CSIRO PUBLISHING Invertebrate Systematics, 2018, 32, 689–702 https://doi.org/10.1071/IS17059 The Pleurobemini (Bivalvia : Unionida) revisited: molecular species delineation using a mitochondrial DNA gene reveals multiple conspecifics and undescribed species Kentaro Inoue A,I, David M. Hayes B, John L. Harris C, Nathan A. Johnson D, Cheryl L. Morrison E, Michael S. Eackles E, Tim L. King E, Jess W. JonesF,G, Eric M. HallermanF, Alan D. Christian C,H and Charles R. Randklev A ANatural Resources Institute, Texas A&M University, Dallas, TX 75252, USA. BDepartment of Biological Sciences, Eastern Kentucky University, Richmond, KY 40475, USA. CDepartment of Biological Sciences, Arkansas State University, Jonesboro, AR 72467, USA. DUS Geological Survey, Wetland and Aquatic Research Center, Gainesville, FL 32653, USA. EUS Geological Survey, Leetown Science Center, Kearneysville, WV 25430, USA. FDepartment of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, USA. GUS Fish and Wildlife Service, Blacksburg, VA 24061, USA. HSchool for the Environment, University of Massachusetts, Boston, MA 02125, USA. ICorresponding author. Email:
[email protected] Abstract. The Pleurobemini (Bivalvia: Unionida) represent approximately one-third of freshwater mussel diversity in North America. Species identification within this group is challenging due to morphological convergence and phenotypic plasticity. Accurate species identification, including characterisation of currently unrecognised taxa, is required to develop effective conservation strategies because many species in the group are imperiled. We examined 575 cox1 sequences from 110 currently recognised species (including 13 Fusconaia and 21 Pleurobema species) to understand phylogenetic relationships among pleurobemine species (mainly Fusconaia and Pleurobema) and to delineate species boundaries.