Ruellia capixaba (Acanthaceae, Acanthoideae), a new scandent species from espírito santo state, with taxonomic updates for other Ruellia of the Atlantic Forest of Brazil

Abstract Ruellia is the second most species-rich genus in the family Acanthaceae, comprising approximately 375 species that are primarily distributed in tropical and subtropical regions. In Brazil, 104 species of the genus are recorded, occurring across all biomes. The Atlantic Forest , recognized as a biodiversity hotspot, harbors 24 species of Ruellia , despite ongoing threats such as deforestation. In this paper, we describe and illustrate the new species Ruellia capixaba , endemic to the Atlantic Forest in Espírito Santo State, Brazil. We also propose a new name, Ruellia fatimae , for a red-flowered, scandent species transferred from the genus Stephanophysum , lectotypify Ruellia furcata , another species endemic to this biome, and provide an identification key to the scandent species of Ruellia occurring in the Brazilian Atlantic Forest.