Abstract
Recent fossil shell mining for a new rail line in the Orlando area of Orange County, Florida has uncovered two species of the ellobioid genus Carychium O. F. Müller, 1773 in a bed of freshwater marl from the Lower Pleistocene Nashua Formation. To taxonomically interpret these finds, the well-preserved shells were imaged via high-resolution X-ray tomography (micro-CT) to view significant internal diagnostic characters such as the columellar configuration and the degree of lamellar sinuosity and their relationship in context to the entire shell. The image data are compared to that of type material and extant and fossil Carychium species inhabiting the SE USA, Mexico, Central America, and Jamaica. Based on these results, the species Carychium floridanum G. H. Clapp, 1918 and Carychium nashuaensesp. nov. are identified from fossil shells dating from the Early Pleistocene. This work documents the first fossil members of C. floridanum and the first fossil Carychium from the SE USA.
Subject
Animal Science and Zoology,Ecology, Evolution, Behavior and Systematics
Reference29 articles.
1. First Floridians and Last Mastodons: The Page-Ladson Site in the Aucilla River
2. Descriptions of thirty supposed new species and varieties of land and fluviatile shells of Jamaica, with observations on some shells already described.;Chitty;Contributions to Conchology,1853
3. New southern forms of Carychium and Thysanophora.;Clapp;The Nautilus,1918
4. Avian Community, Climate, and Sea-Level Changes in the Plio-Pleistocene of the Florida Peninsula
5. Recent advances in the study of long-distance dispersal of aquatic invertebrates via birds