Various studies of mormyrids have indicated the differences in electric organ discharge (EOD) as a taxonomic character. This, together with morphological variation on PCA analyses (Maake et al. 2014), give sufficient evidence that the Kosi population of what is currently known as Marcusenius pongolensis belongs to a new undescribed taxon. Populations are known from the small streams that flow into the Kosi Bay estuary as well as from Kosi Lake. The estimated number of locations is five based on the current specimen records however more surveys are required to confirm the number of locations for this taxa. It has a extent of occurrence (EOO) ranging from 37 - 147 km2 as the inclusion of the Kosi Lake is still uncertain but highly likely and surveys are needed to confirm these records. It has an area of (AOO) of 20 km2-24 km2 and there is continuous decline in habitat quality as a result of increased human population near the rivers and Kosi Lake resulting in an increase in eutrophoication. This taxa needs to be monitored and more surveys are needed to inform future assessments. With the current knowledge the taxon qualifies as Endangered B1ab(iii)+2ab(iii).
Distribution
Only known from the tributaries of the Kosi Lake System in northern KwaZulu-Natal, South Africa. Local fisherman reported occurrence in the lake as well, this still needs to be confirmed.
There has been a significant increase in the human population in the area over the past 20 years. Pollution from high human settlement is impacting water quality (eutrophication) and has altered the habitat. An increase in the spread of invasive alien plants have been observed as a result of eutrophication, the presents of these invasive alien plants causes habitat degradation that may have secondary impacts on M. sp. nov. kosi. Further studies are required to understand the direct impacts of increasing human densities on the habitat of this taxon, however, their habitat is significantly degraded as a result of these threats.
Uses and trade
This genus is popular in the trade with individuals kept in aquariums and commonly referred to as "Little Dolphins". No direct evidence exist of this taxon being included in the aquarium trade but there is potential for it to be trade.
Conservation
Ezemvelo KwaZulu-Natal Wildlife have put conservation measures in-place such as the management of protected areas. However, threats still persist.
[@electronic{2426,
address = {www.iucnredlist.org},
author = {IUCN},
title = {The IUCN Red List of Threatened Species. Version 2017-3},
year = {2017}
}
,@article{107628552,
author = {Maake, P.A, Gon,O. and Swartz, E.R},
journal = {Zootaxa},
number = {3},
pages = {455--480},
title = {Description of three new species of <i>Marcusenius</i> Gill, 1862 (Teleostei: Mormyridae) from South Africa and Mozambique},
volume = {3780},
year = {2014}
}
,@article{107628552,
author = {Kramer, B, Maake, PA and Gon, O},
journal = {Zootaxa},
number = {3},
pages = {367--380},
title = {Electric organ discharges of South African Marcusenius species (Teleostei: Mormyridae) and their effectiveness as indicators of the local species diversity},
volume = {4200},
year = {2016}
}
,]
