Morphoanatomic and ontogenetic leaf characters of Metrodorea A.St.-Hil. and related species (Rutaceae) under a phylogenetic view

Author(s)

Rafael da Silva Cruz

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2013-10-03

Examining board members

Gladys Flávia de Albuquerque Melo de Pinna; Mariane Silveira de Sousa Baena; Benoit Francis Patrice Loeuille

• Advisor: Gladys Flávia de Albuquerque Melo de Pinna

Abstract

Metrodorea A. St.-Hil. is a Neotropical genus of Rutaceae, with species that have compound or 1-foliolated leaves and heterophylly, in addition to an intriguing bud-protecting structure on its basis. Available molecular phylogenies for the family indicate a need in reviewing its traditional classification, which must find support in appropriate morphological synapomorphies that support the new established groups. We conducted a study of leaf ontogeny and morphoanatomy of Metrodorea and related groups, under a phylogenetic framework, with data available in the literature and obtained from standard techniques in plant anatomy. In leaf primordia, the base formation is followed by acropetal differentiation of leaflet primordia, two paired proximal and one terminal on 3-foliated leaves, but only the terminal one on simple and 1-foliolated leaves. Leaflets rudiments were observed in heterophyllous species of Metrodorea. In species of this genus, at the base of the leaf, the protective structure emerges as paired appendages, revealing a stipular condition. The number of leaflets is dependent upon a greater or lesser determination of leaf primordium and its reduction may have been favored by the loss of leaflets as consequence of a restriction of the space required for development. Metrodorea synapomorphies found were: aborted leaflets, vascularized intrapeciolar stipules, glandular hairs in the proximal and adaxial region of the petiole, petiolulated leaflets, two seeds per locule in the fruit and valvar aestivation of the corolla. Their infrageneric relations are discussed according to the location of the crystals, adherence of the base of the leaves and the presence or absence of trichomes on the leaf blade. The close-relationship of the genus with Raulinoa is supported by a greater number of morphological synapomorphies than with other genera. The monophyly of Esenbeckia finds no support in our data and Helietta + Balfourodendron (formerly of another subfamily) are more related to Esenbeckia, Raulinoa and Metrodorea (former Pilocarpinae) than Pilocarpus, and such relationship is sustained by the presence of glandular hairs on the petiole, rhombohedral prismatic crystals, conate carpels and dorsal apophysis of the fruit (AU)

• FAPESP's process: 11/04258-7 - Morphoanatomic and ontogenetic foliar characters of Metrodorea A.St.-Hil. and related species (Rutaceae) under a phylogenetic perspective.
• Grantee: Rafael da Silva Cruz
• Support Opportunities: Scholarships in Brazil - Master