They defend themselves with osteoderms (flat bony plates in the skin) and by quickly retreating into rock crevices or burrows.

Some species of Cordylus have limited ranges and may be threatened with habitat destruction or over collecting for the pet trade.

Broadley (2006) recognized 47 species in the genus Cordylus, including eight species originally placed in the genus Pseudocordylus (P. fasciatus, P. langi, P. melanotus, P. microlepidotus, P. nebulosus, P. spinosus, P. subviridis, and P. transvaalensis) and Hemicordylus capensis.

Other members of the Cordylidae are the genera Chamaesaura (a group of legless lizards from southern and eastern Africa) and Platysaurus.

In 2011, a study based on the molecular phylogeny of the family suggested several species traditionally included in Cordylus should be moved to other genera: Hemicordylus (for capensis and nebulosus), Karusasaurus (for jordani and polyzonus), Namazonurus (for campbelli, lawrenci, namaquensis, peersi and pustulatus), Ninurta (for coeruleopunctatus), Ouroborus (for cataphractus) and Smaug (for breyeri, giganteus, mossambicus, regius, vandami and warreni).