The highly flattened members of Platysaurus are swift, lightly-armored rock specialists. Their extreme flat morphology allows them to occupy the narrowest of cracks and they are often found under exfoliated flakes of granite, gneiss and sandstone. They are sociable animals, forming dense colonies, with males maintaining territories during the breeding season. Platysaurus display extreme sexual dichromatism; the males are spectacularly colored, while females and juveniles are drab by comparison. During territorial disputes, males expose their brightly colored bellies by tilting sideways, or raise the head and fore-body on straightened forelimbs, revealing the bright coloration of the throat and chest. The dorsal surface is covered with granular scales, and osteoderms are restricted to the large scales on the head, legs and the lightly armored tail.

Platysaurus are the only oviparous members of the Cordylidae. They nest communally in deep cracks, producing one or two large, elongated, soft-shelled eggs each year. Due to their adaptation to a rupicolous lifestyle they are limited to specific habitats and are thought to be poor dispersers. The genus has a disjunct distribution, with 24 Platysaurus taxa occurring in the Mpumalanga, Limpopo and KwaZulu Natal provinces of South Africa, Swaziland, Zimbabwe, Malawi, Tanzania and Mozambique and two species occupying a much smaller range along the border of South Africa and Namibia. It is hypothesized that the Southwestern forms are a relict population that was separated from the Northeastern species by the spread of the Kalahari Desert (Broadley, 1978, Jacobsen, 1994), or by the changing course of the Orange River (Scott et al., 2004). An upcoming phylogenetic study that has comprehensive taxon sampling will revise the taxonomy further, naming several new species (Whiting and Keough in prep).