Scincus oficinalis Laur and Chalcides ocellatus Forskal were chosen as representatives of oviparous and viviparous lizards, respectively. Both lizards excrete their urinary constituents in the form of dry, hard concretions. The material employed in the present work was collected, during the summer, from twenty healthy lizards of each species. The procedure followed in the present investigation ...

We integrate biological experiment, empirical theory, numerical simulation and a physical model to reveal principles of undulatory locomotion in granular media. High-speed X-ray imaging of the sandfish lizard, Scincus scincus, in 3 mm glass particles shows that it swims within the medium without using its limbs by propagating a single-period travelling sinusoidal wave down its body, resulting i...

Phylogenetic analysis using up to 1325 base pairs of mitochondrial DNA from 179 specimens and 30 species of Chalcides, Sphenops, Eumeces, Scincopus and Scincus indicates that Sphenops arose twice independently within Chalcides. It is consequently synonymized with that genus. Chalcides in this broader sense originated in Morocco, diversifying into four main clades about 10 Ma, after which some o...