VASCULAR FLORA OF THE GUÁNICA DRY FOREST, PUERTO RICO by Omar A. Monsegur Rivera A thesis submitted in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE in BIOLOGY UNIVERSITY OF PUERTO RICO MAYAGÜEZ CAMPUS 2009 Approved by: _______________________________ _____________________ Duane A. Kolterman, PhD Date Member, Graduate Committee _______________________________ _____________________ Jesús D. Chinea, PhD Date Member, Graduate Committee _______________________________ _____________________ Gary J. Breckon, PhD Date President, Graduate Committee _______________________________ _____________________ Nilda E. Aponte, PhD Date Representative of Graduate Studies _______________________________ _____________________ Nanette Diffoot Carlo, PhD Date Chairperson of the Department Abstract The systematic review of the Guánica Forest Reserve flora indicates that it consist of 460 accepted species, plus another 258 species that require confirmation. The number of unconfirmed records is greater than that of other dry forest areas in Puerto Rico, suggesting that further fieldwork and herbaria work is needed. A total of 102 new record are included as part of this work, including Sansevieria concinna as a new record for the island of Puerto Rico and the Caribbean. The Guánica Forest is a major depository of the Puerto Rican and Caribbean dry forest plant diversity. Three of the endemics are restricted to the Forest and do not occur elsewhere in the world. Reynosia vivesiana and Zephyranthes proctorii are identified as species that should be considered to be listed as endangered species. In general the number of exotics and naturalized species is relatively low. Nevertheless, Haematoxylon campechianum and Sansevieria concinna are examples of the species that deserve further study as potential invasive species within the Forest. ii Resumen La evaluación sistemática de la flora de la Reserva Forestal de Guánica indica que está consiste de 460 especies aceptadas, con otras 258 especies que requieren ser confirmadas. El número de reportes sin confirmar es mayor que otras areas en Puerto Rico, sugiriendo que se require de más trabajo de campo y herbario. Un total de 102 nuevos reportes son incluidos como parte de este trabajo, incluyendo Sansevieria concinna como un nuevo registro para la isla de Puerto Rico y el Caribe. El Bosque de Guánica es un depositorio principal de la diversidad de plantas de bosque seco de Puerto Rico y el Caribe. Tres de las species endémicas están restringidas al Bosque y no se encuentran en ningún otro lugar del planeta. Se identifica a Reynosia vivesiana y Zephyranthes proctorii como especies que deben consideradas para ser listadas como especies en peligro de extinción. En general el número de especies naturalizadas y exóticas es relativamente bajo. Sin embargo, Haematoxylon campechianum y Sansevieria concina son ejemplos de especies que merecen más estudio por su potencial como especies invasoras dentro del Bosque. iii Copyright 2009 by Omar A. Monsegur Rivera I grant the University of Puerto Rico the non-exclusive right to use this work for the University’s own purposes and to make single copies of this work available to the public on a not-for-profit if copies are otherwise unavailable. iv Acknowledgments I want to thanks all the members of my graduate commette and the botany professors of the University of Puerto Rico at Mayagüez. All of them have contributed to what I have learned during all these years. I specially recognize Dr. Gary J. Breckon for his trust and patience. I must mention the support of Pedro Acevedo from the Smithsonian Institution. His assistance was critical during my visit to the US herbarium. He also made accessible all the data of his collections from Guánica. Mark Strong and Vicky Funk also helped me during my intership at the Smithsonian. Frank Axelrod kindly provided the unpublished manuscript of his Vademecum to the Vascular Plants of Puerto Rico. The directors of the herbaria in Puerto Rico (SJ, UPR and UPRRP) provided the opportunity to examine the vouchers from the Guánica Forest. Jeanine Vélez (MAPR) helped me with the management of the Brahms database. Nestor Pérez Molièr (NY) always responded immediately to any request for images or specimen data. My friends Carlos C. Martínez and Amelia Merced were part of that small, but persistent group of students who decided to explore the unknown. Both of them were part of my first steps into botany. There was an extensive amount of field work on the Guánica Forest Reserve that would not be possible without the assistance of numerous graduate and undergraduate students; Javier Román and Ilianet Morales were always there. Also, I want to thank all my former partners at the Puerto Rican parrot project: Iván Llerandi, Jesús