Nostimochelone lampra gen. et sp. nov., an enigmatic new podocnemidoidean turtle from the Lower Miocene of northern Greece

A new podocnemidoidean turtle, Nostimochelone lampra gen. et sp. nov., was recently recovered from littoral marine-estuarine sediments of the lower Miocene Zeugostasion Formation, near the village of Nostimo in northwestern Macedonia, Greece. This new taxon is characterized by a mosaic of primitive and derived features most notably the presence of a broad embayment on the anterior carapace margin, which involves both the nuchal (whose width > length) and first pair of peripherals, a continuous series of six markedly elongate and very narrowed hexagonal neural bones, extension of the axillary buttress onto the midline of the anteroposteriorly elongate costal I (leaving a concave scar) and also laterally across the peripheral II–peripheral III suture, medial contact of the humeral scutes (implying a small intergular), and extensive overlap of the pectoral scutes on the entoplastron, probably extending to the epiplastral–hyoplastral suture. Conclusive phylogenetic placement of Nostimochelone is difficult to establish because the remains are incompletely preserved. Nevertheless, its discovery is significant because it represents both the first record of a pleurodiran turtle from Greece and also one of only a handful of fossil podocnemidoidean occurrences thus far documented from the Neogene of Europe.