Is there only one species of flowerpot snake around the world? Phylogenetic position of a specimen from Italy (Ischia) (Serpentes: Typhlopidae)

The flowerpot blindsnake (Indotyphlops braminus), native to India, nowadays holds the widest global distribution among the snakes, due to passive transport by humans. Previous genetic analysis showed that two geographically separated mtDNA clades occur in India, one confined to the wetter parts of Western Ghats (“wet zone” clade), while the other distributed in the drier parts of central and eastern peninsular India (“dry zone” clade). All the so far studied flowerpot specimens found all over the world belong to the “wet zone” clade and are characterized by a very low mtDNA diversity. In this paper, the phylogenetic position, based on two mtDNA markers (16S and cytb) was assessed for one specimen of flowerpot blindsnake found in Ischia Island (Italy), one of the two localities where the species has been introduced in the country. The results showed an elevated divergence between the Ischia specimen and all other specimens from different worldwide non-native location (7.9% for 16S and 14.1 % for cytb). Moreover, the specimen unequivocally clusters within the Indian "dry zone" clade. In literature it has been suggested that the “dry zone” clade represents the nominal I. braminus, while the other clade represents a different and yet unnamed species. In this perspective, our results indicate that the Ischia specimen would be the first true I. braminus found outside its range of origin. Finally, the results of this study reinforce the necessity to continue studying the flowerpot snake populations outside their range of origin also from a chromosomal and morphological point of view.