A revision of the Peruvian species of Nasa ser. Alatae (Loasaceae)

The Nasa series Alatae is revised for Peru. Species limits in this group are reinvestigated on the basis of modem collections, all types and extensive field studies. A total of 12 species are recognized, seven of them - N. dillonii, N. driesslei. N. nubicolorum, N. pascoensis, N. sagasteguii, N. anderssonii and N. urentivelutina - are described as new to science. All new, and two of the previously recognized species are illustrated by line drawings. The species of this group are from Andean habitats, mostly cloud forests, and nearly all of them are narrow endemics.