A critically endangered new species of killifish sampled from an ancient forest in Kenya in 2017 and 2018 has been described in the journal Zootaxa .
Nothobranchius sylvaticus , from the Latin meaning “pertaining to the forest”, is also the first known endemic killifish to persist in a forest.
Prof. Dirk Bellstedt, emeritus professor of biochemistry at Stellenbosch University (SU), was part of the team of international scientists who sampled the fish from ephemeral swamps in the Gongoni Forest in south-eastern coastal Kenya. These expeditions in 2017 and 2018 were part of an “ Off the beaten track” research project , supported by the Volkswagen Foundation in Germany.
According to Bellstedt, this finding indicates that the Gongoni Forest itself is more than 7.09 million years old. Comprising only about 8.2 square kilometers, this ancient forest is a typical example of the East African Mosaic – a combination of savannah interspersed with forest patches that stretches from as far south as Pondoland in South Africa to as far north as southern coastal Somalia.
Since 2015, the team has been combining next-generation DNA sequencing of fish groups, such as Africa’s famous cichlid fishes, with high precision rock dating of key landforms in eastern Africa. The aim is to reconstruct the tectonic development of central Africa over the past 20 million years. During the past five to 30 million years, this region has undergone major tectonic activities and break ups.
For the scientists, the discovery of N. sylvaticus was one more example of the congruence between evolutionary events in the genus Nothobranchius with paleo-drainage dynamics, which were driven by the tectonic events that formed the East-African River Valley System.
However, due to the new species’ severely restricted habitat in an ancient forest, it also faces a high conservation risk.
The type specimen was deposited at the National Museums of Kenya in Nairobi, and the comparative specimens at the Royal Museum for Central Africa in Tervuren, Belgium.
The article titled “ The description of a critically endangered new species of seasonal killifish, Nothobranchius sylvaticus (Cyprinodontiformes: Nothobranchiidae), a relict species from an East African forest refugium in south-eastern Kenya ” was published in Zootaxa with authors Prof. Dirk Bellstedt (SU), Béla Nagy (France), Dr P. de Wet van der Merwe (SU), Dr Fenton P.D. Cotterill (The Wilderness Project—Great Spine of Africa, Wild Bird Trust), Quentin Luke (East African Herbarium, National Museums of Kenya), and Dr Brian R. Watters (Canada).
Zootaxa
Observational study
Animals
The description of a critically endangered new species of seasonal killifish, Nothobranchius sylvaticus (Cyprinodontiformes: Nothobranchiidae), a relict species from an East African forest refugium in south-eastern Kenya
6-Mar-2025
Not applicable