MOLLUSKS OF THE LATE PLEISTOCENE OÖLITIC FACIES OF THE MIAMI LIMESTONE IN THE MIAMI DADE COUNTY, SOUTH FLORIDA

The oölitic limestone that makes up the bedrock of Miami-Dade and parts of Broward County, Florida, is a relatively well studied formation, with poorly studied fossil content. No published systematic record of Pleistocene fossils in the Miami Limestone is available. Besides the basic knowledge of taxonomy and biodiversity of the mollusks, comparison with extant assemblages can yield important information about the biodiversity changes in southern Florida during the past ~130,000 years. Preliminary surveys of several localities, both previously described and new, within the Dade County yielded a record of diverse mollusks from over 28 families, 34 genera and 40 species. The preliminary findings of molluscan fossils have led to a new, unstudied and unpublished fossil locality with the second discovery of a possible Strombus costatus in the Miami Limestone. Miami Limestone fossils are being compared to recent South Florida mollusks indicating patterns of local diversification and extinction related to the minor changes in sea level and disappearance of certain habitats such as the rocky shore substrates that Cittarium pica once thrived on.