Abstract
The ecological and biogeographic limits of arid-adapted reptiles in the Eastern Mediterranean remain poorly understood. Here, we document the first confirmed occurrence and genetic affiliation of the desert racer, Psammophis schokari (Forskål, 1775), in Lebanon, representing the northern limit of its confirmed distribution in the western Levant, where its presence has long remained uncertain. Seventeen records from 11 localities (17-1,148 m a.s.l.) reveal that the species occupies a wide ecological gradient encompassing lowland agricultural areas, semi-arid foothills, and even seasonally snow-covered sites. Mitochondrial cytochrome b sequences place the Lebanese populations within the widespread "Middle Eastern lineage", yet their haplotypes show a closer affinity to those from North Africa than to currently sampled populations from the southern Levant. This pattern is consistent with historical Afro-Levantine connectivity and suggests that Lebanon may have been reached during one or more Pleistocene dispersal/colonization episodes from northern Africa. The frequent occurrence of individuals in non-desert habitats and even during winter months demonstrates a high degree of ecological flexibility and tolerance to cooler Mediterranean conditions. Our results thus highlight the ability of P. schokari to persist and expand beyond typical desert environments and thereby shedding light on the northern biogeographic limits of arid-adapted snakes in the Middle East. This study fills a significant distributional gap for the genus Psammophis in the Levant and underscores the need for broader sampling to clarify the species' past colonization routes and evolutionary history across the region.