Synopsis of Pentacalia (Compositae: Senecioneae) in Brazil

Abstract The genus Pentacalia belongs to the tribe Senecioneae. It is represented by approximately 160 species predominantly distributed in the Andes. Species of Pentacalia are characterized by having a scandent habit, usually alternate leaves, axillary or terminal capitulescence, homogamous or heterogamous capitula, commonly yellow ray-florets, yellowish, creamy, or whitish disc-florets, sagittate to caudate anther-bases, and cypselae with five to ten ribs. The aim of the present study was to perform a taxonomic treatment of Pentacalia in Brazil, where it is represented by two species, P. desiderabilis and P. tropicalis, from the Atlantic Forest Domain. Detailed descriptions, taxonomic discussions, geographical distributions, an identification key, illustrations and a new record of P. tropicalis for the Northeast Region are presented. Moreover, three names (Senecio desiderabilis, S. ellipticus, and S. tropicalis) are lectotypified.