Systematics, Biogeography and Leaf Anatomy and Architecture of Bursera subgen. Bursera (Burseraceae) in the Greater Antilles and the Bahamas

<p>This dissertation presents a comprehensive study on the origin and evolutionary relationships of the species of <em>Bursera</em> in Cuba, Hispaniola, Jamaica and the Bahamas. The goals of the first chapter were to test monophyly of the group, revisit a recent transfer of two species of <em>Bursera</em> to <em>Commiphora</em>, and place recently discovered mainland species using the reconstructed phylogenies. Additionally, divergence estimations using fossils were used as independent tests of several hypotheses regarding the arrival of the modern biota to the Greater Antilles and Bahamas (GAB). I conclude that all endemic taxonomic entities of the genus in this region belong to <em>Bursera</em> subgen. <em>Bursera</em> but that two separate lineages colonized the GAB via dispersal. The genus diversified during the Middle Miocene to Pliocene, and the data corroborate several paleogeographic events during that interval. The second chapter presents informative characters from leaf anatomy and leaf architecture for the 14 endemic species of <em>Bursera</em> distributed in the GAB. There is evidence for some evolutionary tendencies in the group, among them a trend toward small, simple, amphistomatic and unifacial leaves, character states for which ecological correlates can now be studied. Morphological and anatomical evidence corroborates phylogenetic results in suggesting that a population of <em>B. glauca</em> in Cuba is a new species. Finally, the third chapter constitutes the first taxonomic account and description of all known endemic species of <em>Bursera</em> in the region and reflects the results of the previous chapters. The primary results are as follows: (1) a new species from eastern Cuba, <em>B. yaterensis</em>, is described; (2) five species of <em>Commiphora</em> are returned to <em>Bursera</em>; (3) <em>B. nashii</em> is treated as conspecific with <em>B. glauca</em>; and (4) B. ovata is treated as conspecific with <em>B. trinitensis</em>. A dichotomous key is provided using mostly vegetative characters due to the frequent lack of adequate reproductive material and the relative uniformity of most floral and fruit characters. Each species description includes leaf architecture (morphology and venation pattern) and anatomy, introducing characters that could and should be used for describing and distinguishing other <em>Bursera</em> in Meso- and South America as well as for African <em>Commiphora</em>.</p>

Name thesis:degree_name

Botany, PhD

Level thesis:degree_level

Open Access Dissertation

Discipline thesis:degree_discipline

Botany

Year dc:date.available

2012

Author dc:creator

• Martínez-Habibe, María Cristina

Contributors dc:contributor

• Lucinda A. McDade
• J. Mark Porter
• Douglas C. Daly

• Biogeography
• Burseraceae
• Greater Antilles
• Leaf anatomy
• Leaf architecture
• Phylogenetics
• Physical and Environmental Geography
• Plant Biology

Repository record dc:identifier

https://scholarship.claremont.edu/cgu_etd/49

OAI identifier oai:identifier

oai:scholarship.claremont.edu:cgu_etd-1049