The Taxonomic Status of Florida Caiman: A Molecular Reappraisal

The state of Florida has the world's highest diversity of established nonnative reptiles, including snakes, lizards, turtles, and crocodilians, most of them introduced from the pet trade. The Spectacled Caiman (Caiman crocodilus) is the only nonnative crocodilian established in Florida, with the earliest date of introduction in 1950. Despite its likely origin being Colombia, the taxonomic identity of the subspecies occurring in Florida remains unknown. We report the first study that resolves the taxonomic status of the population of Ca. crocodilus in Florida based on molecular analysis of samples collected from the 1970s to 2013. We also investigate the probable origin of this population as well as the specimens of the Dwarf Caimans, Paleosuchus palpebrosus and Paleosuchus trigonatus, which have been collected in Florida. We identified only one lineage of Ca. crocodilus in Florida, corresponding to Caiman crocodilus fuscus, and our results indicate the Magdalena River basin in Colombia as the most likely area of origin. We also correct the identification of Paleosuchus recorded in Florida and identify the Guiana Shield, and specifically Guyana, as the most likely region from which these specimens were introduced.