Novitates Gabonenses 93: a fresh look at Podostemaceae in Gabon following recent inventories, with a new combination for Ledermanniella nicolasii Author Bidault, Ehoarn https://orcid.org/0000-0001-5029-8069 Missouri Botanical Garden, Africa & Madagascar Department, St. Louis, Missouri, USA & Institut de Systematique, Evolution, et Biodiversite (ISYEB), Unite Mixte de Recherche 7205, Centre National de la Recherche Scientifique / Museum National d'Histoire Naturelle / Ecole Pratique des Hautes Etudes, Universite Pierre et Marie Curie, Sorbonne Universites, Paris, France ehoarn.bidault@mobot.org Author Boupoya, Archange https://orcid.org/0000-0002-8926-8737 Institut de Recherche en Ecologie Tropicale (IRET), Libreville, Gabon & Herbier National du Gabon, Libreville, Gabon Author Ikabanga, Davy U. Laboratoire d'Ecophysiologie et de Biodiversite Vegetale, Departement de Biologie, Faculte des Sciences, Universite des Sciences et Techniques de Masuku (USTM), Franceville, Gabon Author Nguimbit, Igor Laboratoire d'Ecophysiologie et de Biodiversite Vegetale, Departement de Biologie, Faculte des Sciences, Universite des Sciences et Techniques de Masuku (USTM), Franceville, Gabon Author Texier, Nicolas https://orcid.org/0000-0002-4045-992X Missouri Botanical Garden, Africa & Madagascar Department, St. Louis, Missouri, USA & Evolutionary Biology and Ecology Unit, Faculte des Sciences, Universite Libre de Bruxelles, Brussels, Belgium Author Rutishauser, Rolf Herbarium et Bibliotheque de Botanique africaine, Universite Libre de Bruxelles, Brussels, Belgium Author Mesterhazy, Attila https://orcid.org/0000-0001-7952-5990 Department of Systematic and Evolutionary Botany, University of Zurich, Switzerland Author Stevart, Tariq https://orcid.org/0000-0002-6212-0361 Missouri Botanical Garden, Africa & Madagascar Department, St. Louis, Missouri, USA & Evolutionary Biology and Ecology Unit, Faculte des Sciences, Universite Libre de Bruxelles, Brussels, Belgium & Centre for Ecological Research, Wetland Ecology Research Group, Debrecen, Hungary text Plant Ecology and Evolution 2023 2023-03-01 156 1 59 84 http://dx.doi.org/10.5091/plecevo.96359 journal article http://dx.doi.org/10.5091/plecevo.96359 2032-3921-1-59 A3301095CCAD56078E5F4CA25FE7E738 Dicraeanthus Engl. (Engler 1905: 94) Distribution. Endemic to Cameroon. Dicraeanthus africanus Engl. is widely distributed in Cameroon, and D. zehnderi H.E.Hess is restricted to the Sanaga and Mbam watershed. Habitat and ecology. Rapids and falls in rivers ca 50 to 600 m wide, 5-1050 m in elevation. Notes. Dicraeanthus was mentioned as present in Gabon by Sosef et al. (2006) , based on one collection ( Reitsma 2431 ) gathered in 1986 at the Poubara waterfalls on the Ogooue river. The collection was determined by the collector and was not observed by Cusset. This collection was supposedly deposited at WAG but could not be retrieved there. Duplicates of Reitsma collections are also present in NY, but this number could not be retrieved there either. The presence of this genus in Gabon could not be confirmed, despite the fact that the Poubara site was visited again in 2019. This collection by Reitsma might have been misidentified as Dicraeanthus , especially since a species name was not assigned by the collector. Since a hydroelectric dam was built at Poubara between 2008 and 2013, it is also possible that the Dicraeanthus population sampled by Reitsma in 1986 has since disappeared due to disturbance to the local environment, though four other Podostemaceae species were collected there in 2019: Ledermanniella pusilla , L. aloides s.l., Inversodicraea annithomae , and Tristicha trifaria . The presence of the genus Dicraeanthus in Gabon remains uncertain, and we choose to not accept it as present until the collection Reitsma 2431 can be observed by a specialist, or the species is collected in the field.