Article révisé par les pairs
Résumé : Three new Orchidaceae species from Rio Muni (Equatorial Guinea) and Gabon are described and illustrated: Polystachya bipoda Stévart, P. lejolyana Stévart and P. riomuniensis Stévart & Nguema. Three new combinations are proposed: Polystachya albescens Ridl. subsp. polyphylla (Summerh.) Stévart, P. odorata Lindl. subsp. gabonensis (Summerh.) Stévart and P. odorata Lindl. subsp. trilepidis (Summerh.) Stévart.