Taxonomy, anatomy and palynology of Paepalanthus fonsecae (Eriocaulaceae), a new species from central Brazil

The new species, Paepalanthus fonsecae (Eriocaulaceae), is described and illustrated. It is placed in P. sect. Conodiscus due to its dimerous flowers, subcylindrical receptacles, and a gynoecium with the nectariferous branches of the style inserted below the level of the short stigmas on the fused portion of the style. The new species is compared with similar congeners, especially P. echinoides, from which it is mainly distinguished by having an elongated aerial stem covered by membranaceous and flat leaves, and the inflorescences consisting of usually fewer but longer scapes, each subtending a wider capitulum with elliptic involucral bracts. Paepalanthus fonsecae is known from two collections from central Brazil in the municipalities of Alto Paraíso de Goiás and Cavalcante and, according to IUCN criterion B, it should be treated as critically endangered (CR). Detailed comments on the species' distribution and morphology, along with new anatomical and palynological data, are provided.