The University of Southern Mississippi The Aquila Digital Community Dissertations Summer 8-2008 Review of the Genus Polycheria Haswell, A Symbiotic Group of Amphipods (Crustacea: Dexaminidae) with Descriptions of New Species from Florida, the Caribbean Sea, and the Indo-Pacific Region John Milton Foster University of Southern Mississippi Follow this and additional works at: https://aquila.usm.edu/dissertations Part of the Aquaculture and Fisheries Commons, and the Marine Biology Commons Recommended Citation Foster, John Milton, "Review of the Genus Polycheria Haswell, A Symbiotic Group of Amphipods (Crustacea: Dexaminidae) with Descriptions of New Species from Florida, the Caribbean Sea, and the Indo-Pacific Region" (2008). Dissertations. 1142. https://aquila.usm.edu/dissertations/1142 This Dissertation is brought to you for free and open access by The Aquila Digital Community. 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The University of Southern Mississippi REVIEW OF THE GENUS POLYCHERIA HAS WELL, A SYMBIOTIC GROUP OF AMPHIPODS (CRUSTACEA: DEXAMINIDAE) WITH DESCRIPTIONS OF NEW SPECIES FROM FLORIDA, THE CARIBBEAN SEA, AND THE INDO-PACIFIC REGION by John Milton Foster A Dissertation Submitted to the Graduate Studies Office of The University of Southern Mississippi in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Approved: August 2008 The University of Southern Mississippi REVIEW OF THE GENUS POLYCHERIA HASWELL, A SYMBIOTIC GROUP OF AMPHIPODS (CRUSTACEA: DEXAMINIDAE) WITH DESCRIPTIONS OF NEW SPECIES FROM FLORIDA, THE CARIBBEAN SEA, AND THE INDO-PACIFIC REGION by John Milton Foster Abstract of a Dissertation Submitted to the Graduate Studies Office of The University of Southern Mississippi in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy August 2008 ABSTRACT REVIEW OF THE GENUS POLYCHERIA HASWELL, A SYMBIOTIC GROUP OF AMPHIPODS (CRUSTACEA: DEXAMINIDAE) WITH DESCRIPTIONS OF NEW SPECIES FROM FLORIDA, THE CARIBBEAN SEA, AND THE INDO-PACIFIC REGION by John Milton Foster Systematics and taxonomy of the dexaminid amphipod genus Polycheria Haswell (Dexamindae: Amphipoda), whose members are cosmopolitan associates of tunicates and sponges, are confused. This is due in large part to the many inadequate and incomplete descriptions and poorly some executed illustrations, especially for the early studies on the group. Previously, 22 nominal species or forms have been described or designated in the literature. The purpose of this study is to critically review and clarify the systematics of this enigmatic genus. Based on personal collections and on specimens from museums, five new species are designated and 22 species or forms are re-described. All the species and forms of Polycheria are illustrated and a dichotomous key constructed for their identification. For cladistic analysis, a suite of 77 morphological characters were selected and coded in DELTA. Analysis was preformed using PAUP, including strict consensus, 50% majority rule, and decay indices. The resulting best tree indicated that Polycheria is a monophyletic group characterized by (1) subchelate pereopods 3-7; (2) absence of palp on maxilla on the mandibles; (3) lower lip inner and outer lobes well developed; (4) a one-articulate palp on maxilla 1, and (5) and a 4-articulate palp on the maxiiliped. The hypotheses presented, based on the currently understood ii distribution of Polycheria, the current and historical position of the continents and major oceanic currents, and the majority rule consensus tree generated from 77 parsimonious characters, indicates that (1) Polycheria had its origins in the Southern Ocean between Antarctica and the Australia/New Zealand area; (2) the dispersal of the ancestral Polycheria genotype occurred along at least two tracks - a circumpolar track eastward around Antarctica, driven by the Antarctic Circumpolar Current and along a northern track around New Zealand, along the east coast of Australia, into the Australasian region, and eventually northward to the Sea of Japan; and (3) the Antarctica peninsula appears to be an area of high speciation from which dispersals eastward into the Indian Ocean and possibly Australia originated. iii ACKNOWLEDGMENTS I would like to express my gratitude to Brent P. Thoma of the University of Louisiana, Lafayette, formerly of The University of Southern Mississippi (USM), for his tireless field work, companionship, and assistance during this study and to Dr. Jerry A. McLelland (USM) for his critical assistance and generosity. I am indebted to Ms. Sara LeCroy, Museum Director, Gulf Coast Research Laboratory (USM) for making the arrangements for the loan of specimens from museums around the world. Her