armadillo lizard, (species Cordylus cataphractus), a southern African member of the family Cordylidae, known for its defensive body posture. This lizard is about 25 cm (10 inches) long. When danger threatens, it forms a ball by rolling on its back and taking its tail in its mouth. Protected by hard, bony scales and spines on the head and tail, the armadillo lizard remains in this position until the danger disappears.