Abstract
Valeriana sobraliana, a new species from the highland grasslands of the Atlantic Rainforest Domain, Southern Brazil, is described and illustrated. The new species shares morphological affinities with V. catharinensis, V. organensis and V. ulei, but differs mainly by the leaves strongly discolorous and long-petiolate, as well as by the lanceolate and larger bracteoles, by the larger staminate flowers and by the elliptic achenes. It also differs by the distribution restricted to the High Altitude Tropical Grasslands of the Serra do Mar mountain range, Paraná state and border with the Santa Catarina state, in a remarkable disjunction with the other related species. Additionally, we provide the preliminary conservation status assessments using IUCN Red List categories and criteria, as well as a checklist and a key to the species of Valeriana in the Paraná state.