Aciotis (Melastomataceae): Two new species from the northwestern lowlands of South America

Two new species are described in the neotropical genus Aciotis. Aciotis wurdackiana is an herbaceous species with narrow chartaceous leaves, a dense cymose inflorescence, and chartaceous ovary walls, and is distributed in the northern state of Pará in Brazil. Aciotis olivieriana is an herbaceous species characterized by cordate and papery leaves, a lax cymose inflorescence, and coriaceous ovary walls, and is distributed in the lowlands of northwestern South America.