A deeper look into the diversity of suckermouth catfishes (Mochockidae: Chiloglanis Peters 1868) of southern Africa, with the description of four new species

Suckermouth catfishes of the genus Chiloglanis Peters 1868 are small and predominantly rheophilic fishes endemic to Africa. This genus is quite diverse, with over 70 species distributed across most river systems on the continent, except for the Cape Fold ecoregion and most of northern Africa. The present study undertook detailed genetic and morphological examination of suckermouth catfishes collected from multiple localities across the Zambezi River system. Results from this study support preliminary field observations that had identified considerable morphological and colour pattern variation among specimens collected from this system, which were all previously lumped together into the 'basket' name, Chiloglanis neumanni. Herein, we describe four new species: Chiloglanis imberbis sp. nov., Chiloglanis shirensis sp. nov., Chiloglanis lapidis sp. nov. and Chiloglanis brevispina sp. nov. based on a combination of molecular differentiation and distinctive morphological traits. We discuss additional diversity within this group that will be addressed in a future follow-up study of this group. Accurate species identification within widely distributed model taxa is fundamental to reconstructing historical biogeographic processes. In the case of suckermouth catfishes, a genus with a pan-African distribution, resolving taxonomic diversity and clarifying distributional boundaries will provide future biogeographic studies with the important ingredients to unravel historic patterns of drainage evolution and connectivity patterns across the continent. Additionally, the urgent need for conservation of habitats such as montane streams that not only play a pivotal role in providing water resources but also harbour high levels of endemic biodiversity is highlighted.