The Tasmanian mudfish, ''Neochanna cleaveri'', is a small

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

amphidromous Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousan ...

fish in the galaxiid family, of the order

Osmeriformes The Osmeriformes are 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 Protacanthopte ...

Distribution

''Neochanna cleaveri'' is found in coastal wetlands of south eastern Australia: around

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

, Flinders Island in

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 waterwa ...

and southern Victoria particularly

Wilsons Promontory Wilsons Promontory, is a peninsula that forms the southernmost part of the Australian mainland, located in the state of Victoria. South Point at is the southernmost tip of Wilsons Promontory and hence of mainland Australia. Located at nearb ...

.R.M. McDowell, 1986. ''Freshwater Fishes of South East Australia'' (Rev Ed) Reed Books Australia, Sydney, pages = 64–65 0-7301-0462-1 Isolated populations occur in the Otways, near

Geelong Geelong ( ) (Wathawurrung: ''Djilang''/''Djalang'') is a port city in the southeastern Australian state of Victoria, located at the eastern end of Corio Bay (the smaller western portion of Port Phillip Bay) and the left bank of Barwon River, ...

and

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 met ...

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 elongated, tubular body, and moderately sized mouth, it may be distinguished from other galaxiid species by the small eye and the blunt, rounded head shape with protruding tubular nostrils over the upper lip. Pectoral fins are rounded. The pelvic fins are small and set at about the midpoint 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 fins are 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, they are greyish on their ventral surfaces, and marked with irregular darker mottled bands and blotches over the back, sides, and fin bases. Its length is up to 140 mm; commonly it grows to 80 mm.

Habitat

This species is 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 before 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. It adapts well to captivity and is easy to keep, but is secretive and nocturnal, limiting its appeal.

Conservation status

Tasmanian mudfish are 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.

Lifecycle

Spawning in late winter, the hatched larvae are washed out to sea, spending about 2 to 3 months at sea or in estuaries before returning to fresh water 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. Nocturnal in habit and secretive in nature, the fish usually rest during daylight in heavy vegetation or half buried in the muddy substrate. ''N. cleaveri'' can

aestivate Aestivation ( la, aestas (summer); also spelled estivation in American English) is a state of animal dormancy, similar to hibernation, although taking place in the summer rather than the winter. Aestivation is characterized by inactivity and a ...

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 include Australian mudfish, mud trout, and mud galaxias. Other scientific names include: ''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.

References

{{Taxonbar, from=Q44509 Tasmanian mudfish Freshwater fish of Tasmania Tasmanian mudfish