Agamidae

Agamidae View in CoL View at ENA ( Figs 49A, B View Figure 49 , 50A–D View Figure 50 , 51A View Figure 51 )

In Laudakia stellio , only the prearticular and the articular are fused together, whereas the angular and surangular remain free. The angular ( Fig. 49A, B View Figure 49 ) is slender and elongated, with a strong dorsolateral concavity and pointed anterior and posterior ends. It is straight, but bends slightly in dorsal direction posteriorly. A small foramen is visible in ventral view, at midlength; it continues in a shallow groove on the medial concave surface of the bone, but does not open dorsally. The lateral surface of the angular is smooth, except for a sharp and sigmoid-shaped ridge running along its entire length. The surangular of Laudakia stellio ( Fig. 50A, B View Figure 50 ) is dorsoventrally enlarged and straight in dorsal view. It is moderately thin in its anterior-half, but gets thicker in the posterior one. In medial view, it has a pointed posterior end and a truncated anterior one, provided with two anteriorly directed and pointed projections (a very short ventral one and a longer dorsal one). On the medial surface, two very low ridges run in the posterior direction from these two projections ( Fig. 50A View Figure 50 ). The dorsal ridge is less developed than the other and marks the ventral margin of the anterior expanded area, whereas the more developed ventral ridge touches the prearticular/ articular complex and marks the dorsal margin of the articulation surface with the angular. The anterior expanded area is less developed than in other lizards and a sharp ridge marks its dorsal margin. The posterior expanded area is short and very poorly arched, but it is moderately thick. The posterior-half of the lateral surface of the bone is smooth, whereas the anterior one is covered by the deep articulation surface with the posterior end of the dentary ( Fig. 50B View Figure 50 ). The imprints of the posterior processes of the latter bone are recognizable by the posterior portion on this articulation surface. Both the anterior and the posterior surangular foramina are shifted towards the middle of the height of the bone. The anterior end of the prearticular/articular complex ( Fig. 50C, D View Figure 50 ) is truncated and the expansion contacting the surangular is reduced. At this expansion, a rounded tubercle is present on the medial surface of the bone ( Fig. 50C View Figure 50 ). The articular condyle is subquadrangular in dorsal view and roughly flat ( Fig. 51A View Figure 51 ). The retroarticular process is long, robust and slightly dorsally curved in the posterior portion. Its dorsomedial concavity is deep and bordered dorsally and ventrally by sharp ridges (of which the ventral one is the well-developed tympanic ridge) and its posterior end is rod-like and truncated. The lateral surface of the process is smooth, but a distinct and sharp ridge-like expansion runs along the ventral margin. A thick, well-developed and thumb-like angular process is present, developing in the anteroventral direction. The lateral surface of the complex is smooth, except for a low ridge marking the ventral margin of the articulation surface with the angular. The adductor fossa is anteroposteriorly elongated and a sharp ridge connects its medioventral margin to the ventral corner of the articular condyle.