Taxonomic revision and phylogeny of Orthophytum Beer (Bromeliaceae, Bromelioideae)

Author(s)

Rafael Batista Louzada

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2012-09-03

Examining board members

Maria das Graças Lapa Wanderley; Tarciso Sousa Filgueiras; Rafaela Campostrini Forzza; Leonardo de Melo Versieux; Tânia Wendt

• Advisor: Maria das Graças Lapa Wanderley

Abstract

The genus Orthophytum Beer (Bromeliaceae) comprises 46 species geographically distributed in eastern Brazil extending from the state of Ceará in the North, to Minas Gerais and Espírito Santo in the South. The growth form of these plants is typically lithophytic, only rarely terrestrial, and granitic or quartzitic rocky outcrops constitute their favorite substrates. This work focuses on reconstructing the phylogeny of Orthophytum to clarify its relationships with closely related bromeliads, and to perform a taxonomic revision of the genus. This dissertation is structured in four chapters. The first chapter shows a phylogenetic analysis based on a molecular data set of two plastid markers ((psbA-trnH and trnL-trnF) and one nuclear (phytochrome C) that includes 40 species of Orthophytum, eight of Cryptanthus and two of Lapanthus. The combined analyses were not conclusive to elucidate the monophyly of Orthophytum, however it was possible to test the infrageneric groups. The second chapter presents a restablishment of Sicoraea genus, based on the results of the molecular analyses and on a careful evaluation of the morphological traits characterizing this group. In the third chapter, morphological characters are used to assign the species O. vidaliorum to the newly described genus Lapanthus. Finally, in the fourth chapter shows a taxonomic revision of the 46 recognized species of Orthophytum is presented. The taxonomic treatment includes descriptions of the genus and species and an identification key combined with distribution maps, detailed drawings and photo plates (AU)