Ctenophorus

Central netted dragon Ctenophorus nuchalis, copyright kazza21.

Belongs within: Agamidae.

Dragons in a desolate land
Published 31 March 2014

The comb-bearing dragons of the genus Ctenophorus are an assemblage of 28 (and counting!) species of medium-sized lizards found around Australia. Darren Naish has recently been giving an overview of the Australian dragons; you can read what he’s already said about Ctenophorus here. I’d suggest reading that first, then coming back here.

Ring-tailed dragon Ctenophorus caudicinctus, from here.

Species of Ctenophorus are distinguished from other dragons by the presence of a row of tectiform (roof-shaped) scales running from behind the nostrils under the eyes, though in some species this row is only weakly pronounced (Melville et al. 2008). In most species, the tympanum (ear-drum) is exposed, though a few species have it covered over. I’m personally familiar with one species of Ctenophorus, the ring-tailed dragon C. caudicinctus. Where we’ve been doing fieldwork on Barrow Island, ring-tailed dragons are a common site perched on termite mounds or larger rocks, invariably just one dragon to a rock, monitoring the surrounding territory for food or mates. Not all Ctenophorus species engage in such behaviour: the species have been divided between three groups depending on whether they prefer rocky habitats, whether they prefer sandy habitats and use tufts of spinifex and other vegetation for cover, or whether they shelter in burrows. Phylogenetic analysis suggests that the burrowing habit was ancestral for the genus; rock-dwelling or scrub-dwelling habits may have each evolved more than once within Ctenophorus, though the possibility cannot be entirely ruled out that they may characterise monophyletic groups (Melville et al. 2001). These differences in ecology also correlate with morphological differences: rock-dwelling species have dorsoventrally flattened heads, while the scrub-dwelling species are long-legged and cursorial.

Military dragon Ctenophorus isolepis, a sand-dwelling species associated with spinifex, photographed by Stewart Macdonald.

While some species of Ctenophorus are widespread, others are far more restricted in range. Ctenophorus caudicinctus, for instance, is found across most of northern Western Australia and the Northern Territory, but Butler’s dragon* C. butleri is restricted to coastal sand dunes between Shark Bay and Kalbarri in Western Australia (Cogger 2014). The most recently described species to date, the Barrier Range dragon C. mirrityana, is known from two locations about 100 km apart in western New South Wales (McLean et al. 2013). And it possibly does say something that new species continue to be described even in this not inconspicuous genus.

*Or should that be ‘Butlers’ dragon’, as it was apparently named after both Harry and Margaret Butler?

Lake Eyre dragon Ctenophorus maculosus, photographed by Rune Midtgaard.

Perhaps the most hard-core of the comb-bearing dragons is the Lake Eyre dragon Ctenophorus maculosus, a specialised inhabitant of dry salt lakes in South Australia. This is a spectacularly harsh environment: searing hot sun, often at temperatures above 40°, beating down on a crust of crystallised salt. Few other animals can survive there without spontaneously combusting. The dragons protect themselves from the head by burrowing into the layer of unconsolidated sand beneath the salt-crust; Pedler & Neilly (2010) discovered one female with its head protruding from a burrow with an entrance too small for its body, and suggested that she must have gotten there by ‘swimming’ through the sand. The Lake Eyre dragons feed on ants such as Melophorus (themselves no slouch in the hard-core stakes) or other insects that have become stranded on the salt-pan. When the lake becomes filled with water (as it does about once a decade or so), the dragons are forced to flee into the habitats surrounding the lake shores and wait for the flood to clear. Two Western Australian species, the claypan dragon Ctenophorus salinarum and the Lake Disappointment dragon C. nguyarna, are also associated with salt-pans, but they do not have quite the level of specialisation of the Lake Eyre dragon.

