Description and redescription ofGalaxiasspecies (Teleostei: Galaxiidae) from Otago and Southland

Abstract

There are two distinct genotypes and morphotypes of fish belonging to Galaxias vulgaris Stokell (sensu lato) in narrow sympatry in Healy Stream, a tributary of the Kye Burn in the Taieri River system, northeastern Otago. Therefore the present taxonomy of the species misrepresents the diversity of these fish. Analysis of allozymes using gel electrophoresis indicates at least four groups of populations. The two sympatric forms are clearly distinct species; the taxonomic status of the other geno‐ and morphotypes is more equivocal, but three species are recognised and described or redescribed here, on the basis of morphological and genetic evidence: Galaxias vulgaris Stokell (type locality: Rubicon River, Waimakariri River system, North Canterbury), present in and north of the Waitaki River; G. anomalus Stokell (type locality: a drain tributary of the Manuherikia River, between Ophir and Omakau, Clutha River), present in the Clutha and Taieri Rivers in Otago. in the rivers of Southland as far west as the Waiau River; G. depressiceps n.sp. (type locality: Healy Creek, tributary of the Kye Burn, Taieri River system) also present in the Clutha and Taieri Rivers, the Kakanui River in north Otago, and all the rivers of Southland also as far west as the Waiau River. Other populations in Otago are also variously distinct genetically or morphologically from the above three species. Decisions on their taxonomic status await further study.