Physical characteristics

Girdled lizards are the most typical cordylines, with well-developed limbs and stout bodies covered with overlapping, spiny scales. The bodies of flat lizards, however, are covered with small, granular scales, although the legs may still have a few scattered, spiny scales. Scales on the belly and back are strengthened with bony elements (osteoderms). A longitudinal, expandable fold of granular scales runs along the flanks

A common grass lizard (Chamaesaura anguina) eating a grasshopper and showing elongate form, Port Elizabeth, South Africa. (Photo by Bill Branch. Reproduced by permission.)

to give flexibility (it is reduced in size in some genera). The head is usually triangular with large, symmetrical, bony head shields. The tongue has a simple notch and is covered in papillae. Femoral pores are conspicuous in males, and sometimes also in females. The tail can be shed and regenerated. In girdled lizards it is ringed with spiny scales and is not much longer than the head-body length. Plated lizards have much longer tails, ringed with elongate, rectangular scales.

Among cordylines, flat lizards are unmistakable. The body is very flat and covered with granular scales, while the legs often have scattered spiny scales. These depressed dandies are clothed in Jacobean splendor, the colors varying from species to species. They are most vivid on the belly, where their intensity is hidden from predators. Females and juveniles have black backs, usually attractively marked with three pale, longitudinal, dorsal stripes. Males grow slightly larger than females.

Even though they are not closely related, grass and snake lizards have evolved elongate bodies and long tails that allow them to move freely in long grass. They move with the speed and agility of snakes. The vestigial limbs are often reduced to minute spikes, and although they appear useless they give stability when the lizard is at rest. Their rustic colors camouflage them in dried grass.

Plated lizards (Gerrhosaurus) have stout bodies and well-developed limbs. The desert plated lizard (G. skoogi) is adapted for desert life. The spadelike snout, relatively short, conical tail, and cylindrical body allow it to dive into the loose sand of slip faces, while the long limbs and fringed toes allow it to run at lightning speed across wind-compacted sand. The dwarf plated lizard (Cordylosaurus subtessellatus) is a very small (to 6 in [15 cm]), brightly colored species restricted to the arid western regions of southern Africa. Plated snake lizards or seps (Tetradactylus, six species) show a progressive evolutionary transition from normal-limbed species to others that have become snakelike with vestigial limbs. Madagascan plated lizards (Tracheloptychus, two species, and Zonosaurus, 13 species) are more gracile and skinklike than their African cousins and have reduced body armor.

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