Systematics of Ctenophorus
<==Ctenophorus Fitzinger 1843C18
    |--C. adelaidensis (Gray 1841)C18
    |--C. butlerorum (Storr 1977)E19 [=Amphibolurus parviceps butleriE19, C. butleriC18]
    |--C. caudicinctus (Günther 1875)C18 [incl. Amphibolurus caudicinctus mensarumE19, C. caudicinctus mensarumC18]
    |    |--C. c. caudicinctusC18
    |    `--C. c. macropusC18
    |--C. chapmani (Storr 1977) [=Amphibolurus adelaidensis chapmani]E19
    |--C. clayi (Storr 1966) [=Amphibolurus clayi]E19
    |--C. cristatus (Gray 1841)C18
    |--C. decresii (Duméril & Bibron 1837)C18
    |--C. femoralis (Storr 1965) [=Amphibolurus femoralis]E19
    |--C. fionni (Procter 1923)C18
    |--C. fordi (Storr 1965) [=Amphibolurus fordi]E19
    |--C. gibba (Houston 1974)C18
    |--C. graafi (Storr 1967)E19 [=Amphibolurus caudicinctus graafiE19, C. caudicinctus graafiC18]
    |--C. inermisSH90
    |--C. infans (Storr 1967)E19 [=Amphibolurus caudicinctus infansE19, C. caudicinctus infansC18]
    |--C. isolepis (Fischer 1881)C18
    |    |--C. i. isolepisBMS09
    |    |--C. i. citrinus (Storr 1965) [=Amphibolurus isolepis citrinus]E19
    |    `--C. i. gularisBMS09
    |--C. maculatus (Gray 1831)C18
    |    |--C. m. maculatusE19
    |    |--C. m. badius (Storr 1965) [=Amphibolurus maculatus badius]E19
    |    |--C. m. dualis (Storr 1965) [=Amphibolurus maculatus dualis]E19
    |    `--C. m. griseus (Storr 1965) [=Amphibolurus maculatus griseus]E19
    |--C. maculosus (Mitchell 1948)C18
    |--C. mckenziei (Storr 1981) [=Amphibolurus mckenziei]E19
    |--C. mirrityana McLean, Moussalli et al. 2013C18
    |--C. nguyarna Doughty, Maryan et al. 2007C18
    |--C. nuchalis (De Vis 1884)C18
    |--C. ornatus (Gray 1845)C18
    |--C. parviceps (Storr 1964) [=Tympanocryptis parviceps]E19
    |--C. pictus (Peters 1866)C18
    |--C. reticulatus (Gray 1845)ADD08 [incl. Amphibolurus darlingtoni Loveridge 1932E19]
    |--C. rubens (Storr 1965) [=Amphibolurus isolepis rubens]E19
    |--C. rufescens (Stirling & Zietz 1893)C18
    |--C. salinarum (Storr 1966) [=Amphibolurus pictus salinarum]E19
    |--C. scutulatus (Stirling & Zietz 1893)C18
    |--C. slateri (Storr 1967)E19 [=Amphibolurus caudicinctus slateriE19, C. caudicinctus slateriC18]
    |--C. tjantjalka Johnston 1992C18
    |--C. vadnappa (Houston 1974)C18
    `--C. yinnietharra (Storr 1981) [=Amphibolurus yinnietharra]E19

*Type species of generic name indicated

References

[ADD08] Aplin, K., S. Donnellan & J. Dell. 2008. The herpetofauna of Faure Island, Shark Bay, Western Australia. Records of the Western Australian Museum Supplement 75: 39–53.

[BMS09] Bell, C. J., J. I. Mead & S. L. Swift. 2009. Cranial osteology of Moloch horridus (Reptilia: Squamata: Agamidae). Records of the Western Australian Museum 25 (2): 201–237.

Cogger, H. G. 2014. Reptiles and Amphibians of Australia 7th ed. CSIRO Publishing: Collingwood.

[C18] Cogger, H. G. 2018. Reptiles and Amphibians of Australia updated 7th ed. CSIRO Publishing: Collingwood.

[E19] Ellis, R. J. 2019. An annotated type catalogue of the dragon lizards (Reptilia: Squamata: Agamidae) in the collection of the Western Australian Museum. Records of the Western Australian Museum 34 (2): 115–132.

McLean, C. A., A. Moussalli, S. Sass & D. Stuart-Fox. 2013. Taxonomic assessment of the Ctenophorus decresii complex (Reptilia: Agamidae) reveals a new species of dragon lizard from western New South Wales. Records of the Australian Museum 65 (3): 51–63.

Melville, J., L. P. Shoo & P. Doughty. 2008. Phylogenetic relationships of the heath dragons (Rankinia adelaidensis and R. parviceps) from the south-western Australian biodiversity hotspot. Australian Journal of Zoology 56: 159–171.

Melville, J., J. A. Shulte II & A. Larson. 2001. A molecular phylogenetic study of ecological diversification in the Australian lizard genus Ctenophorus. Journal of Experimental Zoology 291: 339–353.

Pedler, R. & H. Neilly. 2010. A re-evaluation of the distribution and status of the Lake Eyre dragon (Ctenophorus maculosus): an endemic South Australian salt lake specialist. South Australian Naturalist 84 (1): 15–29.

[SH90] Storr, G. M., & G. Harold. 1990. Amphibians and reptiles of the Shark Bay area, Western Australia. In: Berry, P. F., S. D. Bradshaw & B. R. Wilson (eds) Research in Shark Bay: Report of the France-Australe Bicentenary Expedition Committee pp. 279–285. Western Australian Museum.

Leave a comment

Your email address will not be published. Required fields are marked *