Tasmanian Mudfish, Neochanna cleaveri (Scott 1934)

Other Names: Australian Mudfush, Cleaver's Mud-trout, Eel Mud-trout, Eel-gudgeon, Mud Galaxias, Mud Trout, Tasmanian Mudfish, Tasmanian Mudtrout, Tasmanian Mud-trout

Tasmanian Mudfish, Neochanna cleaveri, from Victoria. Source: Tarmo A. Raadik. License: All rights reserved


A small slender golden to greenish-brown, brown or blackish galaxiid becoming grey to greyish-green below, with irregular darker blotches, bars and spots, small pelvic fins, very small eyes and large tubular nostrils.

Tasmanian Mudfish are able to partially aestivation to survive some drying of wetland habitats. 

Cite this page as:
Gomon, M.F. & Bray, D.J. 2022, Neochanna cleaveri in Fishes of Australia, accessed 28 Nov 2022, https://fishesofaustralia.net.au/home/species/4311

Tasmanian Mudfish, Neochanna cleaveri (Scott 1934)

More Info


Known only from low-lying areas coastal along southern Victoria from Wilsons Promontory to the Wye River and Glen Aire in the Otway Ranges, and in South Australia from Bool Lagoon and coastal habitats between Beachport and Robe, and in northern, western and south-eastern Tasmania and at Flinders Island (Bass Strait).

Tasmanian Mudfish are nocturnal, and inhabit permanent and ephemeral stagnant freshwater swamps, wetlands and drains - preferring muddy or silty areas with thick instream and emergent vegetation. Individuals are nocturnally active, and shelter amongst weeds or partly bury themselves in the muddy bottom during the day.

The species can aestivate by burrowing into muddy substrates or sheltering in moist substrates under rocks or debris helping it to tolerate partial or full drying of habitat.


Dorsal fin 9-11; Anal fin 10-13; Caudal fin 16; Pectoral fin 12-14; Pelvic fin 7; Gill rakers 9-13; Vertebrae 56-60.

Body elongate, slender, tubular; dorsal and ventral profiles nearly parallel; greatest body depth 7.0-10.0 in SL; head short; snout bluntly rounded and broad; eye small, 12.5-18.8% of HL, dorsolateral; anterior nostril elongated and tubular, projecting forward over upper lip. Scales absent.

Fins thick and fleshy at bases; pectoral fins small, paddle-shaped; ventral fin reduced; flanges of caudal peduncle strongly developed, usually confluent with anal and dorsal fin bases; caudal fin rounded.

Juveniles: snout rounded, head not depressed, upper end of pectoral-fin base about level with upper 40% of orbit; caudal fin forked.

Juveniles are often clearly the shortest individuals amongst whitebait caught.


To 14 cm SL, commonly to 8 cm.


Adults are golden to greenish-brown, and heavily pigmented with numerous irregular blotches, bars and spots.

Juveniles - transparent, almost unpigmented, with melanophores on snout and head between eyes; faint melanophores along lateral line sometimes with distinct fine spotting above; other rows mid-ventrally on abdomen, on dorsal profile of trunk and caudal peduncle, and along dorsal-, anal- and caudal-fin bases; eye silvery.


Little is known of the biology of the Tasmanian Mudfish. The species is amphidromous, spawning late in winter, and the newly hatched larvae are washed downstream and spend their first 2-3 months at sea or in estuaries. The 'whitebait' juveniles migrate upstream from estuaries into freshwater habitats.


  • Listed as Threatened under the Victorian Flora and Fauna Guarantee Act (1988) and as Critically Endangered in Victoria under the Advisory List of Threatened Vertebrate Fauna (DSE 2013). 
  • Considered Critically Endangered in South Australia. 
  • Tasmanian Mudfish are threatened by habitat loss and degradation through the clearing of swamps and wetlands, drainage and development, stock accessing habitats, and competition from alien species. Climate change is expected to increasingly impact this species. 
  • Remarks

    When the holotype was donated to the Museum, scientists experimented aestivating ability of the fish. They partly buried it in damp earth for up to 45 minutes at a time and watched it revive when returned to water. One day, the fish began to shrivel up, presenting “much the appearance of a dried-up worm, the whole body being shrunken and wrinkled.” Assuming the hardy fish had finally died, the scientists placed it in formalin.  “Immediately on coming into contact with the liquid, it revived, and demonstrated its vitality by several vigorous plunges, only to be overcome, in a few moments, by the preservative.” Scott (1933).

