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Revision of the Melanoplus Scudderi (Orthoptera: Acrididae

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Revision of the Melanoplus Scudderi (Orthoptera: Acrididae Mississippi State University Scholars Junction Theses and Dissertations Theses and Dissertations 1-1-2015 Revision of the Melanoplus Scudderi (Orthoptera: Acrididae: Melanoplinae) Species Group and a Preliminary Investigation into the Grasshopper Fauna of the Grasslands of the Southeastern United States JoVonn Grady Hill Follow this and additional works at: https://scholarsjunction.msstate.edu/td Recommended Citation Hill, JoVonn Grady, "Revision of the Melanoplus Scudderi (Orthoptera: Acrididae: Melanoplinae) Species Group and a Preliminary Investigation into the Grasshopper Fauna of the Grasslands of the Southeastern United States" (2015). Theses and Dissertations. 3817. https://scholarsjunction.msstate.edu/td/3817 This Dissertation - Open Access is brought to you for free and open access by the Theses and Dissertations at Scholars Junction. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of Scholars Junction. For more information, please contact [email protected]. Automated Template A: Created by James Nail 2011 V2.02 Revision of the Melanoplus scudderi (Orthoptera: Acrididae: Melanoplinae) species group and a preliminary investigation into the grasshopper fauna of the grasslands of the southeastern United States By JoVonn Grady Hill A Dissertation Submitted to the Faculty of Mississippi State University in Partial Fulfillment of the Requirements for a degree in Doctor of Philosophy in Entomology in the Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology Mississippi State, Mississippi May 2015 Copyright by JoVonn Grady Hill 2015 Revision of the Melanoplus scudderi (Orthoptera: Acrididae: Melanoplinae) species group and a preliminary investigation into the grasshopper fauna of the grasslands of the southeastern United States By JoVonn Grady Hill Approved: ____________________________________ Richard L. Brown (Major Professor) ____________________________________ Gerald T. Baker (Committee Member) ____________________________________ Matt Eitel Dakin (Committee Member) ____________________________________ Daniel Otte (Committee Member) ____________________________________ Lisa Wallace (Committee Member) ____________________________________ Michael A. Caprio (Graduate Coordinator) ____________________________________ George M. Hopper Dean College of Agriculture and Life Science Name: JoVonn Grady Hill Date of Degree: May 8, 2015 Institution: Mississippi State University Major Field: Entomology Major Professor: Dr. Richard Brown Title of Study: Revision of the Melanoplus scudderi (Orthoptera: Acrididae: Melanoplinae) species group and a preliminary investigation into the grasshopper fauna of the grasslands of the southeastern United States Pages in Study: 213 Candidate for Doctor of Philosophy The Melanoplus scudderi species group, when erected by Blatchley, contained six species. The revision of the group presented here describes 21 new species and establishes the Melanoplus carnegiei group, all of which are associated with grasslands in the Southeast. Analysis of DNA barcoding data, suggest that the technique does not adequately delineate species based on the morphological concepts presented here, but did produce three broad mitochondrial DNA clades that correspond to the Apalachicola and Mississippi River discontinuity phylogeographic pattern displayed by several other organisms in the Southeastern United States. This pattern is attributed to vicariant events resulting from Pleistocene glaciation. A hypothetical evolutionary history of the Scudderi and Carnegiei groups is presented. Natural grasslands historically covered a significant portion of the southeastern United States. These grasslands contribute significantly to the biodiversity of the region with many endemic or rare species inhabiting them. Grasshoppers are important components of temperate grassland ecosystems, but no comprehensive review of the grasshopper fauna of southeastern grasslands had previously been conducted. Here a review of the regional fauna was conducted. In total, 211 grasshopper species have been documented in the Southeast, with 111 species (53%) being endemic to natural grasslands. Of particular note, 74 species (34% of the regional fauna) are endemic to the longleaf pine ecosystem. Many of the non-endemic grasshopper species inhabiting grasslands in the region are disjunct from larger populations west of the Mississippi River, presenting interesting biogeographic distributions. Additionally, a cluster analysis of grasshopper community composition from several types of grasslands in the region supports the faunal distinctiveness of the different types grasslands in the region. ACKNOWLEDGEMENTS I thank Dr. Richard Brown for serving as my major professor and providing insightful taxonomic assistance, Dr. Dan Otte for graciously handing this project to me, Dr. Lisa Wallace for her assistance with the molecular aspects of the study, Dr. Matt Dakin and Dr. Gerry Baker for their guidance as committee members and comments on this manuscript. Additionally, I thank the late Dr. Irving Cantrall who collected many of the specimens that this revision was based on. Specimens collected by JGH were obtained under permits from the Arkansas Natural Heritage Commission, Florida State Parks, Georgia Department of Natural Resources, Mississippi Department of Wildlife Fisheries and Parks, North Carolina Division of Parks and Recreation, The National Park Service, The Nature Conservancy, South Carolina State Parks, Tennessee Division of Natural Areas, and Texas Parks and Wildlife. I thank Mark O’Brien of the University of Michigan Museum of Zoology, Jason Weintraub of the Academy of Natural Sciences of Drexel University, Steven Krauth, of the Wisconsin Insect Research Collection, Matt Dakin of Auburn University Museum of Natural History, Paul Skelley of the Florida State Collection of Arthropods, Bob Blinn of the North Carolina State Insect Collection for preparing loans of material examined in this study. Additionally, I thank Justin Luke, Jordan Gesell, and Charlotte Chesenut for assisting with specimen preparation and locality data entry. This research received financial support from the Orthopterists’ Society, the William H. Cross Expedition Endowment in the Mississippi State University ii Development Foundation, the Georgia Department of Natural Resources, and the Mississippi Agricultural and Forestry Experiment Station. This research was supported by the National Institute of Food and Agriculture, under Project No. MIS-012040. iii TABLE OF CONTENTS ACKNOWLEDGEMENTS ................................................................................................ ii LIST OF TABLES ............................................................................................................ xii LIST OF FIGURES ......................................................................................................... xiii CHAPTER I. INTRODUCTION .............................................................................................1 Introduction ........................................................................................................1 Background on the genus Melanoplus .........................................................2 Literature Cited ..................................................................................................4 II. REVISION OF THE MELANOPLUS SCUDDERI (ORTHOPTERA:ACRIDIDADE) SPECIES GROUP .........................5 Introduction ........................................................................................................5 Methods..............................................................................................................7 Morphological study ....................................................................................7 Species delimitation .....................................................................................9 Molecular techniques ...................................................................................9 Results ..............................................................................................................12 Comparison of the groups ..........................................................................12 Diagnosis of the Melanoplus scudderi species group ................................13 Structural Characters ............................................................................13 Phallic Structures .................................................................................14 Coloration ............................................................................................14 Species accounts ........................................................................................15 Melanoplus scudderi Uhler (Figs. 1A-J, 2A-B, 3, 4A-B) ....................15 Male Measurements (mm) .............................................................15 Female Measurements (mm)..........................................................15 Diagnosis........................................................................................15 Lectotype here designated..............................................................16 Other specimens examined ............................................................16 Distribution ....................................................................................32 Habitat ............................................................................................32 Remarks .........................................................................................32
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