A recent comprehensive survey of the Verlorenvlei River System that was conducted in January 2015 demonstrated that Galaxias sp. nov. 'Verlorenvlei' has a narrow distribution range which is divided into two fragmented subpopulations, in the upper Kruismans River and in the lower Verlorenvlei River. The upper Kruismans subpopulation is the most viable of the two subpopulations as it was represented by a range of size classes from juveniles to adults. This section of the upper Kruismans was also not invaded by alien invasive species. The lower Verlorenvlei subpopulation was represented by subadults and this section of the river has been heavily invaded by non-native Banded Tilapia (Tilapia sparrmanii). There are no instream physical barriers to protect the upper Kruismans subpopulation from invasion by alien invasive species. Thus, the two known subpopulations constitute one location. Presence of alien invasive species and excessive water abstraction are the key threats to this lineage. There is also a potential threat of tungsten mining in the future. Galaxias sp. nov. 'Verlorenvlei' has an area of occupancy (AOO) of 20 km2 (calculated using a 2x2 km2 grid) and an extent of occurrence (EOO) of 226 km2. It meets the qualifying thresholds for Endangered B1ab(ii,iii,v)+2ab(ii,iii,v).
Distribution
This lineage is endemic to the Verlorenvlei River System where it was found at only two localities during a survey of this system in 2015 in the upper Kruismans and the lower Verlorenvlei rivers.
Galaxias sp. nov. 'Verlorenvlei' is represented by two subpopulations which are fragmented. The adults were found in the upper Kruismans subpopulation, while the lower Verlorenvlei subpopulation was represented by subadults. These subpopulations are likely to become connected during the rainy season when surface flow in the Verlorenvlei becomes established.
Threats
The presence of alien invasive species and excessive water abstraction are the key threats to this lineage. The lower Verlorenvlei subpopulation is heavily invaded by alien invasive Banded Tilapia (Tilapia sparrmanii). Excessive water abstraction represents another major threat that has affected the persistence of pools in this dry-land river system through the dry season. There are potential threats to the lower Verlorenvlei subpopulation that are posed by the proposed tungsten mine in one of the upper catchments of the Verlorenvlei River System.
Uses and trade
All indigenous fish species of the Western Cape Province are listed as Endangered Wild Animals under Schedule 1 of the Provincial Nature Conservation Ordinance for the Western Cape, thereby preventing the collection and trade of the species without a permit. Translocations of indigenous freshwater fish species are controlled by Cape Nature’s Indigenous Fish Utilisation policy (Jordaan et al. 2016).
Conservation
There are currently no conservation plans in place to protect this lineage.
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