A Monograph on the Osteology of Mesopotamian Spiny-tailed Lizards, Saara loricata (Blanford, 1874) (Sauria: Agamidae: Uromastycinae)

The species of the subfamily Uromastycinae are herbivorous burrowing lizards distributed from the African Sahara Desert to the Asian Thar Desert and across the Arabian Peninsula. Although osteological studies on Uromastycinae have a long history, a detailed description of the complete skeleton is lacking. We investigate the cranial and postcranial osteology of the Mesopotamian Spiny-tailed Lizard (Saara loricata, previously referred to Uromastyx). We studied articulated and disarticulated materials from five specimens and present a complete description of the bones of the species. Our study adds to the growing body of literature on the skeleton of agamid lizards. Unlike Uromastyx sensu stricto, in S. loricata no anterior premaxillary foramina exists on the anterior surface of the premaxilla, no contact exists between the frontal and the maxilla or premaxilla, the anterolateral processes of the frontal are unexposed in dorsal view so that the prefrontal and nasal are attached, and the pterygoid does not contact the vomer anteriorly and the quadrate posteriorly. Unlike its congener S. hardwickii, in S. loricata no anterior premaxillary foramen exists on the anterior surface of the premaxilla, a smaller ethmoidal foramen perforates the nasal, a well-developed, posteriorly extended socket-like notch is formed through anterior bifurcation of the jugal, an L-shaped suture line forms between the jugal and postorbital in dorsal view, and an interlocking suture between the surangular and dentary exists in S. loricata.