A New Species of Monrosia (Polygalaceae) from Argentina, and Revision of this Genus Endemic to the Southern Andes

<p>The recently resurrected monotypic genus <i>Monrosia</i> (Polygalaceae) is endemic to the Argentinian provinces of Catamarca to San Juan in the southern Andes. We here describe and illustrate <b><i>Monrosia sanjuanensis</i></b>, a new species endemic to the Province of San Juan and the second species of the genus, and revise the genus. <i>Monrosia</i> and its two species are described and analysed in a phylogenetic context, using nuclear and chloroplast DNA sequences. A distribution map, illustration, photos of the morphological structures of the two species, and taxonomic key are provided. We designate a lectotype for the name <i>M. pterolopha</i>.</p>