Forensic Genetic Analyses of Melanistic Iguanas Highlight the Need to Monitor the Iguanid Trade

SIMPLE SUMMARY: The illegal pet trade remains an ongoing, substantial threat to wild populations, especially small insular populations, and can even lead to extinction. Fraudulent activity within the global reptile trade is known to occur, but its identification through forensic applications depends on knowledge of diversity within wild populations. In this study, we assessed the geographic origin of melanistic iguanas (Iguana iguana), which are only found in nations that have never authorized legal export of live animals. Analysis of genetic data from two pet iguanas in the USA flag these as originating from Saba or Montserrat, from which no export permits have ever been issued, confirming their illegal origin. Despite the international trade in I. iguana, in which tens- if not hundreds of thousands of specimens are traded each year, only a handful of individuals have been genetically assessed. Our work highlights the utility of applying forensic genetic techniques to this trade in order to track and discourage illegal activity. ABSTRACT: Lizards within the Iguana iguana species complex are among the most common reptilian pets, with the widest natural geographic range among iguanids. Deep phylogenetic divergence distinguishes multiple mitochondrial clades, and several taxonomic changes have recently been proposed. These small populations, typically island endemics, are threatened by numerous factors, including the international pet trade. Recent investigations reveal the absence of required CITES permits for lawful export of animals, providing evidence of ongoing illegal trade. Additional monitoring of trade in iguanas can be achieved through the application of forensic molecular techniques. In this study, two captive melanistic iguanas were genotyped for molecular markers for which geographic distributions of alleles have been established. Mitochondrial sequencing indicates that both animals carry a haplotype known to originate from the islands of Saba and Montserrat, populations taxonomically proposed to be Iguana melanoderma. Genotypes at 15 microsatellite loci are equally consistent with this origin, given the results of a principal component analysis. This first forensic genetic assessment within the extensive I. iguana pet trade highlights the presence of illegal activity. The need for additional forensic assessments of pet-trade iguanas is evident, especially given that their value is driven by variety and rarity, which is further intensified by recent taxonomic changes.