Scincidae

Scincidae View in CoL ( Figs 8V–Y View Figure 8 , 9A–D View Figure 9 )

European scincids differ from other European lizards in having paired premaxillae, both provided with a laminar and subquadrangular palatal process ( Figs 8Y View Figure 8 , 9C View Figure 9 ). In Chalcides chalcides MDHC 398 and Ophiomorus punctatissimus MDHC 427, the two paired premaxillae are joined together by their ventral margin, suggesting that a possible fusion may be present in old individuals. Together, the palatal processes compose a structure similar to the subtrapezoidal lamina seen in gekkotans ( Villa et al., 2018a). Except maybe for Chalcides bedriagai , an incisive process can be present: it can be either split into two halves by the separation of the paired premaxillae or developed as a single process. Teeth are morphologically similar to those of gekkotans ( Villa et al., 2018a), being pleurodont, cylindrical, slender and provided with a labial and a lingual cusp [morphotype F sensu Kosma (2004)]. However, the tooth crown is slightly curved posteriorly and has a light striation on the lingual surface in scincids. Teeth of Chalcides ocellatus differ from those of the other species, because they are robust and provided with a blunt and mediolaterally enlarged crown ( Fig. 9A, B View Figure 9 ). Each premaxilla bears half of the ascending nasal process, which is long, moderately narrow and pointed in its entirety. Larger species have a proportionally longer and more slender ascending nasal process. In Ophiomorus punctatissimus MCZ 38517, the process displays a light constriction at its base and, therefore, assumes an arrow-shaped appearance in anterior view. Since the process is split by its medial line, a septonasal crest is not recognizable. The external surface of the premaxillae is smooth, with no traces of dermal ornamentation ( Figs 8V View Figure 8 , 9A View Figure 9 ). Measurements and number of tooth positions are given in the Supporting Information 4.