Taxonomic position and identity of Stenocephalum monticola (Vernonieae, Asteraceae)

The genus Stenocephalum (Vernonieae, Asteraceae) includes six South American species that have cylindrical heads, 4–11 florets by capitula, cymose inflorescences and type ‘C’ pollen. Until now, Stenocephalum monticola has been considered as a synonym of S. apiculatum. However, the analysis of the type material and additional specimens indicate that it is a quite different species, which differs in leaf size, pubescence and capitula arrangement. Stenocephalum monticola has leaves of 9–20 mm long, leaf blades villous at the base and capitula agglomerate at the stems tips, while S. apiculatum presents leaves of 30–60 mm long, leaf blades basally glabrous and heads mostly solitary, arranged in a pseudo-spiciform inflorescence. Consequently, in this paper S. monticola is resurrected from the synonymy of S. apiculatum, re-described and illustrated.