Phylogenetic of Pilocarpinae (Rutaceae)

Author(s)

Pedro Dias de Oliveira

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2008-07-10

Examining board members

Jose Rubens Pirani; Julio Antonio Lombardi; Antonio Carlos Marques; Alessandro Rapini; Vinicius Castro Souza

• Advisor: Jose Rubens Pirani

Abstract

This dissertation is composed of three major parts: I Basic Phylogenetics, II Phylogeny of Pilocarpinae, and III Taxonomic Novelties in Esenbecki- inae. Part I Basic Phylogenetics - provides a mini-review of some basic methods currently used in phylogenetics, covering theroretical and operational issues, and some of their implications as well. In the Chapter 1 I discuss two major concepts in phylogenetics, namely groups and characters, demonstrate how to build an evolutionary model and emphasize the importance of models in phylogenetics. As an outcome, the meanings of character evolution and groups are reviewed and improved under a probabilistic view. Chapter 2 presents an introduction to the very basic methods of tree construction and optimization using maximum likelihood and bayesian methods. Part II Phylogenetics of Pilocarpinae - presents a phylogeny of Pilocarpinae based on molecular data (internal trancribed spacers ITS1, ITS2, gene 5.8 S - from the nuclear DNA , and spacer trnG-S - from the plastidial DNA), and a phylogeny of Pilocarpus based on morphological and molecular (same DNA regions used before) evidence. Chapter 3 presents a generic-level phylogeny of the Pilocarpinae and allied genera (Balfourodendron and Helietta), which supports the monophyly of the traditionally recognized genera (Metrodorea and Pilocarpus , Raulinoa - monospecific), except Esenbeckia (which is included in a polytomy), whe- reas the subtribe itself is not monophyletic; it is also shown that Balfourodendron and Helietta (both from subtribe Pteleinae) are more closely related to some genera of Pilocarpinae than to the type genus of their own subtribe (Pteleinae), and emerge (together with Esenbeckia , Metrodorea , and Raulinoa ) nested within a clade that has multi-axis inflorescences, for which I created a new subtribe, leaving the Pilocarpinae monogeneric; moreover, this Chapter presents a new2 protocol to be used in MCMC diagnosis in phylogenetic studies. In the Chapter 4 , in turn, the phylo- geny of Pilocarpus is investigated based on morphological and molecular data; that phylogeny, combined to computer simulations, is then used to propose evolutionary hypotheses of leaf blade and corolla aestivation patterns, and show how appropriate the use of character states as synapomorphy/homoplasy can be using the MCMC method; additionally the MCMC and parsimony character mapping procedures are compared, and it is shown that synapomorphy/homoplasy is just a matter of probability. Part III Taxonomic Novelties in Esenbeckiinae is clearly a direct result of my field expeditions to the Amazon, and herbarium work. In the Chapter 5 I present a re-description and epitypification of E. cowanii Kaastra, previously known only from the type locality (and by the type specimens) and whose floral morphology was unknown, which I collected in Acre, Mato Grosso, Pará, and Rondônia States during my collecting trips in the Amazon; further, given the poor type material, I propose an epitype for the species. In the Chapter 6 I describe a new species of Esenbeckia (still without latin diagnose), which I collected in Acre and Rondonia states, whose diagnostic feature is the presence of persistent bracts. (AU)