Anguidae

Anguidae View in CoL View at ENA ( Fig. 45O–R View Figure 45 )

In anguids, the splenial is composed of a slender and pointed anterior-half and a wide and laminar posterior-half. The anterior-half is mediolaterally developed, ventrally covering the Meckelian fossa of the dentary. The posterior end of the bone is irregular, with three processes: a wider and posteriorly truncated dorsal process and two longer, slender and pointed ventral ones. Only the small anterior mylohyoid foramen is clearly visible at midlength, whereas a wide notch located on the anterodorsal margin of the bone marks the ventral margin of the anterior inferior foramen, lying between the splenial and the dentary. This notch is usually shallow, but it can be deep in some large specimens of Pseudopus apodus , because of the presence of a slender and pointed process dorsally ( Fig. 45Q, R View Figure 45 ). The anterior mylohyoid foramen is located ventrally to the posterior margin of the notch of the anterior inferior foramen in Pseudopus apodus ( Fig. 45Q, R View Figure 45 ), whereas it is shifted posteriorly in Anguis gr. An. fragilis ( Fig. 45O, P View Figure 45 ). A medial crest [prearticular crest in Klembara et al. (2014)] runs along the entire length of the bone on its lateral surface, whereas only a hint of the dorsal crest is present on the anterodorsal margin, at the notch of the anterior inferior foramen. The medial surface is smooth.

CORONOID

The paired coronoid ( Fig. 47 View Figure 47 ) is composed of five processes. The dorsally developed and subtriangular coronoid process stands out in the middle of the bone. Adding to this process, there are the labial process anterolaterally, the anteromedial process anteromedially, the posterior process posteriorly and the posteromedial process posteromedially. The anteromedial process is always larger and longer than the labial process and both are pointed. The morphology of other processes varies among different groups.