LARVAL DESCRIPTIONS OF 3 GALAXIID FISHES ENDEMIC TO SOUTH-WESTERN AUSTRALIA - GALAXIAS-OCCIDENTALIS, GALAXIELLA-MUNDA AND GALAXIELLA-NIGROSTRIATA (SALMONIFORMES, GALAXIIDAE)

The larval development of Galaxias occidentalis, Galaxiella munda and Galaxiella nigrostriata is described and illustrated with material col lected from freshwater habitats in south-western Australia. Galaxias o ccidentalis larvae are very elongate (52-54 myomeres), lightly pigment ed and morphologically very similar to those of Galaxias vulgaris and Galaxias maculatus. Notochord flexion (9.3-13.1 mm), formation of all except the pelvic fins (6.1-21.9 mm) and transition (>26.6 mm) in larv al G. occidentalis occur at similar sizes to larvae of the strictly fr eshwater G. vulgaris but at smaller sizes than in larvae of diadromous populations of G. maculatus. Larvae of Galaxiella munda and G. nigros triata are elongate (38-43 myomeres) and heavily pigmented and can be separated primarily by the considerably heavier pigmentation in the la tter species. Notochord flexion (6.6-13.1 mm), formation of all except the pelvic fins (5.8-13.6 mm) and transition (>13.2 mm) in both speci es occur at smaller sizes than in Galaxias larvae. Galaxias larvae can be distinguished from those of many superficially similar clupeiform species by the combination of a dorsal fin directly above the anal fin , lack of a strongly striated hindgut, absence of a conspicuous gas bl adder above the fore- and hindgut junction, and myomeres without cross -hatched muscle fibres. Galaxiella larvae are very different from Gala xias larvae and are unlikely to be confused with the larvae of any oth er sympatric species.