Anguidae

Anguidae View in CoL View at ENA ( Fig. 22V View Figure 22 –AA)

The quadrate of European anguids is a straight and subrectangular bone in anterior view. Only a low to moderately developed lamina is present along the lateral margin of the pillar. The degree of development of this lamina is higher in Pseudopus apodus ( Fig. 22Y, Z View Figure 22 ) than in Anguis gr. An. fragilis ( Fig. 22V, W View Figure 22 ). Because of this, Anguis gr. An. fragilis lacks a real conch ( Fig. 22W View Figure 22 ), whereas the conch of Pseudopus apodus is narrow and very shallow ( Fig. 22Z View Figure 22 ). A similar-sized or slightly more developed lamina is present on the medial side of the bone, developing a small pterygoid flange near its ventral end (less recognizable in Pseudopus apodus and in juveniles of Anguis gr. An. fragilis ). The cephalic condyle is very strongly expanded both posteriorly and anteriorly and so the bone appears very wide in its dorsal portion in lateral view. In Anguis gr. An. fragilis , the anterior expansion tends to bend ventrally, creating an anterodorsally directed articulation surface with a rounded outline in lateral view ( Fig. 22X View Figure 22 ). In Pseudopus apodus , the same expansion does not bend ventrally and the anterior outline of the bone appears angular in lateral view ( Fig. 22 View Figure 22 AA). The posterior expansion is straighter in lateral view and slightly wider in dorsal view. A ridge runs ventrally from the expansion along the posterior surface of the pillar body of the bone. The mandibular condyle is moderately wide in posterior view and its portions are poorly ventrally developed and similar in size. Even if the lateral lamina is not much developed, a small ( Anguis gr. An. fragilis ) or deep ( Pseudopus apodus ) notch on the lateral side of the cephalic condyle is still recognizable in dorsal view: this could be a remnant of the foramen for the chorda tympani nerve. The maximum length varies from 1.9 mm to 2.7 mm in Anguis gr. An. fragilis and from 6.5 mm to 7.8 mm in Pseudopus apodus .

EPIPTERYGOID

The epipterygoid ( Fig. 23 View Figure 23 ) is a rod-like paired bone.