The Genus Columnea (Gesneriaceae) in Ecuador

A survey of the Ecuadorian species of Columnea with a key to the 57 accepted species is presented, and their distribution is discussed. Eighteen species are newly described: Columnea albiflora, C. capillosa, C. cinerea, C. densibracteata, C. fililoba, C. fimbricalyx, C. fuscihirta, C. gigantifolia, C. inconspicua, C. laevis, C. lavandulacea, C. leucerinea, C. longinervosa, C. minutiflora, C. ovatifolia, C. purpurimarginata, C. rubribracteata, and C. rubricalyx. The segregate genera Pentadenia, Dalbergaria, and Trichantha and the small genus Bucinellina are included in Columnea, requiring three new names (C. elongatifolia for Trichantha angustifolia, C. flexiflora for Trichantha dodsonii, and C. tenella for Trichantha gracilis), and ten new combinations. In addition, Alloplectus microsepalus is transferred to Columnea. Five species are lectotypified and seven species are neotypified. These were for the most part described by Mansfeld based on material at Berlin and later destroyed. Nineteen Columnea species are known only from Ecuador, 32 Ecuadorian species also occur in Colombia, 11 occur in Peru, five in all three countries, and four in Panama, as well. Columnea microsepala and C. matudae have remarkable disjunctions, the first between coastal Ecuador and coastal Venezuela and the latter between southern Ecuador and southern Mexico. In Ecuador, 42 and 22 species occur west and east of the Andes mountains, respectively, and seven species occur on both sides. Nineteen species are only known from a single Ecuadorian province, but only five of these are endemic to Ecuador. The largest diversity exists in the most humid part of Ecuador—the northwestern provinces of Carchi and Esmeraldas.