encouragement, counsel and contacts were crucial to this project. I thank Mrs. Cathy Schloss of the Caylor Library, Gulf Coast Research Laboratory (USM) who provided friendly and efficient interlibrary loan service. Gratitude is due to my doctoral committee members, Dr. Richard W. Heard, Dr. Robin Overstreet, and Dr. Jeff Lotz (USM), and Dr. James D. Thomas (Nova Southeastern University) for their encouragement and guidance during this research and to Drs. Heard, Thomas, and Overstreet for providing financial support for travel to the Florida Keys, the Cayman Islands, and Belize. Additionally, I thank the curators of the museums that kindly made specimens available: Smithsonian Institution (National Museum of Natural History), Washington, D.C.; The Australian Museum, Sydney; The Zoological Museum, Copenhagen; Museum fur Naturkunde, Berlin; The British Museum (Natural History), London; and the Southeast Regional Taxonomic Center, South Carolina Department of Natural Resources, Charleston. Also, I thank Dr. Michael Gable (East Connecticut State University) and Dr. Dirk Platvoet (University of Amsterdam) for iv material making material available from Puerto Rico. Other personal material was made available from Panama by Sara E. LeCroy and from Indonesia by Dr. James D. Thomas. Aspects of this research were supported by grant # OPP-0442769 from the U.S. National Science Foundation awarded to James B. McClintock and Charles D. Amsler. Finally, I extend my appreciation to my mother Mrs. Hazel Parker Foster for her support of this research and to Dr. Richard W. Heard for his friendship, generosity and mentorship over the past 20 years. To those additional persons not mentioned by name, you have my sincere gratitude. v TABLE OF CONTENTS ABSTRACT n ACKNOWLEDGMENTS iv LIST OF ILLUSTRATIONS viii LIST OF TABLES xi CHAPTER I. PROBLEM AND BACKGROUND 1 Introduction Objectives of study Significance of the study II. HISTORICAL REVIEW 9 The Family Dexaminidae Leach, 1814 The history ofPolycheria Has well systematics Review of the ecology and symbiotic behavior of Polycheria species HI. MATERIALS AND METHODS 26 Notes on materials The study area Field methods Laboratory methods Phylogenetic methods IV. SYSTEMATIC SECTION 40 Introduction Diagnosis of Polycheria Western Atlantic species South Atlantic/Southern Ocean species and forms Indo-West Pacific Ocean/Australian/New Zealand species Northeastern Pacific Ocean species Key to the species and forms of Polycheria Haswell vi V. CLADISTIC ANALYSIS AND BIOGEOGRAPHY 192 Results Discussion VI SYMBIOSIS AND ECOLOGY OF POLYCHERIA SP. A IN ST. JOSEPH BAY, FLORIDA 205 APPENDDCES 216 REFERENCES 242 vii LIST OF ILLUSTRATIONS Figure 1. Map depicting the type localities of the species and forms of Polycheria, including the new species described herein and the related genus Tritaeta 4 2. St. Joseph Bay, Florida indicating the Blacks Island study area 30 3. Collection stations in the vicinity of Blacks Island, St. Joseph Bay, Florida ... 31 4. Distribution of Polycheria collections from the Gulf of Mexico and the Caribbean Sea 41 5. Polycheria sp. A, new species 50 6. Polycheria sp. A, new species 51 7. Polycheria sp. A, new species 52 8. Polycheria sp. B, new species 60 9. Polycheria sp. B, new species 61 10. Polycheria sp. B, new species 62 11. Polycheria sp. C, new species 65 12. Polycheria sp. D, new species 69 13. Polycheria acanthocephala Schellenberg, 1931 75 14. Polycheria acanthocephala Schellenberg, 1931 76 15. Polycheria antarctica form acanthopoda Thurston, 1974 81 16. Polycheria antarctica form acanthopoda Thurston, 1974 82 17. Coxal plates 1 and 4 of Polycheria antarctica form dentata, form gracilipes, form similis, form bidens, form macrophthalama, and form tenuipes 87 18. Polycheria antarctica (Stebbing, 1875) 88 viii 19. Polycheria antarctica (Stebbing, 1875) 89 20. Polycheria antarctica form cristata Schellenberg, 1931 94 21. Polycheria antarctica form cristata Schellenberg, 1931 95 22. Polycheria antarctica form dentata Schellenberg, 1931 100 23. Polycheria antarctica form dentata Schellenberg, 1931 101 24. Polycheria antarctica form gracilipes Schellenberg, 1931 107 25. Polycheria antarctica form intermedia Stephenson, 1947 Ill 26. Polycheria antarctica form kergueleni (Stebbing, 1899) 117 27. Polycheria antarctica form macrophthalma Schellenberg, 193 123 28. Polycheria antarctica form nudus Holman and Wailing, 1983 126 29. Polycheria antarctica form similis Schellenberg, 1931 129 30. Polycheria amakusaensis Hirayama, 1984 134 31. Polycheria amakusaensis Hirayama, 1984 135 32. Polycheria atolli Walker, 1905 139 33. Polycheria brevicornis Haswell, 1879 142 34. Polycheriajaponica Bulycheva,