Gehyra versicolor, Hutchinson & Sistrom & Donnellan & Hutchinson, 2014

Hutchinson, Mark N., Sistrom, Mark J., Donnellan, Stephen C. & Hutchinson, Rhonda G., 2014, Taxonomic revision of the Australian arid zone lizards Gehyra variegata and G. montium (Squamata, Gekkonidae) with description of three new species, Zootaxa 3814 (2), pp. 221-241 : 229-233

Gehyra versicolor sp. nov

Figs 2C–D , 3 , 6 , 7 .

Gehyra 2n=40a " variegata ”, 38a " variegata - montium ", Moritz, 1986: p. 48.

Holotype: SAMA R 51968 K, from 1.9 km SW of Reedy Hole Springs, Flinders Ranges , South Australia (30° 15’ 55ˮ S, 138° 49’ 30ˮ E), collected by J. Bice, on 19 November, 1998 ( Fig. 7A ).

Paratypes (n=28; all genotyped as ‘ Clade 5’): SAMA: R 26185, Birdsville, Qld (25° 54’S, 139° 21’E) , R 28201, 1 km S Mt Dutton , SA (27° 49’S, 135° 43’E) , R 34249, 7 km E Mount Isa, Qld (20° 43’S, 139° 43’E) , R 38930, Yudnamatana , SA (30° 10’S, 139° 17’E) , R38942, R38945, Lancoona HS, NSW (32° 22’S, 145° 53’E) , R 50277, 7 km SSE Mt Deception, Beltana Station , SA (30° 46’S, 138° 17’E) , R 51609 K, 26.1 km ENE of Mimili , SA (26° 54’ 43” S, 132° 56’ 55” E) , R 51637 K, 30.3 km WNW Indulkana , SA (26° 52’ 09” S, 133° 01’ 29” E) , R 51760 K, 1.75 km W Yudnamutana Bore , SA (30° 10’S, 139° 16’E) , R 51782 K, 10.4 km SW Yudnamutana Bore , SA (30° 14’S, 139° 11’E) , R 51912, 0.5 km NW Nudlamutana Well , SA (30° 22’S, 139° 21’E) , R 51962 K, 2.8 km W Moosha Bore , SA (30° 19’S, 138° 47’E) , R 52366, 4.7 km W Parachilna Hill , SA (31° 08’S, 138° 33’E) , R 54530, 4.5 km N Station Creek crossing, Prairie–Muttaburra road, Qld (22° 02’S, 144° 37’E) , R 54546– 47, 14 km NW Longreach on Landsborough Highway, Qld (23° 21’S, 143° 12’E) , R 55133, 2.7 km E Gluepot HS, SA (33° 45’S, 140° 09’E) , R 55268, Phosphate Hill mine, ‘ Snappy Site’, Qld (21° 53’S, 139° 59’E) , R55695–96 , 13.4 km NNE Hughenden on Kennedy Developmental Road, Qld (20° 47’S, 144° 19’E) , R 55905, 9 km N New South Wales / Queensland border on Mitchell Highway, Qld (28° 58’S, 145° 44’E) , R 57970, 30.1 km SSW Memory Bore , SA (28° 53’S, 132° 44’E) , R 63576, Mutawintja NP, NSW (31° 17’S, 142° 18’E) , R 64097, Terrapinna Springs , SA (29° 55’S, 139° 40’E) , R 64443, Mt Fitton HS, SA (28° 59’S, 139° 33’E) , R 64447, 17 km E Mt Fitton HS, SA (29° 54’S, 139° 25’E) , R 64549, 1.3 km WNW Nantawarrinna , SA (30° 49’S, 138° 58’E) , R 64863, 6.9 km WNW Arkaroola HS (30° 18’S, 139° 19’E) .

Diagnosis. Morphologically shares the external features of G. variegata (see above) but distinguished from that species by karyotype (2n=40a or 2n=38a) ( Fig. 2C–D ). As with G. variegata , G. versicolor is most similar G. montium but distinguished by grey to brown rather than more rufous dorsal colouring, with white markings that form a posterior highlight or margin on the trailing edge of the dark dorsal lines, rather than forming discrete circular dots that are not coordinated with the dark markings.

This diagnosis applies to populations of Gehyra genetically assignable to “Clade 5” of Sistrom et al. (2013).

Description. Adult snout-vent length 37–54 mm (mean = 46.7 mm, n = 29). Length of original tail 40–58 mm (mean = 110% SVL, n = 6).

Nostril bordered by rostral, first supralabial, supranasal and two subequal postnasals. Usually a single internasal scale (occasionally 2 or none) separates the supranasals above the rostral. Supralabials 8–11 (mode 9). Infralabials 7–10 (mode 9). Usually (f = 0.6) two pairs of chin shields; if a third pair is visible it is markedly smaller than the second or asymmetric, anterior pair in contact with only the first infralabial. Chin shields separated from the third and succeeding infralabials by the interpolation of a series of enlarged scales (parinfralabials) that margin the ventral edge of the infralabials. Second infralabial notched where this parinfralabial scale row starts. Scansors under pad of fourth toe divided, 7–8 (mode 8). Precloacal pores in males 10–14 (mean = 11.9, n = 15).