Ríos, Ana Estrella, Brian Ramos, Jong Piel Banch and Ricardo Valentín. You all know that more than friends, we are a family. There is a grumpy Puerto Rican botanist who v deserves all my admiration, Mr. José Sustache Sustache. Thanks Sustache for making me laugh and for your unconditional friendship. The Department of Natural and Environmental Resources of Puerto Rico provided the collecting permits for this research. Also Mr. Miguel Canals provided access to the different areas of the Forest, helped me to locate some of the rare species and took me to pristine areas. The US Fish and Wildlife Service, Boquerón Field Office provided time to complete the revision of the manuscript and to do herbarium work. I will always be grateful for the support and the input of my partners at Boquerón. Thanks Carlitos for sharing your knowledge about the natural history and management of the Guánica Forest. To Jan Paul for your friendship and patience during the design of the maps. Finally, I am gratefull to all my family for their patience and love. Especially to Bárbara Sanchéz for being there and understanding why all our vacations ended up collecting plants. Thanks for helping me collect and getting pictures of the never-ending beauty of our loved Puerto Rico. vi Table of contents Abstract ........................…………………………………………………………… ii Resumen ........……………………………………………..………………………. iii Acknowledgments ....……………………………………...……………………... v Table of contents ........…………………………………………………………….. vii List of tables ...........……………………………………………………………….. viii List of figures .........………………………………………………………………... ix List of appendices .......…………………………………………………………..… x Introduction ............………………………………………………………………... 1 Objectives .......................…………………………………………………………... 5 Litterature review ...........………………………………………………………….. 6 Methodology .......………………………………………………………………….. 10 Results .........……………………………………………………………………...... 17 Discussion ......…………………………………………………………………........ 19 Summary of results ....…………………………………………………………...... 28 Conclusions .....…………………………………………………………………....... 29 Recommendations ……………………………………………………………….... 30 Literature cited ......………………………………………………………………... 31 Tables ........................………………………………………………………………. 38 Figures ............…………………………………………………………………....... 55 Appendices ..……………………………………………………………….............. 63 vii List of tables Table 1. Summary of the collecting days and the number of species collected, and the cumulative number of species not previously collected per collecting trip. ………..... 39 Table 2. Summary of the names attributed to the flora of the Guánica Forest Reserve. ……………………………………………………………………………………..… 41 Table 3. New vascular plants records for the Guánica Forest Reserve. ……………………..... 42 Table 4. Comparison between the proportion of unconfirmed taxa among the Guánica Forest Reserve, Mona Island, Susúa Forest and Vieques Island. ………………...…. 46 Table 5. Summary of regional endemics reported for the flora of the Guánica Forest Reserve. ……………………………………………………………………………..…. 47 Table 6. Species designated as critical elements by the Department of Natural and Environmental Resources (CE) or listed by the US Fish and Wildlife Service (FL). ………………………………………………………………………………..…. 48 Table 7. Comparison of the percent of the flora corresponding to Critical Elements and Federally Listed species between some natural areas in Puerto Rico. ……………….….... 50 Table 8. Rare species occurring within the Guánica Forest Reserve that deserve further study and should be considered to be designated as Critical Elements by Department of Natural and Environmental Resources or protected by U.S. Fish and Wildlife Service. ………………………………………………………………………..... 51 Table 9. Species confirmed within the flora of the Guánica Forest Reserve and known only from collections prior to 1951. …………………………………………….… 52 Table 10. Introduced and/or naturalized species within the Guánica Forest Reserve. ……………………………………………………………………………………...… 53 viii List of figures Figure 1. Map of the location of the Guánica Forest Reserve, including the new boundaries of the West and East Units. ……………………………………………. 56 Figure 2. Map of the trails and collecting areas of the the Guánica Forest Reserve “East Unit”. ………………………………………………………………….… 57 Figure 3. Map of the trails and collecting areas of the the Guánica Forest Reserve “West Unit”. …………………………………………………………….……... 58 Figure 4. Map of the surveyed areas and collecting points in the Guánica Forest Reserve “East Unit”. …………………………………………………………….. 59 Figure 5. Map of the surveyed areas and collecting points in the Guánica Forest Reserve “West Unit”. ……………………………………………………………. 60 Figure 6. Cumulative number of species during the collecting period. …..…………….. 61 Figure 7. Distribution