Sistemática e conservação de Oocephalus (Benth.) Harley & J.F.B.Pastore (Hyptidinae), Lamiaceae

Abstract

The genus Oocephalus belongs to the subtribe Hyptidinae, family Lamiaceae, and currently comprises 22 species, 21 of which are endemic to the Brazilian campo rupestre. The genus species can be recognized for having a shrub or subshrub habit, aromatic, thyroid, short or elongated inflorescence, composed of pedunculate or sessile cymes, forming a simple or a compound dichasial cymes (or reduced to a single flower), ovoid and commonly enveloped by an involucrum of bracteoles, calyx tubular or infundibuliform, lobes deltate, ensiform, lanceolate or subulate, sinus between them obdeltate, corolla with an elongated tube and short lobes, these never marked with dots or lines. In chapter one of this thesis a nuclear phylogeny of Oocephalus using the Next Generation Sequencing (NGS) methodology, with the Angiosperms353 kit is presented; chapter two is a taxonomic review of the genus, with morphological descriptions, taxonomic and ecological comments about the species; and chapter three, an analysis of the genus distribution patterns, identifying areas with high species richness and endemism, evaluating the conservation status of the species. Phylogenetic analyzes recovered the genus as monophyletic, with species grouped into four distinct clades. The taxonomic review recognizes 24 species of Oocephalus and classifies them into four sections, previously recognized as clades in phylogenetic analyses. The analyzes also showed that the Oocephalus species have four distinct patterns of distribution and present a high risk of extinction, with 22 of the 24 species being classified in some group of threatened species. The results of this thesis show that Oocephalus can be use as model to test hypotheses about diversification and evolution in rupestrian fields, as it is a genus almost entirely endemic to these areas and, also, an important tool to assist in the conservation policies of the campos rupestres.