Diplodactylus wiru, Hutchinson, Mark N., Doughty, Paul & Oliver, Paul M., 2009

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 : 39-42

Diplodactylus wiru sp. nov.

Desert Wood Gecko

Figs. 12, 13 , 14 F

Diplodactylus 'GVD' Oliver et al., 2007a

Holotype. SAMA R59908, adult male, from 15 km S of Mount Finke, SA (31º 02' 02" S, 134º 02' 45" E), collected by D. Armstrong on 27 November 2004 ( Fig. 10).

Paratypes. South Australia ( SAMA specimens): R18202 (F) SW Wyola Lake (29º 30' S, 130º10' E); R31848 (F) 17 km ESE Mt Christie Siding (30º 37' 37" S, 133º17' 04" E); R31863 (M) 15 km SSE Mt Christie Siding (30º 37' 31" S, 133º 15' 46" E); R31942 (F) 20 km N Wallala Hill (32º 08' 40" S, 134º 40' 20" E); R31946 (M), R31947 (M), R31951 (M) S Inila Rock Waters Yumbarra Conservation Park (31º 48' 14" S, 133º 24' 05" E); R31963 (F) 1.5 km S Inila Rock Waters Yumbarra Conservation Park (31º 47' 42" S, 133º 25' 44" E), R32052 (M) 5.5 km S Immarna Siding (30º 33' 07" S, 132º 08' 42" E); R32097 (F) 9.5 km WNW Immarna Siding (30º 29' 16" S, 132º 03' 35" E); R45552 (M) 6 km NNE of Inila Rock Waters Yumbarra Conservation Park (31º 43' 47" S, 133º 27' 02" E); R57217 (M) 23.9km E Vokes Hill Corner (28º 34' 16" S, 130º 55' 31" E); R59458 (M) Maralinga (29º 46' 14" S, 131º 06' 29" E); R61154 (M) Lake Ifould area (30º 52' 17" S, 132º 15' 47" E); R62000 (M), R62001 (M), Moonaree (31º 57' 41" S, 135º 40' 33" E); R62293 (M) Noorina (28º 30' 30" S, 129º 12' 37" E); R62367 (M) Vokes Hill (28º 32' 25" S, 130º 02' 49" E); R62465 (F) Childara rockhole (31º 36' 18" S, 134º26' 48" E).

Western Australia ( WAM specimens): R 100622, R135291 (M) 25 km NNE Queen Victoria Spring (30º 14' S, 123º 43' E); R157876 (30º 14' S, 123º 43' E).

Diagnosis. A moderate-sized member of the D. vittatus complex, showing relatively little variation compared with other members of the complex. Well-developed, almost straight-edged to zigzag dorsal stripe always present, broadly bordered by black; light dorsal colour extends on to occiput as a pale cap with somewhat darker centre, but no well-defined bifurcate pattern; flanks dark grey with one or more rows of well-defined, dark-edged circular spots.

Description ( Figs 12, 13 , 14 F). SVL 41.0–59.5 mm (mean 54.0, n=23); tailL 32.0–39.0 mm, mean 35.5 (56.1–67.3% SVL, mean 61.9) (n=11). Supralabials 11–14 (mean 11.9, n=11), first supralabial generally higher than the second. Infralabials 10–14 (mean 11.3, n=11). Apex of rostral scale with median division descending to about the mid-height of the scale (absent in one specimen). Supranasals in contact (13/23), separated by a single internarial (8/23) or separated by two internarials (2/23). 2–4 postnasals (mean 3.2, n=23).

Dorsal colour medium to dark brownish grey. Beige vertebral stripe almost always continuous, but with strongly scalloped margins; less scalloped to almost straight-edged in a minority of specimens. Vertebral stripe expands to a pale cap on the head, colour uniform or with at most a weakly evident darker parietal patch. Blackish paravertebral margins of vertebral stripe strongly developed, tending to merge laterally with the colouring of the upper lateral zone. Upper lateral zone usually well marked with a series of relatively large dark-edged, circular spots (the dorsal edge is often heavier marked than the ventral edge of the spots) and sometimes with a dorsolateral series of smaller spots. Apart from the prominent spots, the upper background colour of the upper lateral zone is uniform, without a peppering of lighter or darker scales. Ventral surface offwhite.

Karyotype. 2n=38, all acrocentric ( King 1977).

Distribution. Southern Great Victoria Desert and adjacent sandy habitat blocks. Records extend southwest to Norseman, WA, and east to the Lake Acraman area, Gawler Ranges, SA ( Figs 1 , 15 , 16 ). Northern limits appear to be at about the level of the Serpentine Lakes, SA. Absent from the Nullarbor Plain. The absence of D. wiru sp. nov. from the area immediately west of the WA border likely represents a gap in collecting effort.

Etymology. The specific epithet is an adjective from the western desert languages (e.g. Pitjantjatjara, Ngaatjatjarra), wiru meaning 'beautiful' or 'fine' ( Goddard 1996); chosen to highlight the bold markings of this species.

Similar Species. Distinguished from sympatric and parapatric species as follows: from D. granariensis by the presence of a well-defined dark-edged light lateral spots arranged in one or more longitudinal series and absence of a bifurcate pattern on the occiput, and the first supralabial consistently taller than the second; from D. furcosus by the pale occipital cap rather than a bifurcate occipital marking and the blackish outlines to the light dorsal markings thick and often merging into the dorsal background colour, rather than narrow and sharply distinct from the dorsal background colour; from D. calcicolus sp. nov. by the continuous, regularly arranged dorsal stripe and lateral series of spots rather than large irregular blotches, and unicoloured rather than minutely variegated background colour of the flanks.

Remarks. Specimens pit-trapped or observed at night have been associated with large mallee eucalypts with extensive ground litter of fallen bark, branches and leaves. Unlike syntopic species of Lucasium ( L. damaeum Lucas and Frost, 1896 and L. bungabinna Doughty and Hutchinson, 2008 ) which were generally found in open sandy patches, specimens of D. wiru sp. nov. appeared to stay close to woody debris and ‘cluttered’ understorey cover (MNH, PMO, pers. obs.). The distributional pattern of D. wiru sp. nov. is highly congruent with those of a number of species that occur in a narrow band of sandy mallee vegetation communities that lie between the semiarid south coast and hinterland and the Great Victoria Desert ( Doughty & Hutchinson 2008).

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 13. Variation in colour pattern in Diplodactylus wiru sp. nov. Middle specimen is a juvenile.

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.

FIGURE 16. Detail of distribution of D. vittatus complex in South Australia. Note significant range overlap of D. furcosus and D. calcicolus sp. nov. on Eyre Peninsula, and the two regions (arrowed) where three species are sympatric. Symbols as in Fig. 1.