Revision of the South American species of the genus Trixis (Asteraceae, Mutisieae).

Abstract

The neotropical genus Trixis comprises 37 species of shrubs, subshrubs and herbs. This work is a taxonomic revision of the 21 South American species that includes a description of the genus, keys to the species, subespecies and related genera, and a list of excluded names. All taxa are described and illustrated and distribution maps are given. The systematic treatment is preceded by an analysis of morphological and anatomical characters: sterns, leaves, types of trichornes, corollas, phyllaries, achenes and disposition of the capitula. The new species T. peruviana is described, and two changes of status are proposed: T. antimenorrhoea (Schrank) Kuntze subsp. discolor (O.Oon) Katinas and T. verbascifolia (Gardner) Blake subsp. gigas (Wawra) Katinas. The new combination T. nobilis (Vell.) Katinas combo nov. for T. verbasciformis Less. is proposed.