    Similar Species

    Differs from other galaxiids in having large, long tubular nostrils, a small head, small eyes, large round pectoral fins, small pelvic fins, large flanges on the caudal peduncle, and a low, rounded to oval-shaped dorsal fin that is elongated posteriorly.


    The species is named cleaveri, in honour of the collector, Mr. F. Cleaver of West Ulverstone, Tasmania. In 1932, Mr Cleaver found the holotype inside one of the roots of a eucalyptus stump growing in a swampy area, that he had blown up using explosives.

    Species Citation

    Galaxias cleaveri Scott, 1934, Pap. Proc. R. Soc. Tasm. 1933: 44 pl. 6. Type locality: West Ulverstone, Tasmania.


    Gomon, M.F. & Bray, D.J. 2022


    Atlas of Living Australia

    Tasmanian Mudfish, Neochanna cleaveri (Scott 1934)


    Allen, G.R. 1989. Freshwater fishes of Australia. T.F.H. Publications, Inc., Neptune City, New Jersey.

    Allen, G.R., Midgley, S.H. & Allen, M. 2002. Field Guide to the Freshwater Fishes of Australia. Perth : Western Australian Museum 394 pp. (as Galaxias cleaveri)

    Andrews, A.P. 1991. Observations on the Tasmanian mudfish, Galaxias cleaveri (Pisces: Galaxiidae). Papers and Proceedings of the Royal Society of Tasmania 125: 55–59. https://doi.org/10.26749/rstpp.125.55 (as Galaxias cleaveri)

    Cadwallader, P.L. & Backhouse, G.N. 1983. A guide to the freshwater fish of Victoria. Ministry for Conservation, Victorian Government Printing Office. (as Galaxias cleaveri)

    Chilcott, S.J. & Humphries, P. 1996. Freshwater fish of northeast Tasmania with notes on the dwarf galaxias. Records of the Queen Victoria Museum 103: 145-149. (as Galaxias cleaveri)

    DELWP. 2021. Flora and Fauna Guarantee Act 1988 Threatened List - June 2021 Department of Environment Land Water and Planning, Victoria.

    Fulton, W. 1986. The Tasmanian mudfish Galaxias cleaveri Scott. Fishes of Sahul 4(1): 150-151. (as Galaxias cleaveri)

    Green, R.H. 1984. The Tasmanian mudfish on Flinders Island. The Tasmanian Naturalist No. 77: 7. (as Galaxias cleaveri)

    Hammer, M. & Tucker, M. 2011. Baseline study and community monitoring of Australian Mudfish in South East, South Australia. Report to Department for Water, South Australian Government. Aquasave Consultants, Adelaide. 35 pp.

    Hammer, M.P., Adams, M. & Foster, R. 2012. Update to the catalogue of South Australian freshwater fishes (Petromyzontida & Actinopterygii). Zootaxa 3593: 59–74

    Jackson, P.D. & Davies, J.N. 1982. Occurrence of the Australian Mudfish, Galaxias cleaveri Scott, on Wilsons Promontory - First Record from Mainland Australia. Proceedings of the Royal Society of Victoria 94(1): 77-86. (as Galaxias cleaveri) See ref online

    Jackson, P.D. & Davies, J.N. 1983. The freshwater and estuarine fishes of Wilsons Promontory. Fisheries and Wildlife Division. Department of Conservation Forests and Lands: Melbourne. (as Galaxias cleaveri)

    Koehn, J.D. & O’Connor, W.G. 1990. Distribution of freshwater fish in the Otway Region, South-Western Victoria. Proceedings of the Royal Society of Victoria 102 (1): 29-39. (as Galaxias cleaveri) See ref at BHL

    Koehn, J.D. & Raadik, T.A. 1991. The Australian Mudfish, Galaxias cleaveri Scott, 1934, in Victoria. Proceedings of the Royal Society of Victoria. 103 (2): 77-86. (as Galaxias cleaveri) See ref at BHL