Most populations uniformly have the 2n=40a karyotype first reported by King (1979), but within central Australia, geographically interspersed with 2n=40a individuals, are individuals with 2n=38 karyotypes. These specimens all belong to the same clade on the basis ofsequence data. Moritz (1986) reported two variants of the 2n=38 karyotype that differ only in that the 2n=38a karyotype had pair 8 acrocentric while the 2n=38b karyotype had this pair symmetrically metacentric. Our karyotype ( Fig. 2B ) from Native Gap (a population scored as 2n=38a by Moritz 1986) has a pair 8 that is submetacentric, neither obviously acrocentric nor symmetrically metacentric, and in fact King (1979) described and illustrated his 2n=38 karyotype (later termed the “a” variant by Moritz) as having submetacentric pairs 7 and 8, as ours does. The discrepancy may be artifactual, given the variation in condensation and clarity that is typical across karyotypic preparations. In case further cryptic species are demonstrated among these populations, we have confined our type series for G. versicolor to animals from 2n=40a populations only.

In life, dorsally light to medium grey or grey-brown, generally with a complex pattern based on one or two pairs of more or less continuous dark longitudinal irregular dorsal stripes with numerous cross links and reticulations, the dark markings all coordinated with white highlights that can form irregular spots but are consistently in contact with the darker markings as in G. variegata . In general, specimens of G. versicolor , even when strongly patterned, tend to have less distinct and contrasting patterns ( Fig. 7 ) than do well marked G. variegata . Common variant patterns include one where some of the dark dorsal markings form back-swept angular or crescentic bars, each with a whitish spot contained in the angle of the bar, and another where the body is densely stippled with low contrast darker grey bars and blotches with only weakly apparent paler edges. None of these variations is unvarying and the colour patterns show continuous variation both within and between populations.

Distribution. Widespread from the Murray Valley of northern Victoria north and east through New South Wales west of the Great Dividing Range and similar areas of Queensland north to about the latitude of Hughenden. Extends west into most of South Australia, with the exception of the southern and western Eyre Peninsula and the Great Victoria Desert, and north-west into southern and central Northern Territory. Not currently known to occur in Western Australia. Found in both rocky and arboreal situations, as well as on buildings.

Comments. This species is the only one where we find two karyotypic groups appearing to belong to a single taxon. Moritz (1986) reported both 2n=40a and 2n=38 (a and b) from the MacDonnell Ranges and adjacent central Northern Territory, and at present our data suggests all belong to a single species, G. versicolor . As with the variable populations of G. moritzi , further detailed study combining the same multiple approaches used here are desirable to clarify the gene flow among these chromosomally different populations.

Similar detailed studies are needed in central and western Queensland to better understand the distribution and variation of G. versicolor and Clade 4 where they co-occur ( Sistrom et al. 2013), and the potential contact or overlap between G. variegata and G. versicolor in central western South Australia. However, it is clear that over the great majority of its distribution this is a single species, consistently different from other Gehyra . Most of the literature pertaining to the biology of “ Gehyra variegata ” (e.g., Bustard 1965, 1967, 1968, 1969; Henle 1990) actually applies to this species, as does recent population genetic work by Duckett and Stow (2010, 2013). Swan et al. (2004) report the maximum SVL for this species (as G. variegata ) as 57 mm.

Etymology. The specific name chosen here is from the Latin meaning ‘variable in colour’, appropriate for a species that shows considerable individual and geographic variation. Given the very wide distribution of the species it is somewhat surprising that no older name appears to be available for it in the synonymy of G. variegata . Cogger et al. (1983) listed several synonyms of Gehyra variegata . Subsequently, these have proven to be based on specimens attributable to other Australian Gehyra species groups, especially eastern species related to G. australis ( Bauer & Henle 1994; Shea 1995). Other possible synonyms were discussed by Sistrom et al. (2009) in reference to G. lazelli ; none apply to G. versicolor .

Figures

FIGURE 2. Karyotypes which are species-specific. A, 2n=40b, Gehyra variegata, SAMA R65764 from the Maralinga area, South Australia. Note submetacentric pairs 3 and 6. B, 2n=42b, Gehyra pulingka sp. nov, SAMA R51574 from the Amata area, South Australia. The submetacentric pair 6 with a secondary constriction is characteristic. C, 2n=40a, Gehyra versicolor sp. nov, SAMA R51790 from Yudnamutana Bore, Flinders Ranges, South Australia, with submetacentric pairs 5 and 7. B. 2n=38a karyotype, G. versicolor sp. nov, SAMA R65948 from Native Gap, SSE of Aileron, NT, with submetacentric pairs 5, 7 and 8.

FIGURE 3. Distribution of the species of the Gehyra montium - variegata complex, based on populations identified from DNA sequences. Inset shows the detailed distributions of species in the Central Ranges area.

FIGURE 6. Map showing the documented occurrence of G. variegata (dark grey) and G. versicolor sp. nov. (light grey). The inset shows the western part of the state of South Australia where distributions of the two species approach one another. Dashed line indicates the transcontinental railway line.

FIGURE 7. Gehyra versicolor sp. nov.. A. Holotype, SAMA R51968, adult male from 1.9 km SW of Reedy Hole Springs, Flinders Ranges, South Australia. B and C, adult females, SAMA R63187 and 63185 (respectively), from arboreal microhabitats at New Year’s Gift Bore, 9.6 km SW of Bopeechee, South Australia, showing strong and weak pattern variants typical of both inter- and intra-population variation for this species. D, adult male, SAMA R65588, from Witchelina Station, South Australia, with speckled patterning sometimes seen in rock dwelling populations.