Kosciuszko Galaxias

📖 Overview

Facultative air-breathing in the genus ; A freshwater fish that is unable to undertake diadromous migrations. Collected from cold and clear water in small flowing creeks (0.6-1.1 m average width, 0.1-0.2 m average depth, 0.5-0.6 m maximum depth) and from an on-stream lake (Blue Lake). All sites during winter are covered by snow and ice for an extended period of time. Substrate in the creeks consisted of bedrock, boulder, cobble, gravel and sand while the lake with cobble, pebble, gravel and silt.The fish is collected among rock, undercut banks and overhanging grasses in the creeks, mainly from pools. In Blue Lake, collected among small cobbles and from within 2 m of the shoreline (location and habitat in deeper water unknown). All sites without emergent or submerged aquatic vegetation or overhead shading. Collected at a density of 4.5 fish/m2 in Carruthers Creek, 2.5 fish/m2 along the edges of Blue Lake, and 1.5 fish/m2 in an inflowing tributary to Blue Lake. It is the only native fish species so far recorded from within its range, although Galaxias olidus is presumed to be present nearby. It is collected in Carruthers Creek with an unidentified native spiny crayfish Euastacus sp. (possibly E. rieki) .

🔬 Taxonomy

🐟 Physical Description

Dorsal soft rays (total): 9 - 11; Anal soft rays: 10 - 12; Vertebrae: 52 - 58. This species is distinguished from its congeners within the Galaxias olidus complex by the following characters: pelvic fin with 8 segmented rays; mean vertebral count very high 57, with broad range (52-59); distinct subterminal mouth; dorsal, anal and pelvic fin origins are set far back along trunk (70.4-75.1, 74.8-80.2 and 49.7-55.6 % SL respectively); distance between pectoral and pelvic fin bases is long (27.8-35.7 % SL); body depth shallow (8.4-12.4 % SL), much greater through pectoral fin base (11.8-16.4 % SL) than that through vent; caudal peduncle is very short and shallow (10.0-12.7 and 6.3-8.9 SL respectively); caudal fin much longer (120 %) than caudal peduncle; snout long (26.7-34.9 % HL); eye small (13.1-20.7 % HL); nostrils short and not visible from ventral view; anal fin base short (8.7-10.9 % SL); dorsal and anal fins short (12.6-15.9 and 13.1-15.9 % SL respectively); dorsal midline usually flattened anteriorly from above or slightly posterior to pectoral fin bases; posterior extent of mouth about 0.8 eye diameter below ventral margin of eye; usually 2, occasionally 1; pyloric caecae of moderate length (4.6 % SL); gill rakers are short to moderately long; anal fin origin usually under 0.85 distance posteriorly along dorsal fin base (greatest setback in all members of the species complex); no distinct black bars along lateral line though, very occasionally, dark patches on dorsal midline may have a very small, black bar in the centre; and, distinctive, mottled colour pattern .Cross section: oval.

🌀 Behaviour

Behavioural data for Kosciuszko Galaxias is currently being reviewed.

🦐 Diet

🥚 Reproduction

🌍 Habitat & Distribution

Freshwater; benthopelagic; non-migratory; depth range 0 - 1 m . Subtropical

🌿 Ecology

📐 Morphometrics

🌡️ Water Parameters & Tolerance

🛡️ Conservation Assessment

📊 Population Risk & Fisheries

🐠 Related Species

🔍 Similar Species

👥 Community & Contribute