Comparative floral morphoanatomy and pollen morphology reveal a new species of the <i>Dyckia selloa</i> complex (Bromeliaceae: Pitcairnioideae) in Rio Grande do Sul, Brazil

Abstract The taxonomic circumscription of many bromeliad species is doubtful, and this is the case for Dyckia alba. We explore unusual characters from several data sources, such as macromorphological, floral micromorphological, floral anatomy, and palynological, to more accurately circumscribe D. alba. In light of these data, we concluded that the originally proposed circumscription for D. alba covers two independent lineages that should be treated as two species. As a result, we propose a less comprehensive circumscription for D. alba and the segregation of a new species, described here as Dyckia witeckii. Morphological descriptions of the vegetative and reproductive organs are presented for both species, as well as little-explored morphological features in Dyckia, such as the micromorphology of perianth trichomes and pollen, along with the floral anatomy. We also provide, for both species, data on geographic distribution and habitat. Comparative morphoanatomy proved to be an important tool in this study and has great potential for application in taxonomic studies of Bromeliaceae.