Size The species is highly dimorphic in body size with females reaching a maximum snout-vent length of approximately 150 mm and males only 115 mm. The maximum total length of females (i.e., including the tail) can be well over 500 mm.
Description The Cape Grass Lizard is a snakelike lizard with an elongated body and long tail. The tail is 3-4 times longer than the body. The body scales are keeled and arranged in 26-30 longitudinal rows. The limbs are highly reduced with the hind ones having one clawed digit and the front ones two. Each hind limb may have one to two femoral pores. Individuals may be uniformly coloured in olive to grey above or may have vertebral and dorsolateral black stripes. The belly may be whitish to golden yellow in colour.
Biology The Cape Grass Lizard is an arboreal lizard that lives in grass and restio habitats along the Cape Fold Mountains and coastal lowlands. Like other cordylids, it is a sit-and-wait forager. It uses its long elongated body to distribute its weight on top of the grass or restios where it waits for its food, mainly grasshoppers, to come close. It then uses its long body, like a chameleon uses its tongue, to catch insects over the gaps between plants. During periods of inactivity it shelters in a curled up position at the base of the grass or restio tufts. Unlike other lizards which shelter from fire by hiding underground, underneath rocks, or in crevices, grass lizards flee from fire by so-called grass-swimming, a form of lateral undulating movement. Although some individuals may survive in refugia, the species is usually heavily impacted on by fire. Recolonisation of burnt areas can happen quickly because fecundity in this live-bearing lizard is much higher than in other cordylids. Up to 17 young can be born at a time, in comparison to clutch sizes of 1-5 in other cordylids. Clutch size is correlated to body size of females. Reproduction is also atypical for a cordylid in that it is aseasonal. Females can give birth at any time of the year and not only in late summer and autumn as in other cordylids. Males have a postnuptial cycle, in other words spermatogenesis peaks during autumn and not during spring as in most other cordylids.
Distribution Occurs from Citrusdal in the Western Cape southwards and eastwards along the Cape Fold Mountains and coastal lowlands to the Eastern Cape and coastal lowlands of Kwazulu Natal and along the escarpment to the Mpumalanga Drakensberg.
Distribution in the GCBC Probably only occurs in the extreme southern part of the Biodiversity Corridor, from between Citrusdal and Op-den-Berg, southwards along the Cape Fold Mountains.
Conservation status Not listed in the latest South African Red Data Book for reptiles and amphibians, or in the IUCN Red List of Threatened Species. Like all other cordylid species, it is listed internationally in Appendix II of the Convention on the International Trade in Endangered Species of Fauna and Flora (CITES); legislation which regulates the international trade in these animals.
Threats Local populations are threatened by poor fire management.
Current studies Honour student, Lizanda du Preez. PhD-student, Jenny Jackson, of the Department of Zoology, Stellenbosch University is studying the fire ecology of this species.
Other recent studies include:
DU TOIT, A., MOUTON, P.LE F.N., GEERTSEMA, H. & FLEMMING, A.F. 2002. Foraging mode of serpentiform, grass-living lizards: a case study of Cordylus anguinus. African Zoology 37: 141-149.
DU TOIT, A., MOUTON, P.LE F.N., & FLEMMING, A.F. 2003. Aseasonal reproduction and high fecundity in the Cape Grass Lizard, Cordylus anguinus, in a fire-prone habitat. Amphibia-Reptilia 24: 471-482.