The newly described species of killifish, Nothobranchius sylvaticus, was discovered in Kenya’s Gongoni Forest during expeditions from 2017 to 2018. The species, critically endangered, diverged from its relatives 7.09 million years ago, indicating the forest’s ancient origins. The research emphasizes the ecological and evolutionary significance of this species while stressing the need for conservation due to its restricted habitat.
A newly identified species of killifish, known as Nothobranchius sylvaticus, has been documented in the journal Zootaxa. This critically endangered species, whose name translates to “pertaining to the forest,” is noteworthy for being the first endemic killifish to thrive in a forest environment.
Prof. Dirk Bellstedt, an emeritus professor of biochemistry at Stellenbosch University, was a member of the international research team that collected samples from ephemeral swamps within the Gongoni Forest in southeastern coastal Kenya during expeditions in 2017 and 2018. These efforts were part of the Volkswagen Foundation-supported project, “Off the beaten track.”
Scientific methods applied, including principal component analysis and DNA sequencing, confirmed the identification of N. sylvaticus as a distinct species. A dated phylogenetic analysis revealed that this lineage diverged from its sister species approximately 7.09 million years ago, suggesting that the Gongoni Forest itself is similarly ancient, dating back over 7 million years.
The Gongoni Forest, spanning merely 8.2 square kilometers, exemplifies the East African Mosaic—a blend of savannah and interspersed forest patches stretching from Pondoland in South Africa to southern coastal Somalia. Research since 2015 has integrated next-generation DNA sequencing of various fish groups with geological dating techniques to elucidate the region’s tectonic evolution over the last 20 million years. During this time, notable tectonic activities have occurred.
The discovery of Nothobranchius sylvaticus exemplifies the relationship between evolutionary changes in the genus Nothobranchius and paleo-drainage dynamics driven by tectonic formations in the East-African River Valley System. However, due to its limited habitat, this new species confronts substantial conservation challenges. The type specimen is preserved at the National Museums of Kenya in Nairobi, while comparative specimens have been sent to the Royal Museum for Central Africa in Tervuren, Belgium.
The research article “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 southeastern Kenya” features contributions from Prof. Dirk Bellstedt (SU), Béla Nagy (France), Dr. P. de Wet van der Merwe (SU), Dr. Fenton P.D. Cotterill (The Wilderness Project), Quentin Luke (East African Herbarium, National Museums of Kenya), and Dr. Brian R. Watters (Canada).
In summary, the identification of Nothobranchius sylvaticus signifies a notable scientific advancement in understanding biodiversity in forest ecosystems. The methodical analysis and historical context that accompany this discovery underscore the importance of conservation efforts for critically endangered species. This finding not only highlights the geological history of the region but also emphasizes the pressing need for habitat preservation against increasing environmental risks.
Original Source: www.sun.ac.za
