Paper No. 9
Presentation Time: 10:00 AM
ELEMENTS OF THE EXTANT EASTERN PACIFIC CONUS (NEOGASTROPODA) FAUNA IN THE NEOGENE OF THE DOMINICAN REPUBLIC AND SOUTHEASTERN UNITED STATES
HENDRICKS, Jonathan R., Department of Geology, San José State University, Duncan Hall 321, One Washington Square, San José, CA 95192 and SMITH, Ursula E., Paleontological Research Institution, 1259 Trumansburg Road, Ithaca, NY 14850, jonathan.hendricks@sjsu.edu
It has long been recognized that the Neogene molluscan fauna of tropical America included elements, termed "paciphiles" by W. P. Woodring in 1966, that are restricted today to the eastern Pacific Ocean. Here we report on Neogene occurrences of
Conus (cone snail) species from the Cibao Valley, Dominican Republic and the southeastern United States that are morphologically similar to species of
Conus that are found today in the eastern Pacific, but not the Caribbean. Some of these affinities are supported by phylogenetic analyses of a newly constructed total evidence dataset that incorporates molecular sequence data, morphometric data derived from eigenshape analysis, and traditional morphological character data from over 60 taxa.
The phylogenetic context of our study reveals that the factors that caused the extirpation of the paciphilic species in the Caribbean affected lineages within several different clades of Conus. In contrast, some other extant lineages of Conus have persisted in the Caribbean since the Miocene or Pliocene, despite being coeval members of the faunas that included the paciphilic species. We review the evolutionary histories of the paciphilic cone snail lineages in the broader context of paleoenvironmental changes associated with the Pliocene closure of the Central American Seaway. In this regard, particular attention is given to the spatio-temporal distributions of these paciphilic lineages, as well as their life histories and ecological associations.
