Abstract
Ruellia anamariae, a new species of Acanthaceae is herein described and illustrated from the municipalities of Parauapebas and São Geraldo do Araguaia, Pará State, Brazil. The new species is recognized by its habit, a shrub up to 5 meters high, by its terminal thyrsus inflorescence, by its greenish-yellow corolla with the expanded portion of the tube suburceolate, strongly revolute lobes and shortly exserted stamens. It is also morphologically similar to Ruellia exserta, but differs by its habit, a shrub (not liana), inflorescence, thyrsus with opposite dichasia (not secundiflorous thyrsus) and short exserted stamens (not long exserted), and to Ruellia beckii differing by its habit, a shrub (not liana) end calyx lobes oblong-lanceolate with acute apex (not oblanceolate to obovate with retuse to obtuse apex). We provide a detailed description, illustrations, comments, data on distribution and habitat and conservation status of the species.