Scincidae

Scincidae View in CoL ( Figs 27G–P View Figure 27 , 28E–N View Figure 28 )

The palatine process of the pterygoid of European scincids is a laminar structure provided with a thicker area in the middle rather than a robust medial margin. It is long and subtriangular in Ab. kitaibelii ( Fig. 27G, H View Figure 27 ), long and subrectangular in Chalcides chalcides , Chalcides striatus and Tr. aurata ( Fig. 27I, J, O, P View Figure 27 ), and short and subtriangular in Chalcides ocellatus and Ophiomorus punctatissimus ( Fig. 27K–N View Figure 27 ). The medial margin of the process can be straight ( Tr. aurata ; Fig. 27O, P View Figure 27 ), slightly convex ( Ab. kitaibelii , Chalcides chalcides , Chalcides striatus and Ophiomorus punctatissimus ; Fig. 27G–J, M, N View Figure 27 ) or strongly convex ( Chalcides ocellatus ; Fig. 27K, L View Figure 27 ). This morphology fits with the ‘alpha’- type scincid pterygoid described by Greer & Parker (1968) and Greer (1974) (see also: Evans, 2008). In Chalcides , the anterior end of the process is bifurcate: it has either a V-shaped (most specimens of Chalcides chalcides ; Fig. 27I, J View Figure 27 ) or U-shaped ( Chalcides ocellatus , Chalcides striatus and Chalcides chalcides MDHC 398; Fig. 27K, L View Figure 27 ) notch in the middle, flanked by two small and pointed processes. The palatine process of Tr. aurata has a straight but slightly interdigitated anterior margin, and a long and slender anterior projection by the medial corner ( Fig. 27O, P View Figure 27 ). Ablepharus kitaibelii has an anteriorly pointed palatine process ( Fig. 27G, H View Figure 27 ), whereas that of Ophiomorus punctatissimus has a wavy anterior margin ( Fig. 27M, N View Figure 27 ). Pterygoid teeth are absent in Ab. kitaibelii and Chalcides ( Fig. 27H, J, L View Figure 27 ), but present in very low numbers (just one or two in Tr. aurata MDHC 280 and three in all specimens of Ophiomorus punctatissimus ) in Tr. aurata and Ophiomorus punctatissimus ( Fig. 27N, P View Figure 27 ). The moderately wide pterygoid recess is very deep and roughly V- or U-shaped in Chalcides chalcides ( Fig. 27I, J View Figure 27 ), shallow and U-shaped in Chalcides ocellatus and Ophiomorus punctatissimus ( Fig. 27K–N View Figure 27 ), and deep and U-shaped in Ab. kitaibelii , Chalcides striatus and Tr. aurata ( Fig. 27G, H, O, P View Figure 27 ). As for the ridges of the pterygoid flange, the dorsal one is moderately developed, whereas the ventral one is well developed. The development of the ridges decreases in the small species Ab. kitaibelii ( Fig. 27G, H View Figure 27 ), but their proportions are the same. In Ophiomorus punctatissimus , both the dorsal and the ventral ridges are well developed ( Fig. 27M, N View Figure 27 ). The quadrate process is long and straight; its posterior end is narrow in dorsal view and finger-shaped in lateral view. The fossa columellae is slightly anteroposteriorly elongated. In Chalcides bedriagai , Chalcides chalcides , Chalcides striatus and Tr. aurata , the fossa is followed by a pterygoid ridge that is sharp in its anterior portion, whereas posteriorly it tends to lower and to shift in a ventral direction towards the lateral surface ( Figs 27I, O View Figure 27 , 28G, M View Figure 28 ). The ridge is completely absent in Chalcides ocellatus and Ophiomorus punctatissimus ( Figs 27K, M View Figure 27 , 28I, K View Figure 28 ), whereas only a hint near the fossa is present in Ab. kitaibelii ( Figs 27G View Figure 27 , 28E View Figure 28 ). The basipterygoid fossa is a flattened surface, but the wide surface for the insertion of the pterygoideus muscle is strongly concave. With the exception of Ab. kitaibelii and Chalcides striatus MNCN 16508, a foramen opens in the ventral direction on the ventral portion of the lateral surface of the bone, at the joint of the three branches. Measurements of the maximum length are given in the Supporting Information 4.