Ruellia scarlatina, a new name for the sixty-year-old but misunderstood Ruellia capitata Rizzini (Acanthaceae)

Abstract

The name Ruellia capitata (Acanthaceae) given by Rizzini to the Brazilian species of the genus Ruellia, is an illegitimate name, as it is a later homonym of R. capitata described by D. Don based on specimens from Nepal in Asia. Therefore a new name, Ruellia scarlatina is proposed here for R. capitata. The detail description along with illustration, distribution map, conservation status, and morphological relationships, are provided. A key for the species of Ruellia with red flowers occurring in Goiás State, as well as coloured photographs of some of them, are also provided.