Plated lizards is a term that is more or less synonymous with the lizards of the family Gerrhosauridae, particularly the Gerrhosaurus species themselves. Originally classified as a full family, the Gerrhosauridae were downgraded to a subfamily of the family Cordylidae, the so-called "girdled lizards" or "sungazers". Not all authorities agree with this demotion, however, and further research recently concluded that on the basis of the skulls the Gerrhosauridae were indeed sufficiently different to be placed at the family level. Both groups (Gerrhosauridae and Cordylidae) hail from dry savannah in the south and east of Africa, from Sudan downwards, and from Madagascar. Unlike sungazers, however, plated lizards are often seen in the pet trade. They make for the most part good pet lizards, but there is still no single popular book dedicated to them, unlike the more widely kept Leopard Geckos, Blue-Tongued Skinks and Bearded Dragons, for example.
What follows is a rough guide to the Gerrhosauridae subfamily, its genera and species, with a special emphasis on the Gerrhosaurus species. The data herein has been compiled from several sources, and also from a bit of personal experience with these marvellous lizards.
The Gerrhosauridae comprise the following genera:
As a rule members of the Gerrhosauridae are characterised by solid but not stocky bodies, short necks, pointed heads, short but powerful limbs, and strong tails. It should be noted, however, that in the genus Tetradactylus, the limbs have been reduced to almost vestigial status and the body is rather snake-like, an adaptation often seen in skink species. Apart from these traits, one of the distinguishing marks of the Gerrhosauridae is a longitudinal "fold" along the side of the body (seen also incidentally in the Gerrhonotus species, which resemble many of the Gerrhosaurus lizards): this fold allows expansion of the body after a heavy meal, although its size varies among the different species: in Tracheloptychus species, for example, the fold is restricted to the neck region (Rogner). Many of the Gerrhosauridae have keeled scales, beneath which osteoderms (bony plates) are often present, hence the common name "plated lizards". All are egg layers.
At present members of the Gerrhosaurus and Zonosaurus genera are still regularly seen in the pet trade. At the moment virtually all are wild-caught, and while this does not seem to be placing a strain on the indigenous populations of Gerrhosaurus at least, in the interests of conservation we ought to be making every effort to produce more captive offspring. This is especially so as some if not all of these lizards have low clutch sizes, and the political and environmental situation in their home territories can change for the worse. In particular the environmental situation in Madagascar (home to all the Zonosaurus and Tracheloptychus species) is causing concern due to deforestation and the rise of slash-and-burn agriculture.
The archetypal plated lizards - Gerrhosaurus
The Madagascar plated lizards - Zonosaurus
The lesser-known plated lizards - Angolosaurus, Cordylosaurus, Tetradactylus, Tracheloptychus
Thanks are especially due to Klaus Adolphs who kindly answered some taxonomic questions by E-mail and who proof-read these pages and made some important corrections, to Lucy Towbin who encouraged me in the research and writing of these pages, and to the rest of the members of the Sudan Plated Lizard mailing list (Sedg, Holly, Sharon, Jo Ann, Anna, Eric and Betty) who have freely exchanged information and experiences with one another, and to Leah Smith.
The only contemporary book devoted to Cordylidae and Gerrhosauridae lizards is Klaus Adolphs' Bibliography of the girdled lizards and plated lizards, Squamata Verlag, 1996, a copy of which I hope to obtain shortly. This is a bibliography of all the writings on the lizards with apparently over 1,000 useful quotations. Apart from this there is no single "popular" book (ie in the style of Barrons or TFH, who promised us one years ago but somehow never got round to it) dedicated to plated lizards, but several books offer sections on their care and the Internet has proven to be a useful source of taxonomic information.
A-Z of Lizard Care, Bartlett & Bartlett, Barrons, 1995. Good sections on Gerrhosaurus and Zonosaurus.
Keeping and Breeding Lizards, Mattison, Blandford 1996. A good chapter on the entire Cordylidae family that covers all the lizards, even those not normally seen in captivity.
Echsen [Lizards] Vol 2, Rogner, Ullmer Verlag, 1992. Usually a very good source of information, although it has been pointed out to me by one source that the section on needs to be treated with care, since this seems to have been a "theoretical" guess as to the captive requirements, whereas in reality this particular species is very hard to keep alive.
Field Guide to the Reptiles of South Africa, Bill Branch. Again very good as a general guide, but apparently contains some minor inaccuracies.
Jerry G Walls, "A Plated Lizard Primer", Reptile Hobbyist 4:3. This article contains some good photos, species descriptions and general information, but some of it seems hopelessly at odds with my own experience of Gerrhosaurus major. I would therefore suggest taking some of Jerry's care advice (and Jerry is a very knowledgeable writer) with a bit of caution.
Melissa Kaplan's caresheet
David Kirkpatrick's caresheet
Creatures Great and Small's caresheet
The German site Squamata Verlag has a very thorough and comprehensive listing of books and sources for data on both the Gerrhosaurinae and the Cordylinae (sungazers and kin). The site is in both German and English, side by side.