DNA Barcoding for Species Identification and Conservation of Caimans (Crocodilia: Alligatoridae)

Systematics has become an essential aspect of managing and conserving species from the order Crocodilia. All members of the group are listed in CITES appendices, and to control illegal traffic of animals and subproducts, we must be able to correctly assess the specific identity of the samples. Genetic DNA barcoding is a very efficient tool for species identification in the animal kingdom, based on the sequencing of a region of a mitochondrial gene, the Cytochrome oxidase subunit I (COI). Our principal aims were to design specific primers that allow obtaining this sequence from the genetic material of the caiman species and test the potential utility of barcoding in forensic studies, as well as verify the correct identification of different collections. We successfully obtained barcodes using our designed primers to amplify caiman samples, studying a fragment of 610 bp. We also compared sequences (N = 290) from public databases of all the species included in the Order Crocodilia, obtaining a tree that resulted in a similar current crocodilian phylogeny. The primers designed can be applied to obtain barcodes from samples of other crocodilian species, and this information can contribute significantly to forensic and systematic studies.