Clarence Galaxias, Galaxias johnstoni Scott 1936

Known only from the Clarence Lagoon and its tributaries, Tasmania (42°05’S); temperate; generally benthic, inhabiting the margins of streams, swamps and shallow lakes around the shelter of rocks and boulders.

D 10-12; A 11-13; P 12-13; vertebrae 53-54

Body elongate, tubular; head blunt; mouth relatively large, reaching well below eye; jaws equal; depth at vent 7.6-9.1 in SL short, stout rakers on the first gill arch; lateral canines weak or absent; two pyloric caeca of moderate length.

Scales absent.

Caudal fin slightly emarginate or truncate; anal fin origin below middle to rear part of dorsal fin.

Maximum size is 14 cm TL, commonly to 7.5 cm.

Dark greyish-brown dorsally with irregular dark brown bars and blotches extending down sides, yellowish-cream ventrally.

Adults feed primarily on benthic crustaceans and insects; juveniles feed mainly on planktonic crustaceans and terrestrial insects.

Spawning occurs in Spring during which females produce approximately 300-200 eggs which are laid in masses beneath rocks. Entire life-cycle occurs in fresh water.

Eggs are 1.2-1.6mm diameter and adhesive.

Larvae hatch after 4-8 weeks at around 8mm TL living in open water until they reach 30mm TL and recruit to the adult benthic habitat.

Galaxias (Galaxias) johnstoni Scott E.O.G. (1936) Observations on fishes of the family Galaxiidae. Pap. Proc. R. Soc. Tasm. 1935: 85-112. Brown’s Marsh Rivulet, Clarence River, Tasmania.

Gomon 2010