Systematics of Paepalanthus Mart. (Eriocaulaceae)

• Autor(a) principal: Caroline Oliveira Andrino
• Data de Publicação: 2018
• Tipo de documento: Tese
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
• Texto Completo: https://doi.org/10.11606/T.41.2018.tde-22082018-093910

Phylogenetic systematics has revolutionized biological classifications, increasing our understanding of the evolution of the characteristics of living beings and generating more efficient reference systems. At the same time, the computerization and the online availability of biological collections has facilitated consultations of type materials and determination updates. However, the genus Paepalanthus, which represents an important radiation of monocotyledons in the Neotropics and in campos rupestres vegetation, is far from being well-understood taxonomically and evolutionarily. The large numbers of species placed in non-monophyletic groups, and our poor understanding of species boundaries hamper understanding of their diversity. The focus of the present study was to improve our knowledge of this group by carrying out the most comprehensive phylogenetic study possible. The first chapter presents an overview of our current taxonomic knowledge of the family and the genus, as well as a newly revised list of valid names in Paepalanthus, which were only previously estimated. The list contains the infrageneric categories to which the species are assigned, their distributions, and comments when necessary. In the second chapter, a taxonomic study of Paepalanthus ser. Paepalanthus (P. [unranked] Variabiles) is presented, with the recognition of 127 species and delimitation of two complexes based on the examination of 16,000 exsiccate from Brazilian and other herbaria. A list of valid names, synonyms, nomenclatural notes, distribution maps, photographs of species in the field, and a discussion about the patterns found in Paepalanthus ser. Variabiles were produced. The third and last chapter presents the reconstruction of the phylogenetic hypothesis for Paepalanthus. It is based on data of three molecular markers (one plastid and two nuclear) obtained from 174 species of Paepalanthus, 20 species of other genera that emerged within Paepalanthus in previous phylogenies, and 12 species from external groups. The topology resulting from all of the analyses demonstrated good resolution, with well-supported clades, allowing the proposal of a new classification with consistent morphological correspondence