This lineage occurs in the Heuningnes River System and in the Ratel River System. The subpopulations are fragmented and are all likely to be experiencing continuous decline due to the presence of piscivores, mainly Micropterus spp. This lineage meets the qualifying thresholds for Endangered B1ab(iii,v)+2ab(iii,v), as it is experiencing a continuous decrease in quality of habitat as well as a reduction in the number of mature individuals due the impacts of invasive alien fish. It is known from an extent of occurrence (EOO) of 435 km2, and area of occupancy (AOO) of 36 km2 and comprises three locations (the Upper Kars River, the Nuwejaars subcatchment and the Ratels River System). None of the known subpopulations of this lineage occur within protected areas.
Distribution
This lineage occurs in the Elands, Klipperdrift, Grashoek and Upper Kars Rivers in the Heuningnes River System as well as the Ratel River System on the Agulhas Plain, Western Cape Province, South Africa (Chakona et al. 2013).
Population sizes are unknown and studies are required to generate this information.
Threats
Galaxias sp. nov. 'Heuningnes' is threatened by the presence of piscivorous invasive aliens species, mainly Bass species (Micropterus spp.). Bass species are present in all subpopulations excluding in the Upper Kars River. Here it is protected by a low-water bridge but the long-term effectiveness of this barrier in preventing range expansion of the invasive alien fishes is uncertain.
Conservation
There are currently no conservation plans in place to protect this lineage.
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