Abstract
Castelnavia noveloi C. T. Philbrick & C. P. Bove is distinguished from other species of Castelnavia Tulasne & Weddell (Podostemaceae) based on the production of stems arising perpendicular from the leaf petiole (petiolar stems) and the flattened rachis of the pinnate leaves. The new species is only known from rio Taquarussu, east of the town of Taquarussu, Tocantins, Brazil.