Cryptic variation in the Moroccan high altitude lizard Atlantolacerta andreanskyi (Squamata: Lacertidae)

Abstract

Atlantolacerta andreanskyi is a mountain specialist lacertid lizard, restricted to areas above 2400 m of the High Atlas Mountains of Morocco, with apparently no geographic connection between different populations. In a recent molecular study, populations from A. andreanskyi collected across its distribution area were analysed, showing unprecedented levels of genetic differentiation for mitochondrial markers, which were also partially differentiated for nuclear markers. Here we aim to investigate, for the first time, the phenotypic variability of this species, using univariate and multivariate analyses on linear measurements, pholidotic and coloration characters in six populations of A. andreanskyi previously analysed genetically and covering most of its distribution range. The results show that despite the high genetic divergence previously detected, morphological variation among populations was low. Thus, although some genetic lineages could be partially discriminated morphologically at a multivariate level, single diagnostic traits could not be identified, and thus, they can be considered as cryptic lineages. Although the extreme genetic diversity observed supports the existence of six independent entities, more prospecting and analysis of additional populations will be needed to confirm the evolutionary independence of the lineages before their formal description.