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| Author(s): |
Carolina Delfini Feliciano
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia |
| Defense date: | 2016-11-21 |
| Examining board members: |
Vinicius Castro Souza;
André Olmos Simões;
Gerson Oliveira Romão;
Juliana de Paula Souza;
Julie Henriette Antoinette Dutilh
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| Advisor: | Vinicius Castro Souza; Fernando Omar Zuloaga |
| Abstract | |
Poaceae is a osmopolitan family comprising about 700 genera and 10,000 species. Of these, approximately 220 genera and at least 1,500 species are native from Brazil. Poaceae is among the five richest families in species of the Flowering Plants and represents in America one of the most important families from the economical point of view. Axonopus P. Beauv. (about 90 species) and Paspalum (about 350 species) are distributed in tropical, subtropical and warm temperate regions of the New World, Brazil being important components of savannas and grasslands. These genera are placed in Panicoideae, tribe Paspaleae, subtribe Paspalinae. The objective of this study was to increase the knowledge we now have about Axonopus and Paspalum, through the taxonomic studies (emphasizing Brazilian species) and phylogenetic studies for Axonopus, as well as a taxonomic revision of Paspalum species included in Pectinata clade. Phylogenetic study included 52 ingroup species, covering all sections and series of Axonopus. Phylogenetic inference was based on maximum parsimony, maximum likelihood, and Bayesian analyses of DNA sequences from nuclear and plastid regions (ETS, ITS, ndhF and trnL-F), accompanied by investigation of possible morphological synapomorphies. Results from the analyses showed Axonopus monophyletic only with Centrochloa and Ophiochloa included. Three character states were mapped as probable synapomorphies and other three as autapomorphies. Our findings also showed that previous infrageneric classifications of the Axonopus were not supported and the species were segregated in two major lineages with supra and infrageneric relationships still not resolved. Therefore, the phylogenetic inferences presented here illustrate the need to extend species sampling, studies that combine morphological, anatomical and DNA datasets, as well as to revise the traditionally accepted infrageneric classification, which is principally based on the continuous and homoplasious character states of inflorescences and spikelets. Three thousand and five hundred specimens of 103 Brazilian and foreign herbaria were analyzed for the taxonomic study. In Brazil, it was found 53 species of Axonopus, of which 19 are exclusively distributed. In this chapter 298 names were included, 65 lectotypifications were proposed, being one of second-step, and not confirmed the occurrence of Axonopus ramosus for the Brazilian flora, as suggested in previous studies. Finally, in the taxonomic revision of Paspalum species placed in Pectinata clade, about 150 specimens of 35 Brazilian and foreign herbaria were analyzed, 15 names were revised, five lectotypifications were proposed and one epitype for Paspalum aspidiotes associated (AU) | |
| FAPESP's process: | 12/03412-5 - Phylogeny of Axonopus p. Beauv., taxonomic studies of the species from Brazil and revision of the Pectinata clade (Paspalum L.): Poaceae, Panicoideae, Paspaleae |
| Grantee: | Carolina Delfini Feliciano |
| Support Opportunities: | Scholarships in Brazil - Doctorate |