Rare Specimens Yield DNA to Confirm Additional Members of Tribe Stifftieae (Stifftioideae, Asteraceae) on the Guiana Highlands Tepuis

Abstract

Eight of the ten genera of the Guiana Highlands shrubby Mutisieae were sequenced for the ITS and ETS of the nuclear ribosomal DNA. Results from phylogenetic analyses of the sequence data are congruent with earlier reports that support two independent introductions from different lineages of the basal Asteraceae resulting in the diversification of these taxa in the Guiana Highlands. The two clades segregated according to corolla symmetry. The five genera with bilabiate corollas, Achnopogon, Duidaea, Eurydochus, Gongylolepis and Neblinaea, were supported with members of subfamily Stifftioideae whereas those with actinomorphic corollas, Chimantaea, Stenopadus and Stomatochaeta, constitute a monophyletic group sister to Wunderlichia and strongly supported in the Wunderlichioideae. Resolution, but not statistical support, was found for relationships within the Guiana Highlands shrubby Mutisieae.