Saint Patrick, what about legless lizards? Tracing the mitochondrial affiliation and possible origin of Anguis (Squamata: Anguidae) population in Ireland

Ireland is home to only one native lizards’ species, the viviparous lizard and one of the few areas of the world where there are no native snakes. However, since the end of the 19th century, there have been reports indicating the presence of legless lizards, Anguis fragilis Linnaeus, 1758 population whose origin is unknown. As this genus has been intensively studied genetically and taxonomically in the past decade, we have decided to investigate newly obtained mtDNA sequences (ND2 gene) to trace affiliation of the Anguis population in Ireland. We genetically examined 12 individuals from the Burren area (western Ireland) and compared them to available data. The Irish population was identified as belonging to A. fragilis, specifically to the most common haplotype of the Illyrian-Central European haplogroup. This genetic affiliation is shared by populations across a wide European region, including the western Balkans, Spain, France, western Hungary, Austria, Germany, Latvia, Poland, the Czech Republic, Russia, Sweden, Norway, and Great Britain. Our findings showed that the Irish population does not exhibit unique mitochondrial variability. This haplotype is present across the range of the species, including Great Britain, which is not in contrast with the earlier hypothesis that nearby populations from this area, along with human-mediated introductions, could be the source of Anguis populations in Ireland. This is thus potentially the first documented case of Anguis introduction out of the native range. However, further research, including broader sampling in Great Britain and genomics, is required to determine and trace its exact origin.