southern Norway to the Mediterranean.