Abstract
We describe and illustrate two new species of Calibrachoa, C. irgangiana and C. longistyla, from the Pampean region in southern South America. Calibrachoa irgangiana is characterized by a suite of characters: decumbent stems, viscid vestiture, the leaf midribs with a distinctive ligneous callus at the base, purple funnel-shaped corolla, and long stamens with connivent anthers opening at the mouth of the corolla tube. Calibrachoa longistyla is best recognized by its whitish corolla with the style apex and stigma exserted above the anthers of the longest stamens. Following the IUCN classification, both species are considered threatened.
