Data from: Genetic and ecological data reveal species boundaries between viviparous and oviparous lizard lineages

Identification of cryptic species is an essential aim for conservation
biologists to avoid premature extinctions of ‘unrecognized’ species.
Integrating different types of data can undoubtedly aid in resolving the
issue of species delimitation. We studied here two lineages of the common
lizard Zootoca vivipara that display different reproductive mode (the
viviparous Z. v. vivipara and the oviparous Z. v. carniolica) and that
overlap their distributional ranges in the European Alps. With the purpose
of delimiting species’ boundaries, we analyzed their ecological, genetic
and natural history features. More than 300 samples were collected and
analyzed at cytochrome b and 11 microsatellites loci for investigating
genetic variation, population structure, individual relatedness and
evolutionary histories of the two lineages. Additionally, we compared
their ecological niches using eight ecological variables. Genetic data
showed contrasting patterns of genetic structure between the two lineages,
different demographic dynamics and no hybridization events. Also strong
ecological differences (such as temperature) emerged between the two
lineages, and niche overlap was limited. Taken together, these results
indicate that Z. v. vivipara and Z. v. carniolica should be recognized as
two separate species, and particular conservation consideration should be
given to the oviparous lineage that tends to live in areas threatened by
increasing impact of human activities. However, recent and rapid climate
warming might determine an increasing risk for the persistence of the
viviparous lineage, being adapted to cold environments.