ABSTRACT
Baccharis occurs from Canada to the extreme south of South America, whereas section Caulopterae is exclusively South-American. The aim of this work is to study and analyse the geographic distribution patterns of Baccharis sect. Caulopterae in Rio Grande do Sul, Brazil. Geographic distribution data matrixes were evaluated by UPGMA (Unweighted Pair Group Main Average), using Jaccard's coefficient of similarity, to obtain the dendrograms. The existence of two floristic units in this taxon, one occidental and the other oriental, became obvious. There are two main distribution patterns; the first one represented by species centered in the Brazilian highlands, while the second pattern comprises species with their distribution centered in the lowlands of Argentina.
Keywords:
Compositae; biogeography; carqueja; Baccharis articulata; Baccharis trimera