Phylogenetic Study of Apocynaceae Juss. And Aspidosperma Mart. And Zucc

530 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1999.The systematic analysis of species boundaries and relationships within the genus Aspidosperma was accomplished with a combination of phenetic and cladistic methods. The phenetic part of the study used principal components analysis (PCA) of morphological variation to establish basic units which were interpreted as species. A preliminary monograph of that genus Aspidosperma provides descriptions, exsiccatae, and distribution information for the thirty-six species that were recognized. The cladistic part of the systematic analysis of this taxonomic group used morphological and molecular characters. The morphological data was similar to that used for PCA, and the molecular sequence data was from both the nuclear genome (ITS-1 and ITS-2) and the chloroplast genome (trnL intron and trnL-F spacer). Phylogenies derived independently for each molecular data set were compared to assess possible hybridization. Parsimony analysis of all the data combined did not support the subgeneric concept proposed by some authors. These results did however support the maintenance of sectional categories however, with slight modifications. Section Myristicifolia was established, and sections Aspidosperma, Excelsa (including Inundata ), Polyneura, and Ramiflora were modified. Section Coutinia, Nobilia, Pungentia, Rigida, and Schultesia sensu Marcondes-Ferreira and Kinoshita (1996) were not modified. The combined results of PCA and parsimony analysis provided a framework in which ecological characters could be presented and discussed.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD