Molluscan Paleontology of the Chesapeake Miocene »

Authors Edward J. Petuch and Mardie Drolshagen are professors in the Department of Geosciences at Florida Atlantic University in Boca Raton.

The Chesapeake Miocene will always be considered a paleontological treasure. Given the richness and accessibility of the Maryland and Virginia Miocene shell beds, it seems remarkable that very few people have ever described new species from these strata over the past 185 years. Until now. Integrating elements from paleontology, geology, environmental science, and ecology, Molluscan Paleontology of the Chesapeake Miocene assembles previous research and the authors’ experience into a synoptic field guide.

The most complete compendium of Miocene species created since 1904, this long-awaited resource lists nearly 500 species. It contains illustrations of 260 species, including more than 60 not found in any previous book and 26 newly discovered. It describes Chesapeake molluscan faunas in terms of local geology, paleoceanography, and marine paleobiology. Organized by stratigraphic geology, the book covers fossils of the Eastover, St Mary’s, Choptank, and Calvert Formations. It illustrates 24 collecting sites and fossil exposures, showing details of in situ specimens, along with maps of 4 Miocene paleoseas and detailed stratigraphic columns for Maryland and northern Virginia. The text is accompanied by a CD-ROM with color illustrations of the forty known species of ecphora shells. Armed with these, you should be able to identify the species found in the amazingly rich shell beds of the Chesapeake Bay area.

Acknowledgments ix

Authors xi

Introduction: Fossil Shell Collecting in the Maryland and Virginia Miocene xiii

Chapter 1 Miocene Seas of the Chesapeake Bay Area 1

The Salisbury Sea 2

The Calvert Subsea and Its Environments 3

The Patuxent Subsea and Its Environments 5

The St. Mary's Subsea and Its Environments 8

The Albemarle Sea 9

The Rappahannock Subsea and Its Environments 12

Miocene Marine Biogeography 16

Chapter 2 Geologic Framework of the Maryland and Virginia Miocene 21

The Calvert Formation and Its Members 24

The Choptank Formation and Its Members 26

The St. Mary's Formation and Its Members 28

The Eastover Formation and Its Members 30

Chapter 3 Ecphoras of the Maryland and Virginia Miocene 35

Evolutionary Patterns of the Ecphoras 39

Ecology of the Ecphoras 41

Ecphora Biostratigraphy 43

Chapter 4 Fossils of the Calvert Formation 47

Shells of the Fairhaven Member 47

Shells of the Plum Point Member 49

Shells of the Calvert Beach Member 57

Systematic List of Calvert Mollusks 57

Calvert Formation 59

Chapter 5 Fossils of the Choptank Formation 65

Shells of the St. Leonard Member 65

Shells of the Drumcliff Member 69

Shells of the Boston Cliffs Member 73

Systematic List of Choptank Mollusks 74

Choptank Formation 74

Chapter 6 Fossils of the St. Mary's Formation 79

Shells of the Conoy Member 79

Shells of the Little Cove Point Member 79

Shells of the Windmill Point Member 83

Shells of the Chancellor Point Sandstone 91

Systematic List of St. Mary's Mollusks 93

St. Mary's Formation 93

Chapter 7 Fossils of the Eastover Formation 101

Shells of the Claremont Manor Member 101

Shells of the Cobham Bay Member103

Systematic List of Eastover Mollusks 109

Eastover Formation 109

References 115

Systematic Appendix: Descriptions of New Species, Subspecies, and Genera 119

New Species and Subspecies 119

New Genera 120

Index 141