Understanding

Abstract

The South American genus Praxelis Cass. (Asteraceae, Eupatorieae) includes 18 species and is the second-largest genus of subtribe Praxelinae. It is distributed from Colombia, Venezuela and the Guianas, to central Argentina, southern Brazil and north-western Uruguay. Over the past 40 years, one species, P. clematidea, has invaded several countries around the world. To understand Praxelis and its species, this study provides an updated taxonomy with the re-establishment of P. urticeafolim var. nanum as a synonym of P. ostenii, 16 lectotypifications, clarification of morphology and geographical distribution, brief descriptions, and the first key to all the species in the genus.