Golden galaxias

Golden galaxias
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Osmeriformes
Family: Galaxiidae
Subfamily: Galaxiinae
Genus: Galaxias
Species: G. auratus
Binomial name
Galaxias auratus
Johnston, 1883

The golden galaxias (Galaxias auratus) is a galaxiid fish of the genus Galaxias. It is endemic to Tasmania, Australia.

Description

It is medium to large for a galaxiid, usually growing up to 140 mm, occasionally to 240 mm, in length. It has a thickset body with a long head and slender snout. The upper body and sides are golden-amber in colouring, with dark oval spots. The underparts are silvery-grey, the fins amber to light orange edged black.[1]

Distribution and habitat

The golden galaxias is found only in Lakes Sorell and Crescent and their associated streams in the Central Highlands region of Tasmania. Adult fish prefer shallow, lake-shore waters with rocky substrates that provide shelter as well as breeding and feeding habitat.[1]

Behaviour

Breeding

The fish spawn from late autumn to winter. The small (1.5 mm diameter) eggs are stuck to rocky surfaces and aquatic vegetation, scattered rather than clumped. Some 1000–15,000 eggs are produced, depending on the age and size of the female. Newly hatched larvae are 5–6 mm long and float in the water column; the juveniles live in open water until 4–5 months old (when they reach a length of 40 mm) before moving to inshore lake bottom habitat. Males mature during their first year (at over 50 mm), and females in their second year (at over 70 mm). Most fish live for three or four years, though some individuals may reach six years or more.[2]

Feeding

As with other galaxiids, the fish are opportunistic carnivores. Juveniles feed on plankton and small insect larvae in the water column. Adults feed on a variety of aquatic and terrestrial insects, molluscs and crustaceans.[2]

Status and conservation

The species has been listed as Endangered under the Environment Protection and Biodiversity Conservation Act 1999 because of its very restricted range, with an estimated area of occurrence of about 76 km2. It is listed as Rare under the Tasmanian Threatened Species Protection Act 1995. It is threatened by diminishing habitat availability and habitat degradation.[1]

References

  1. 1.0 1.1 1.2 1.3 "Galaxias auratus (Golden Galaxias)". Threatened species & ecological communities. Department of Sustainability, Environment, Water, Population and Communities, Australia. 2011-06-24. Retrieved 2013-08-04.
  2. 2.0 2.1 "Galaxias auratus – Golden Galaxias". Species Profile and Threats Database. Department of Sustainability, Environment, Water, Population and Communities, Australia. 2013-07-16. Retrieved 2013-08-04.