Genetic insights into the identity and distribution of Tarentola spp. geckos on Lampedusa island

Abstract

The Sicily Channel islands are known as biogeographic crossroads between European and African fauna. In this context, Lampedusa hosts a mainly Maghrebian herpetofauna, among which a Moorish gecko (sensu lato) belonging to a North African species-rank clade, provisionally named "Tarentola fascicularis/deserti" (sensu Rato et al., 2017). Here, we investigated the distribution of Tarentola spp. using the 16S mitochondrial DNA fragment on individuals from Lampedusa and verified the possible occurrence of T. mauritanica. This is a widely introduced species, hardly distinguishable based on morphological traits from T. fascicularis/deserti. Our molecular results support the hypothesis that both T. fascicularis/deserti and T. mauritanica occur in Lampedusa. Furthermore, nine out of eleven sequences are lumped together with T. fascicularis/deserti clade, suggesting the natural biogeographic connection between Tunisia and Lampedusa. Conversely, the detection of T. mauritanica haplotypes, exclusively within the Lampedusa port area, strongly point out a recent human-mediated introduction of the species. The finding of these two distinct mitochondrial lineages suggests the co-occurrence of African and European dispersion routes in the extant Lampedusa herpetofauna. In light of this, it is necessary to increase sampling efforts to other islands across Sicily Channel to better assess the origin and phylogenetic relationships of gecko populations.