The Tasmanian mudfish, Neochanna cleaveri, is a small 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 amphidromous fish in the galaxiid

Galaxiid

The Galaxiidae, also known by the anglicised name as galaxiids, are a family of mostly small freshwater fish in the southern hemisphere. The majority of species live in Australia or New Zealand, some are also found in South Africa, South America, Lord Howe Island, New Caledonia and the Falkland...

 family, of the order Osmeriformes

Osmeriformes

Osmeriformes is an order of ray-finned fish that includes the true or freshwater smelts and allies, such as the galaxiids and noodlefishes; they are also collectively called osmeriforms. They belong to the teleost superorder Protacanthopterygii, which also includes pike and salmon, among others...

.

Distribution

N. cleaveri is found in coastal wetlands of south eastern Australia: around 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...

, Flinders Island

Flinders Island

Flinders Island may refer to:In Australia:* Flinders Island , in the Furneaux Group, is the largest and best known* Flinders Island * Flinders Island , in the Investigator Group* Flinders Island...

 in Bass Strait

Bass Strait

Bass Strait is a sea strait separating Tasmania from the south of the Australian mainland, specifically the state of Victoria.-Extent:The International Hydrographic Organization defines the limits of the Bass Strait as follows:...

 and southern Victoria

Victoria (Australia)

Victoria is the second most populous state in Australia. Geographically the smallest mainland state, Victoria is bordered by New South Wales, South Australia, and Tasmania on Boundary Islet to the north, west and south respectively....

 particularly Wilsons Promontory

Wilsons Promontory

Wilsons Promontory is a peninsula that forms the southernmost part of the Australian mainland and is located at . South Point at is the southernmost tip of Wilsons Promontory and hence of mainland Australia...

. There are isolated populations in the Otways, near Geelong and Melbourne

Melbourne

Melbourne is the capital and most populous city in the state of Victoria, and the second most populous city in Australia. The Melbourne City Centre is the hub of the greater metropolitan area and the Census statistical division—of which "Melbourne" is the common name. As of June 2009, the greater...

 in Victoria as well as in far eastern South Australia near Naracoorte. The fish's range has been significantly reduced, especially in Victoria, due to destruction of suitable habitat through human activity such as swamp reclamation and drainage.

Description

Typically galaxiid in form, scaleless with an elongate, tubular body, and moderately sized mouth. May be distinguished from other galaxiid species by the small eye and the blunt, rounded head shape with protuding tubular nostrils over the upper lip. Pectoral fins are rounded. The pelvic fins are small and set at about the mid point of the fish's length and the dorsal and anal fins are set right back with the dorsal fin slightly ahead of the anal. Caudal fin rounded with well-developed flanges along the caudal peduncle reaching nearly to the posterior edges of the dorsal and anal fins. Greenish brown in colour, sometimes golden, greyish on the ventral survaces. Marked with irregular darker mottled bands and blotches over the back, sides and the fin bases. Its length is up to 140 mm, commonly to 80 mm.

Habitat

Found mostly in muddy swamps, marshes and drains with heavy vegetation. The fragmented populations in Victoria are likely to be remnants of a larger continuous population pre European settlement.

Importance to humans

Although individuals would be taken as part of the Tasmanian whitebait fishery, the numbers of this species involved is likely to be quite small. Adapts well to captivity and is easy to keep, but is secretive and nocturnal. limiting its appeal.

Conservation status

Not listed nationally as threatened due to their relative abundance in Tasmania. The fish is however, listed in Victoria as critically endangered under the Victorian Flora and Fauna Guarantee Act.

Life-cycle

Spawning in late winter, the hatched larvae are washed out to sea spending approximately 2 to 3 moths at sea or in esturies before returning to freshwater as part of the whitebait migration. Tasmanian mudfish are smaller than other species comprising the whitebait fishery, generally only 30 to 40 mm at this age. The juvenile fish migrate upstream to their usual habitat as mentioned above. Nocturnal in habit and secretive in nature, the fish usually rest during daylight hours in heavy vegetation or half buried in the muddy substrate. N. cleaveri can aestivate if water in its location dries up in summer or in times of drought, burying horizontally in the mud or by seeking out moist areas of substrate under rocks and logs.

Naming

Other common names: Australian mudfish, mud trout, mud galaxias

Other scientific names: Galaxias cleaveri, Saxilaga cleaveri, Saxilaga anguilliforms and Galaxias upcheri

The genus Neochanna is derived from the Greek Neos meaning new and Channa an Asian genus of aestivating fishes. The species name is derived from the fish's original collector Mr F. Cleaver.