    McDowall, R.M. (ed.) 1996. Freshwater Fishes of South-eastern Australia. Sydney : Reed Books 247 pp. (as Galaxias cleaveri)

    McDowall, R.M. 1997. Affinities, generic classification and biogeography of the Australian and New Zealand mudfishes (Salmoniformes: Galaxiidae). Records of the Australian Museum 49(2): 121-137. https://doi.org/10.3853/j.0067-1975.49.1997.1262

    McDowall, R.M. & Frankenberg, R.S. 1981. The galaxiid fishes of Australia. Records of the Australian Museum 33(10): 443-605 figs 1-47 https://doi.org/10.3853/j.0067-1975.33.1981.195

    Merrick, J.R. & Schmida, G.E. 1984. Australian freshwater fishes: biology and management. Griffin Press Ltd., South Australia. 409 pp. (as Galaxias cleaveri)

    Raadik, T.A. 2006. Chapter 13. Freshwater fishes. pp. 133-148 in Museum Victoria and CSIRO Publishing. Melbourne's Wildlife. A Field Guide to the Fauna of Greater Melbourne. Melbourne : CSIRO Publishing 348 pp.

    Raadik, T.A. 2008. Family Galaxiidae. pp. 217-222 in Gomon. M.F., Bray, D.J. & Kuiter, R.H (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp.

    Raadik, T.A. 2014. Fifteen from one: a revision of the Galaxias olidus Günther, 1866 complex (Teleostei, Galaxiidae) in south-eastern Australia recognises three previously described taxa and describes 12 new species. Zootaxa 3898(1): 1-198 https://doi.org/10.11646/zootaxa.3898.1.1

    Scott, E.O.G. 1934. Observations on Tasmanian fishes with descriptions of new species. Papers and Proceedings of the Royal Society of Tasmania 1933: 31–53 figs 1–2 pls 6–8 See ref online

    Scott, E.O.G. 1936. Observations on fishes of the family Galaxiidae: Part 1. Papers and Proceedings of the Royal Society of Tasmania 1935: 85-112 figs 1-4 (described as Saxilaga (Saxilaga) anguilliformis) See ref online

    Scott, E.O.G. 1942. Description of Tasmanian mud-trout Galaxias (Galaxias) upcheri sp. nov. with a note on the genus Brachygalaxias Eigenmann, 1924, and its occurrence in Australia. Records of the Queen Victoria Museum, Launceston 1(1): 51-57 fig. 10 (described as Galaxias (Galaxias) upcheri) See ref online

    Waters, J.M. & McDowall, R.M. 2004. Phylogenetics of the Australasian mudfishes: Evolution of an eel-like body plan. Molecular Phylogenetics and Evolution 37(2): 417-425. https://doi.org/10.1016/j.ympev.2005.07.003

    Waters, J.M. & White, R.W.G. 1997. Molecular phylogeny and biogeography of the Tasmanian and New Zealand mudfishes (Salmoniformes: Galaxiidae). Australian Journal of Zoology 45(1): 39-48 https://doi.org/10.1071/ZO96049

    Whiterod, N.S., Hammer, M.P., Barnes, T.C., Tucker, M., Adams, M. & Raadik, T.A. 2020. Clear as mud: the ecology and conservation of a secretive wetland fish (Neochanna cleaveri:Galaxiidae) in a heavily altered landscape. Wetlands Ecology and Management 28: 779–795. https://doi.org/10.1007/s11273-020-09748-7

    Whiterod, N., Hammer, M., Freeman, R., Raadik, T. & Coleman, R. 2019. Neochanna cleaveri. The IUCN Red List of Threatened Species 2019: e.T122904064A123382186. https://dx.doi.org/10.2305/IUCN.UK.2019-3.RLTS.T122904064A123382186.en. Accessed on 03 March 2022.

    Quick Facts

    CAAB Code:37102003

    Biology:Amphidromous, larvae carried to sea

    Conservation:IUCN Endangered

    Depth:0-3 m

    Habitat:Coastal wetlands, estuarine, marine

    Max Size:14 cm SL


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