Materials to the Taxonomic Revision of the Genus Epistephium (Orchidaceae, Vanilloideae) in Colombia

A synoptic revision of the genus Epistephium in Colombia based on morphological evidence is presented for the first time. A total of 19 species gathered in 3 morphological groups are currently recognized in the country, including two new records: E. ellipticum and E. sclerophyllum. Morphological characteristics of all the species are presented and illustrated by line drawings of their perianth segments, except E. lamprophyllum. An original key to the identification of Epistephium species reported in Colombia is provided along with information on their ecology, habitat, and geographical range. Epistephium amplexicaule is lectotypified based on Article 9.3 of the International Code of Nomenclature for algae, fungi, and plants as this name was published without a holotype.