Anthurium angustifolium Theófilo & Sakur., a new species of Anthurium (Araceae) sect. Urospadix subsect. Obscureviridia from Espírito Santo (Eastern Brazil) is described and illustrated. Anthurium angustifolium is closely related to A. viridispathum and A. gladiifolium. It differs from A. viridispathum by its deflexed leaves, purplish peduncle and spadix, and reddish berries, and from A. gladiifolium by its narrowly elliptic blades, with obscure secondary veins, and by a smaller number of flowers on the principal and alternate spirals. A key for Eastern Brazilian species of subsect. Obscureviridia is given and a comparison of the characters that separate A. angustifolium from related taxa is provided.