O gênero Bulbostylis kunth (Cyperaceae) no Estado do Pará, Amazônia, Brasil.

Abstract

Cyperaceae Juss. it is the third largest family in number of species among the monocots, with wide distribution and remarkable diversity in the tropics and subtropics, and great dominance in temperate zones. In Brazil, it is distributed in all phytogeographic domains, and has about 646 species. Taxonomic studies focused on Cyperaceae in the Amazon biome are still minimal, but they are advancing strongly in the state of Pará, especially with publications of new species described for the region. These growing studies have been fundamental in the detection of taxa that need to have their taxonomy studied in a focused and detailed way, as in the case of Bulbostylis Kunth. This expressive genus of Cyperaceae comprise 227 species, with pantropical distribution and occurs mainly in campinaranas, campos rupestres, cerrados s.s., restingas and savannas. It is basically characterized by the presence of trichomes on the leaf sheath apex, style bifid or trifid, nutlets trigonous or biconvex, with stylopodium persistent or deciduous. Bulbostylis aggregates species with great morphological plasticity, which are generally associated with taxonomic problems that often promote forced specific determinations. Given the facts, this dissertation produced an unprecedented taxonomic treatment focused on Bulbostylis species occurring in the state of Pará, Brazil. The botanical material used came from collection expeditions and herbarium collections with expressive specimens from Pará (HBRA, HSTM, IAN, INPA, MFS, MG and UB). The results of this master's thesis are presented in two chapters, in the first "The genus Bulbostylis Kunth (Cyperaceae) in Pará state, Amazon, Brazil", are provided the taxonomic data of 20 species of Bulbostylis registered for the state of Pará, through an identification key, descriptions, comments, geographic distribution and habitat, in addition illustrations for all species; the second chapter presents the article recently submitted to Phytotaxa “Bulbostylis litoreamazonicola, a new species of Cyperaceae from the Brazilian Amazon coast” a new species of Bulbostylis is presented, having been determined and described during the production of the first chapter.