A Second Tree Species of Ampelozizyphus (Rhamnaceae), from the Upper Cuyarí River Basin, Guianía (Colombia)

Abstract. Ampelozizyphus kuripacorum from the upper rio Cuyari, Guiania department, Colombia, is described, illustrated, and its relationship with related species discussed. This new species differs from A. guaquirensis (the only other tree species in the genus) by its larger petioles, elliptic leaves, the domatia located only in the base the midrib on the lower surface, the glands (nectaries) on the leaf blades different in form, place and size, and the shorter, few- to single-flowered inflorescence. Updated keys to identify the genera of Rhamnaceae of Colombia and the species of Ampelozizyphus are provided.