Sand Dragons: Species of the Ctenophorus maculatus Complex (Squamata: Agamidae) of Australia's Southern and Western Interior
Knowledge of the extraordinary species richness of Australian desert lizards has expanded as new approaches integrating morphological and genetic data reveal unsuspected differentiation. The genus Ctenophorus is a major arid zone radiation and the most species-rich Australian agamid clade. The monophyletic C. maculatus complex, the sand dragons, occupy most sandy arid and semiarid habitats across southern Australia. Published molecular data on nominal C. maculatus complex species, C. fordi, C. femoralis, and C. maculatus, suggested undescribed species presence, supported by dorsal color pattern and male throat and chest patch variation. We provide additional morphological data from all candidate species, recognizing a total of 11 species. Four taxa are elevations of subspecies to species, and four taxa are newly described species. Ctenophorus maculatus complex species vary interspecifically in sexual size dimorphism and dichromatism, with a mating system of nonterritorial males, contrasting with some other territorial Ctenophorus species. The diversity and high local abundance of these lizards make them a potential model group for furthering understanding of interactions between natural selection and sexual selection leading to speciation.ABSTRACT
Distribution of lineages within the Ctenophorus maculatus species complex across southern Australian sandy arid and semiarid regions. Shown are the state boundaries and major water bodies. Scale and larger continental reference are inset. More detailed maps of contact points are found in Figure S2.
Plots of the first two linear discriminant axes (with % variance explained) from discriminant function analysis of all Ctenophorus species (males in A, females in B). The three morphological groups of species we name the inland sand dune (C. tjakalpa, C. kartiwarru, and C. femoralis), heath and coastal sand dune (C. maculatus, C. griseus, C dualis, and C. badius), and mallee (C. fordi, C. spinodomus, C. tuniluki, and C. ibiri) species. For males, inland sand dune species were excluded first (B), whereas for females it was the heath and coastal sand dune species (C). Secondarily excluded for males were the heath and coastal sand dune species (D), and for females it was the mallee species (E). This left the mallee species and inland sand dune species for males and females, respectively, in these last plots.
Dimensional differences (D1 vs. D2, with % variance explained) from multiple correspondence analyses of categorical data between all Ctenophorus species, for males (A) and females (B) analyzed separately.
Variation in male throat badges seen within Ctenophorus badius (A–C) relative to typical C. maculatus male throat badge (D): (A) Edel Land Peninsula; (B) Cape Cuvier Coast, west of Lake McLeod; (C) Cape Cuvier Coast, west of Lake McLeod; and (D) Denham, Peron Peninsula (photos: D. L. Edwards).
Live pictures of heathland and coastal sand dune species: Ctenophorus maculatus, C. badius, C dualis, and C. griseus: (A) C. maculatus, male, Eagle Bluff, Peron Peninsula, Western Australia (photo: B. Maryan); (B) C. maculatus, female, Monkey Mia, Peron Peninsula, Western Australia (photo: D. H. Fischer); (C) C. badius, male, Quobba homestead, Western Australia (photo: B. Maryan); (D) C. badius, female, Dirk Hartog Island, Western Australia (photo: R. Lloyd); (E) C. dualis, male, Eyre Bird Observatory, Western Australia (photo: M. Hutchinson); (F) C. dualis, female, Eyre Bird Observatory, Western Australia (photo: M. Hutchinson); (G) C. griseus, male, Lake Cronin, Western Australia (photo: B. Bush); and (H) C. griseus, female, Lake Cronin, Western Australia (photo: B. Bush).
Live pictures of inland sand dune species: Ctenophorus femoralis, C. kartiwarru, and C. tjakalpa. (A) C. femoralis male, 8 km N of Exmouth, Western Australia (photo: D. Robinson). (B) C. femoralis, female, Merlinleigh, Kennedy Range, Western Australia (photo: D. Robinson). (C) C. kartiwarru, male, Merna Mora, South Australia (photo: P. Tremul). (D) C. kartiwarru, female, Witchelina Reserve, South Australia (photo: B. Copland). (E) C. tjakalpa, male, Neale Junction, Western Australia (photo: S. Ford). (F) C. tjakalpa, female, north of Wirrulla, South Australia (photo: P. Tremul).
Live pictures of the mallee woodland species: C. fordi, C. spinodomus, C. ibiri, and C. tunluki. (A) C. fordi, male, 20 km E of Zanthus, Western Australia (photo: B. Maryan). (B) C. fordi, female, Goongarrie, Western Australia (photo: R. Lloyd). (C) C. spinodomus, male, Pooginook Conservation Park, South Australia (photo: I. Williams). (D) C. spinodomus, female, Gluepot Reserve, South Australia (photo: I. Williams). (E) C. ibiri, male, Pinkawillinie Conservation Park, South Australia (photo: E. Fothergill). (F) C. ibiri, female, Ironstone Hill Conservation Park, South Australia (photo: I. Williams). (G) C. tuniluki, male, Chinaman Flat, Big Desert, Victoria (photo: P. Robertson). (H) C. tuniluki, female, Pioneer Drive, Murray-Sunset Reserve, Victoria (photo: M. Campbell).
Four new species of Ctenophorus. Left to right for each image: holotype male, female, and two males showing variation in dorsal and ventral patterns. Left-hand images in dorsal view; right-hand images in ventral view: (A–B) C. ibiri, (C–D) C. kartiwarru, (E–F) C. tjakalpa, and (G–H) C. tuniluki. All specimens approximately 50 mm SVL.
Contributor Notes
South Australian Museum, North Terrace, Adelaide, South Australia, Australia 5000
