Bauhinia naniflora : a new species of section Amaria (Cercidoideae: Leguminosae) from Colombia

Bauhinia , the most species‐rich genus of Cercidoideae (Leguminosae), is pantropically distributed and includes four sections in the Americas. During an ongoing taxonomic revision of American Cercidoideae, a new species of Bauhinia sect. Amaria ser. Decandrae currently endemic to Colombia was identified and is here described as Bauhinia naniflora sp nov. The new species is morphologically similar to Bauhinia petiolata var. petiolata and Bauhinia brachycalyx by exhibiting entire leaves and relatively small flowers, but it is readily distinguished from them by a combination of leaf, floral, and fruit characters. Bauhinia naniflora is known from a few localities in the middle Magdalena River Valley and the western slopes of the eastern Cordillera of Colombia, where it inhabits moist and dry forests between 300 and 1600 m a.s.l. Based on its restricted distribution, small area of occupancy, and ongoing habitat degradation, the species is preliminarily assessed as ‘Endangered' (EN) under IUCN criteria. A detailed morphological description, illustration, photographic plate, distribution map, ecological notes, and comparisons with morphologically similar taxa are provided. In addition, an identification key to the Colombian species of Cercidoideae with entire leaves is provided.