Systematic Botany (2013), 38(3): pp. 692–713 © Copyright 2013 by the American Society of Plant Taxonomists DOI 10.1600/036364413X670359 New Insights into the Evolution of Passiflora subgenus Decaloba (Passifloraceae): Phylogenetic Relationships and Morphological Synapomorphies Shawn E. Krosnick,1,6 Kristen E. Porter-Utley,2,6 John M. MacDougal,3 Peter M. Jørgensen,4 and Lucinda A. McDade5 1Southern Arkansas University, Department of Biology, 100 East University Street, Magnolia, Arkansas 71753 U. S. A. 2Keene State College, Department of Biology, 229 Main Street, Keene, New Hampshire 03435 U. S. A. 3Harris-Stowe State University, Department of Mathematics and Natural Sciences, 3026 Laclede, St. Louis, Missouri 63103 U. S. A. 4Missouri Botanical Garden, Post Office Box 299, St. Louis, Missouri 63166 U. S. A. 5Rancho Santa Ana Botanic Garden, 1500 North College Avenue, Claremont, California 71753 U. S. A. 6Both authors contributed equally to this work. Authors for correspondence (
[email protected] or
[email protected]). Communicating Editor: Lucia G. Lohmann Abstract—Phylogenetic relationships of Passiflora subgenus Decaloba were examined using 148 taxa and four molecular markers: nuclear nrITS, ncpGS, cp trnL-F, and ndhF. Relationships of subgenus Decaloba to the other four Passiflora subgenera (Astrophea, Deidamioides, Tetrapathea,andPassiflora) are investigated, as are relationships among the eight supersections within subgenus Decaloba. Results indicate that subgenus Deidamioides is not monophyletic. Subgenus Astrophea + subgenus Deidamioides (section Tryphostemmatoides) together form the most basally branching lineage in the genus, followed by a clade comprised of subgenus Passiflora + subgenus Deidamioides (sections Tetrastylis, Polyanthea, and Deidamioides). Passiflora obovata (subgenus Deidamioides section Mayapathanthus) is resolved as part of subgenus Decaloba.