University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 5-2008 Systematics of Gratiola (Plantaginaceae) Larry D. Estes University of Tennessee - Knoxville Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Part of the Ecology and Evolutionary Biology Commons Recommended Citation Estes, Larry D., "Systematics of Gratiola (Plantaginaceae). " PhD diss., University of Tennessee, 2008. https://trace.tennessee.edu/utk_graddiss/381 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Larry D. Estes entitled "Systematics of Gratiola (Plantaginaceae)." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Ecology and Evolutionary Biology. Randall L. Small, Major Professor We have read this dissertation and recommend its acceptance: Edward E. Schilling, Karen W. Hughes, Sally P. Horn Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) To the Graduate Council: I am submitting herewith a dissertation written by Larry Dwayne Estes entitled “Systematics of Gratiola (Plantaginaceae).” I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the requirements for the degree of Doctor of Philosophy, with a major in Ecology and Evolution. Randall L. Small, Major Professor We have read this dissertation and recommend its acceptance: Edward E. Schilling Karen W. Hughes Sally P. Horn Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official student records.) Systematics of Gratiola (Plantaginaceae) A Dissertation Presented for the Doctor of Philosophy Degree The University of Tennessee, Knoxville Larry Dwayne Estes May 2008 ACKNOWLEDGMENTS I want to thank the former Department of Botany and the present Department of Ecology and Evolutionary Biology at the University of Tennessee for the general support provided to me during the past four and a half years. I owe a special thanks to my Ph.D. advisor, Dr. Randy Small, for his patience, guidance, and friendship. Sincere gratitude is also extended to the members of my Ph.D. committee including Dr. Sally Horn, Dr. Karen Hughes, and Dr. Ed Schilling, each of whom has contributed significantly to my overall education. It pleases me to also thank Dr. B.E. Wofford, whom I have admired and looked up to for many years now. His frequent fatherly advice and close friendship have served me well during my tenure at the University of Tennessee. Next, I would like to thank John Beck for his great friendship, assistance in the lab, and companionship in the field. I want to thank several of my colleagues for their friendship and/or assistance: Tatiana Arias, Dr. Hal DeSelm, Edgar Lickey, Wusheng Liu, Joey Shaw, Mary Stevenson, Mackenzie Taylor, Matt Valente, and Charles Winder. I’d like to especially thank Joey Shaw and Ed Lickey for constantly disagreeing with me on my taxonomic philosophy, without this experience, my time at UT would have been simply less than stimulating. The following sources provided financial support for this project: Ecology and Evolutionary Biology Summer Research Grant, the University of Tennessee; Sharp Fund, the University of Tennessee; Hesler Fund, the University of Tennessee; Dennis- Breedlove Fund for Field Research, the University of Tennessee; Core Student Award, Southern Appalachian Botanical Society. Last, but not least, I would like to thank my wife Shawna for standing strong during the past few years. Without her constant love and support I would not have gotten this far. To my beautiful daughter Madison, you arrived at just the right time to give me the spark I needed to finish up. I would also like to thank my parents, Mike and Shirley Murphy, for their love, financial assistance, and support. Finally, to all of my friends and family back home in Middle Tennessee who have gotten used to me not being around, thanks for understanding. ii ABSTRACT Gratiola (Plantaginaceae tribe Gratioleae) is a genus of ca. 33 wetland-adapted herbaceous species found mostly in temperate or tropical-montane regions of the Americas, Eurasia, and Australasia. The only worldwide taxonomic treatment of Gratiola was published more than 160 years ago and only a few representatives of the genus have been included in published molecular phylogenetic studies. The overall aim of this investigation was to provide a modern systematic study of Gratiola by determining the phylogenetic placement of Gratiola within the Gratioleae using chloroplast DNA sequence data (Chapter 2); examining the phylogenetic relationships, morphological character evolution, and biogeographical patterns within Gratiola using a combination of chloroplast DNA sequence data and morphology (Chapter 3); and conducting a taxonomic study of the Gratiola neglecta species complex, a group of four closely related and predominantly eastern North American species (Chapter 4). This dissertation is the accumulation of information from three original research papers. The first paper (Chapter 2) has been accepted for publication in Systematic Botany. The second paper (Chapter 3) will be submitted to Systematic Botany. The third paper (Chapter 4) has been published in the Journal of the Botanical Research Institute of Texas. The results from this study show (1) that Gratiola sensu lato (including Amphianthus, Fonkia, Sophronanthe, and Tragiola) is monophyletic and firmly embedded in a monophyletic Gratioleae and is sister to the Old World genera Hydrotriche and Limnophila; (2) that the 33 species (including four undescribed taxa) of Gratiola group into four major clades (Diandrae, Gratiola, Nibora, Sophronanthe) that are each morphologically cohesive and largely correspond to major biogeographic regions; and (3) that the Gratiola neglecta Complex includes four species (G. neglecta, G. floridana, G. graniticola, and G. quartermaniae), two of which constitute previously undescribed species that are morphologically and ecologically distinct. iii TABLE OF CONTENTS Chapter Page Chapter 1. Introduction to Plantaginaceae tribe Gratioleae and Gratiola………….. 1 Overview of the recently expanded Plantaginaceae………………………….............. 2 Overview of Plantaginaceae tribe Gratioleae………………………………………… 3 Overview of the Gratiola neglecta Species Complex………………………………... 4 Overview of Gratiola…………………………………………………………………. 5 Goals of the Project…………………………………………………………………… 7 Literature Cited……………………………………………………………………….. 9 Appendix…………………………………………………………………………….. 13 Chapter 2. Preliminary Phylogenetic Relationships of Plantaginaceae tribe Gratioleae with emphasis on the Monotypic Genus Amphianthus........................... 19 Abstract………………………………………………………………………............ 20 Introduction………………………………………………………………………….. 21 Materials and Methods………………………………………………......................... 23 Results……………………………………………………………….......................... 25 Discussion…………………………………………………….................................... 26 Taxonomic Treatment……………………………………………………….............. 30 Literature Cited………………………………………………………........................ 32 Appendix…………………………………………………………….......................... 37 Chapter 3. Two new species of Gratiola from eastern North America and an updated circumscription for Gratiola neglecta.......................................................................... 44 Abstract……………………………………………………………………................ 45 Introduction………………………………………………………….......................... 46 Materials and Methods………………………………………………......................... 46 Results and Discussion…………………………………………………….................47 Key to the species of the Gratiola neglecta complex…………………...................... 52 Taxonomic Treatment…………………………………………………….................. 53 Literature Cited………………………………………………………….................... 66 Appendix………………………………………………………………….................. 68 iv Chapter 4. Molecular Phylogenetic Relationships, Morphological Evolution, and Biogeography of Gratiola (Plantaginaceae) with new insights on the status of Braunblanquetia, Fonkia, Sophronanthe, and Tragiola…………..............................83 Abstract……………………………………………………………………................84 Introduction…………………………………………………………..........................85 Materials and Methods……………………………………………………................. 88 Results……………………………………………………………………….............. 91 Discussion……………………………………………………………….................... 94 Literature Cited………………………………………………………...................... 115 Appendix…………………………………………………………………................ 121 Chapter 5. General Conclusions and Future Directions…………............................ 147 Vita…………………………………………………………………………….............. 153 v LIST OF TABLES Table Page Chapter 1. Table 1.1. Genera of Plantaginaceae tribe Gratioleae, their geographic distribution, and approximate number of species…………………………………………………............. 14 Table 1.2. Comparison of the last worldwide treatment of