Three new species of Isoetes (Isoetaceae) are described from the Democratic Republic of the Congo, Rwanda and Burundi for inclusion in the family treatment for the Flore d'Afrique Centrale. Isoetes hallei sp. nov. is related to I. alstonii and I. schweinfurthii, I. rwandensis sp. nov. to I. abyssinica and I. welwitschii, and I. pichisermollii sp. nov. to I. abyssinica and I. schweinfurthii. The differences between these species are discussed and geographical distribution maps for the new species are presented. The conservation status of the new species is preliminarily assessed. The megaspores of the type specimens of I. abyssinica, I. alstonii, I. schweinfurthii and I. welwitschii were studied using Scanning Electron Microscopy to distinguish the new species from the more similar other ones.

Citation: Fischer E. & Lobin W. 2022: The genus Isoetes (Isoetaceae) in Central Africa (Democratic Republic of the Congo, Rwanda, Burundi) with the description of three new species. – Willdenowia 52: 315–334.

Version of record first published online on 1 December 2022 ahead of inclusion in December 2022 issue.