Diplodactylus granariensis rex Storr, 1988

Hutchinson, Mark N., Doughty, Paul & Oliver, Paul M., 2009, Taxonomic revision of the stone geckos (Squamata: Diplodactylidae: Diplodactylus) of southern Australia, Zootaxa 2167, pp. 25-46 : 35-37

Diplodactylus granariensis rex Storr, 1988

Giant Stone Gecko

Figs 8, 9 , 14 D

Diplodactylus granariensis rex Storr, 1988: 220 . Holotype WAM R 97288, 44 km southeast of Leinster, WA.

Diagnosis. A large-bodied, shorter-tailed member of the D. vittatus complex, usually lacking a rostral crease. Colour pattern includes a strongly-developed, wavy-edged to almost straight dorsal stripe, extending on to the head as a very broad bifurcate pale stripe to each eye. Upper flanks lighter and bordered below by a dark midlateral stripe.

Description ( Fig 8, 9 , 12 D). SVL 49.0–72.0 mm (mean 60.9, n=27); tailL 24.0–42.0 mm, mean 34.5, (45.2–63.3 % SVL, mean 59.8) (n=20). Supralabials 10–13 (mean 11.7, n=27), relative height of first and second supralabial generally subequal. Infralabials 10–13 (mean 11.3, n=27). Apex of rostral scale usually lacking a median division (small division evident in 4 of 27 examined). Supranasals usually in contact; a single internarial present in 3 of 27 examined. 1–4 postnasals (mean 3.1, n=27).

Dorsal colour light to medium dark brown, greyish-brown or tan. Beige vertebral stripe continuous, with margins that vary from straight to scalloped. Vertebral stripe bifurcates on the nape to form two very wide stripes ending at the eyes. Inner margins of these stripes define a relatively small inverted triangle of the dorsal body colour confined to the parietal region. Blackish paravertebral margins of vertebral stripe strongly developed, tending to merge gradually with the colouring of the upper lateral zone, but sometimes forming a broad blackish dorsolateral stripe, well demarcated from both the vertebral and lateral colours. Upper lateral zone usually with a wavy dark stripe margined by paler colouring. At most, lateral patterning consists only of scattered small lighter spots that lack obvious dark margins.

Karyotype. Unknown.

Distribution. Arid interior of Western Australia, beyond the mulga-eucalypt line and south of the Gibson Desert, from the Ophthalmia Range near Newman, southeast to near Leonora and southwest to Paynes Find ( Figs 1 , 15 ).

Similar species. Distinguished from D. g. granariensis and all other Diplodactylus by presence of a dark lateral stripe, lack of a rostral crease and larger body size.

Remarks. Storr (1988) believed the two subspecies of D. granariensis to have allopatric distributions (see also Storr et al. 1990, p. 26), and this is still the case although the apparent gap has been narrowed by subsequent collections. Recent mtDNA and allozyme studies ( Oliver et al. 2007a; Doughty et al. 2008) have shown that there are very few molecular differences between the two taxa, with D. g. granariensis being paraphyletic, the populations of D. g. rex forming a monophyletic crown group most closely related to northern populations of D. g. granariensis . Yet, D. g. rex is the most distinctive taxon morphologically within the species complex. We regard the status of rex as not yet firmly established, and so for this paper continue to recognize rex as a subspecies of D. granariensis . Continued use of subspecies helps to emphasise the very close genetic similarity between rex and geographically proximate populations of typical granariensis , in spite of obvious morphological differences. Detailed sampling in the region of overlap (running from about Mt Magnet to Leonora) would provide the specimens needed to establish whether there is gene flow between the taxa.

Figures

FIGURE 1. Map of southern Australia showing the distribution of the members of the Diplodactylus vittatus species complex described or re-described in the present study. Insets shows details of species distributions in overlap areas in Western Australia and South Australia (See Figs 15 and 16). Diplodactylus vittatus, square; D. furcosus, black cross, D. g. granariensis, circle; D. g. rex, circle with central dot, D. calcicolus sp. nov., grey cross, D. wiru sp. nov., triangle.

FIGURE 9. Variation in colour pattern in Diplodactylus granariensis rex

FIGURE 14. Species of the Diplodactylus vittatus complex in life. A, D. vittatus, Warrumbungle Range, NSW, (M. Hutchinson); B, D. furcosus, Whyalla, South Australia (T. Peters, SA Museum); C, D. g. granariensis, Newman Rock, WA (B. Maryan); D, D. g. rex, Wildara Pinnacle, WA (B. Maryan); E, D. calcicolus sp. nov., vicinity of the WA-SA border (G. Harold); F, D. wiru sp. nov. Lake Ifould, SA (P. Oliver).

FIGURE 15. Detail of distribution of D. vittatus complex in Western Australia. Note significant range overlap of D. granariensis and D. calcicolus sp. nov. in the southwest. Symbols as in Fig. 1.