Early Pliocene Varanus (Squamata, Varanidae) remains from Megalo Emvolon, Thessaloniki, Greece

This study describes new fossil varanid material from a recently discovered fossil spot (MVL site) at the Megalo Emvolon locality near Thessaloniki, Northern Greece, dated to 4.2-3.2 Ma (Early Pliocene, late Ruscinian, MN 15). The fossils, likely representing a single individual, are referred to Varanus cf. marathonensis based on cranial features, particularly the parietal, frontal, postorbitofrontal, dentary, and teeth. A key diagnostic trait is the wide angle between the squamosal and parietal processes of the postorbitofrontal, distinguishing it from Varanus mokrensis from the Early Miocene of Central Europe. Comparative analysis shows closer morphological resemblance with extant Australasian taxa, especially Varanus flavescens, rather than African ones, suggesting an origin from an Asian lineage. If indeed conspecific with Varanus marathonensis, the occurrence of Megalo Emvolon could represent the latest confirmed record of the species in Europe highlighting its resilience and extending its known temporal range. Additionally, the fossils provide palaeoclimatic evidence, indicating a warm and humid environment during the Early Pliocene in northern Greece. Trends of size reduction in the Plio-Pleistocene Greek Varanus likely correlate with climatic changes following the end of the Miocene.