Hidden species diversity in Marcusenius moorii (Teleostei: Mormyridae) from the Congo Basin

A new species of electric fish, Marcusenius verheyenorum, has been discovered within the Okapi Wildlife Reserve and Yangambi Biosphere Reserve in the Congo Basin. This finding reveals hidden biodiversity in what was previously thought to be a single species, Marcusenius moorii. The study used morphological and genetic analyses (mtDNA, cytb) to distinguish M. verheyenorum from its congeners, identifying unique traits such as eight circumpeduncular scales, a rounded head with a terminal mouth, and a deep body with 38–43 lateral line scales. Additionally, Marcusenius lambouri, previously considered a junior synonym of M. moorii, was revalidated based on distinct morphological differences. The research also highlights the sympatric occurrence of M. moorii and M. lambouri in the middle Congo Basin while noting the potential local extinction of M. verheyenorum due to anthropogenic pressures.

Mambo Baba, T., Kisekelwa, T., Danadu Mizani, C., Decru, E., & Vreven, E. (2020). Hidden species diversity in Marcusenius moorii (Teleostei: Mormyridae) from the Congo Basin. Journal of Fish Biology, 96(5), 1100–1122. Portico. https://doi.org/10.1111/jfb.14226