Unusually for a lizard, the diurnal armadillo girdled lizard is a sociable reptile (2) (5), with between 1 and 30 individuals sharing a rock crevice for long periods. Normally these groups comprise an adult pair along with subadults and juveniles (6). When resting in a crack in a rock, the armadillo girdled lizard is well protected and its spiny scales make it virtually impossible for anything to remove it from its shelter (2). If out in the open, the armadillo rock lizard will retreat back to the rock at the first sign of danger (2), but it is a slow runner making it vulnerable to predation (7). However, this lizard does have another clever way of protecting itself. If caught by a predator or a human, it will curl up, grip its tail in its jaws and form a tight, armoured ball in the manner of an armadillo. In this position, the soft underparts are protected and the lizard is too spiky for many predators to eat (2), although this tactic does prove ineffective against birds of prey (5).
The armadillo girdled lizard feeds largely on insects, which are attracted to the abundant flowers of the region it inhabits (2). The most important prey is the southern harvester termite (Microhodotermes viator), but it is also known to feed on items such as millipedes, scorpions and plant material (8).
Mating in the armadillo girdled lizards takes place in spring (4), and each year females give birth to a single, large young at the end of April, at the end of the dry season before the winter rains commence in May (9) (10). These reptiles become sexually mature when they reach a snout-vent length of about 95 millimetres (9).