''Galaxias brevissimus'', the short-tail galaxias, is a

galaxiid The Galaxiidae are a family of mostly small freshwater fish in the Southern Hemisphere. The majority live in Southern Australia or New Zealand, but some are found in South Africa, southern South America, Lord Howe Island, New Caledonia, and the ...

of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

Galaxias ''Galaxias'' is a genus of small freshwater fish in the family Galaxiidae, and are frequently referred to as the galaxiids. These highly adaptable fish are typically found at temperate latitudes across the Southern Hemisphere. Galaxiids are ...

'', a member of the

Mountain Galaxias ''Galaxias olidus'', the mountain galaxias, is a species of freshwater galaxiid fish widely found in southeastern Australia. Description As for other members of the species complex, although ''Galaxias olidus'' exhibits a greater range of charac ...

species complex In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

group of freshwater fish, found in Australia.

Description

''Galaxias brevissimus'' is a fish with a typical

Galaxiid The Galaxiidae are a family of mostly small freshwater fish in the Southern Hemisphere. The majority live in Southern Australia or New Zealand, but some are found in South Africa, southern South America, Lord Howe Island, New Caledonia, and the ...

body form, with a long and tubular body, but distinguishable from other members of the family by a short

caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

(tail) and

caudal peduncle Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as see ...

, hence the common name. Size is commonly to , maximum recorded is . The colouration is generally a mottled brown on the upper surface and sides above lateral line, with this pattern continuing over the head and snout. The colouration is lighter below the lateral line becoming light brown or cream on the belly.

Distribution

This species has only been recorded from a creek in the very upper reaches of the coastal

Tuross River The Tuross River, an open semi-mature wave dominated barrier estuary or perennial stream, is located in the South Coast region of New South Wales, Australia. Course and features Tuross River rises of the eastern slopes of the Kybeyan Range, p ...

catchment in south eastern

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

. The location is at an elevation of AMSL about downstream from the source which is itself AMSL. The downstream distribution is unknown, but may have been more widespread in the past before the advent of introduced trout, which appear to have reduced and broken up its range.

Habitat

A wholly freshwater fish without a salt water phase in its lifecycle, ''G. brevissimus'' has only been found in one clear, open and gently flowing, small creek that was about across and around deep. The maximum recorded pool depth was . The creek consisted mostly of small pools connected by very short and shallow riffles with a creek bed of clay covered by sand, plus areas of silt. Cover within the creek was provided by rock,

macrophytes Aquatic plants are plants that have adapted to living in aquatic environments ( saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that ...

and overhanging grass. Creek side vegetation had been cleared for grazing, being replaced by pasture and grass tussocks. The general area surrounding the creek where the fish were recorded was disturbed, as a result of clearing for grazing.

Lifecycle/Reproduction

Breeding biology is unknown, however all adults examined during mid March were at an early stage of gonad development. The smallest fish collected during this time, , indicates a possible breeding season of late winter or early spring. ''Galaxias brevvissimus'' is not believed to migrate to the sea or the estuary during its life cycle.

Utility to humans

Not an angling target due to small size and conservation status.

References

{{Taxonbar, from=Q85762523 Galaxias Fish described in 2014 Taxa named by Tarmo Ain Raadik Freshwater fish of Australia