Freshwater mussels of the family Unionidae, also known as naiads, have inhabited fresh waters around the world for the last 400 million years. Here in Texas, the presence of these unique mollusks ensures our water quality, helps support the worldwide pearl industry, and, in a quirk of history, influenced the founding of San Angelo. Yet their continued survival is by no means certain, due to overharvesting, environmental degradation, and the rapid spread of exotic mussel species.
To help professional biologists and amateur naturalists know and preserve these mollusks, this book provides baseline reference material for all 52 species of freshwater mussels in Texas. It focuses particularly on the unionids, with brief descriptions of other freshwater bivalves. A typical entry includes the following information:
Scientific and common names
Distribution (with a range map)
Size / Shell / Shell teeth
External color / Internal color
Soft tissues / Habitat / Spawning
Glochidia / Hosts
Color photos illustrate each species. In addition to the descriptions, the authors offer general discussions of freshwater mussel anatomy, biology, ecology, and commercial uses.
Robert G. Howells works at the Texas Parks and Wildlife Heart of the Hills Research Station in Ingram. Dr. Raymond W. Neck worked at the Houston Museum of Natural Science. Dr. Harold D. Murray teaches in the Biology Department at Trinity University in San Antonio.
Acknowledgments Introduction About This Guide Anatomy Shell Soft Tissues Shell Muscles Mantle Foot Other Soft Tissues Biology Reproduction Sexuality Maturity (Size and Age) General Mode of Reproduction Spawning, Egg Deposition, and Incubation Spawning Season Glochidia and Parasitism Juveniles Habitat Water Body Types Bottom Types Current Water Depth Water Chemistry and Clarity Aquatic Vegetation Associated Animals Natural Transport and Relocation Transport and Relocation by Man Feeding and Food Growth Behavior Movement Over-wintering and Drought Tolerance Responses to Stimuli Parasites, Diseases, Predators, Abnormalities Ecology Abundance Factors Affecting Reproduction Factors Affecting Natality, Recruitment, and Mortality Importance in the Ecosystem Exploitation and Commercial Importance Prehistorical and Historical Harvest Current Harvest in Texas Collection Methods, Gear, and Regulations Uses Shells Pearls Meat Live Pearl-culture Mussels Biogeography in Texas Freshwater Mussels (Family: Unionidae) Threeridge (Amblema plicata) Giant Floater (Anodonta grandis) Paper Pondshell (Anodonta imbecillis) Flat Floater (Anodonta suborbiculata) Rock-Pocketbook (Arcidens confragosus) Ouachtta Rock-Pocketbook (Arkansia wheeleri) Tampico Pearlymussel (Cyrtonaias tampicoensis) Spike (Elliptio dilatata) Texas Pigtoe (Fusconaia askewi) Wabash Pigtoe (Fusconaia flava) Triangle Pigtoe (Fusconaia lananensis) Round Pearlshell (Glebula rotundata) Texas Fatmucket (Lampsilis bracteata) Plain Pocketbook (Lampsilis cardium) Louisiana Fatmucket (Lampsilis hydiana) Sandbank Pocketbook (Lampsilis satura) Yellow Sandshell (Lampsilis teres) White Heelsplitter (Lasmigona complanata) Fragile Papershell (Leptodea fragilis) Pond Mussel (Ligumia subrostrata) Washboard (Megalonaias nervosa) Threehorn Wartyback (Obliquaria reflexa) Southern Hickorynut (Obovaria jacksoniana) Bankclimber (Plectomerus dombeyanus) Louisiana Pigtoe (Pleurobema riddelli) Texas Hornshell (Popenaias popei) Texas Heelsplitter (Potamilus amphichaenus) Pink Papershell (Potamilus ohiensis) Bleufer (Potamilus purpuratus) Salina Mucket (Potamilus salinasensis) Southern Mapleleaf (Quadrula apiculata) Golden Orb (Quadrula aurea) Rio Grande Monkeyface (Quadrula couchiana) Smooth Pimpleback (Quadrula houstonensis) Western Pimpleback (Quadrula mortoni) Wartyback (Quadrula nodulata) Texas Pimpleback (Quadrula petrina) Pimpleback (Quadrula pustulosa) Mapleleaf (Quadrula quadrula) False Spike (Quincuncina mitchelli) Squawfoot (Strophitus undulatus) Lilliput (Toxolasma parvus) Texas Lilliput (Toxolasma texasensis) Pistolgrip (Tritogonia verrucosa) Mexican Fawnsfoot (Truncilla cognata) Fawnsfoot (Truncilla donaciformis) Texas Fawnsfoot (Truncilla macrodon) Deertoe (Truncilla truncata) Tapered Pondhorn (Uniomerus declivis) Pondhorn (Uniomerus tetralasmus) Little Spectaclecase (Villosa lienosa) Other Bivalve Mollusk Families Found in Fresh Waters Family: Corbiculidae Asian Clam (Corbicula sp(p).) Carolina Marshclam (Polymesoda caroliniana) Family: Mactridae Atlantic Rangia (Dreissena polymorpha) Family: Dreissenidae Zebra Mussel (Dreissena polymorpha) Dark Falsemussel (Mytilopsis leucophaeata) Family: Sphaeriidae Fingernail Clams Glossary References Index Appendix I: Gulf Mapleleaf (Quadrula nobilis) Appendix II: Color Plates