Oedura elegans, Hoskin, 2019

Hoskin, Conrad J., 2019, Description of three new velvet geckos (Diplodactylidae: Oedura) from inland eastern Australia, and redescription of Oedura monilis De Vis, Zootaxa 4683 (3), pp. 242-270 : 256-259

Oedura elegans sp. nov.

Elegant velvet gecko

( Figs. 5B , 9 , 10 )

Material examined. Holotype. QM J59673 , 15 km south of Yuleba (- 26.751° S, 149.382° E, 340 m a.s.l.), 20 March 1995.

Paratypes. QM J9815 , Tambo (- 24.883° S, 146.250° E) ; QM J27190 , 39 km W of Mitchell (- 26.466° S, 147.650° E) ; QM J30319 , 16 km NE of St George (- 27.933° S, 148.700° E) ; QM J30731 , Arcadia Valley , via Injune (- 25.183° S, 148.783° E) ; QM J34621 , Alton Downs, 50-64 km W of Westmar (- 27.916° S, 149.116° E) ; QM J34796 , Moombah Stn, 64km W of Westmar (- 27.983° S, 149.300° E) ; QM J59541 , Yuleba SF (- 26.649° S, 149.435° E) ; QM J79983 , Mt Maria , 10 km NE of Morven (- 26.327° S, 147.222° E) ; QM J80149 , Warrego Hwy Stock Route, 3 km E of Morven (- 26.474° S, 147.150° E) ; QM J82946 , Gullugimbi, 15 km N of Jackson (- 26.377° S, 149.586° E) ; QM J83089 , Chesterton NP, 4.2 km N of Dog Fence (- 26.181° S, 147.328° E) ; QM J83091 , Newington, 7 km WNW of homestead (- 27.108° S, 148.954° E) ; QM J83413 , Carnarvon Stn, Mt Lyon Rd , 140 km NW of Injune (- 24.846° S, 147.747° E) ; QM J89194 , Tuktoyuktuk, 34 km SW of Injune (- 26.014° S, 148.268° E) ; QM J93736 , QM J93738 , Caves Creek Rd, Carnarvon Stn (- 24.919° S, 147.460° E) ; QM J93828 , QM J93829 , Conglomerate Spring, Carnarvon Stn (- 24.838° S, 147.781° E) .

Diagnosis. Oedura elegans sp. nov. can be distinguished from all congeners by the following combination of traits: moderately large adult size (SVL mean 77.4, max 89.4 mm); relatively long and rounded original and regrown tail (original: TL/SVL = 0.66–0.83, TW/TL = 0.13–0.18, TD/TW = 0.63–0.74; regrown: TL/SVL = 0.60–0.76, TW/ TL = 0.18–0.22, TD/TW = 0.71–0.81); relatively narrow head (HW/SVL = 0.17–0.18); rostral scale only partially divided by medial vertical groove; single cloacal spur on each side; moderate number of interorbital scales (17–21); <18 pre-cloacal pores in males (mean 15, range 13–17), split medially by 1–3 scales without pores; iris copper coloured; unbroken pale bar on the nape; dorsal colouration consisting of a vertebral series of paired, connected white spots (dumbbells), each surrounded by thin dark edging and not connected to each other; dorsal background and lateral surfaces evenly flecked; no broad dark band connecting back of eye to nape marking; no spots on limbs; original tail with paired white spots along dorsal midline.

Particulars of the holotype ( Fig. 9 ). QM J59673 , male, SVL = 76.5 mm; original tail; TL = 57.2; TW = 9.7 mm; TD = 6.7 mm; AG = 32.4 mm; FL = 7.9 mm; HLL = 11.4 mm; NL = 19.8 mm; HL = 17.3 mm; HW = 13.8 mm; HD = 7.0 mm; S = 7.5 mm; Eye = 3.6 mm; 18 interorbital scales; 10 supralabials; 10 infralabials; 2 scales contacting dorsal edge of rostral; rostral crease 80% of rostral depth; 6 scales bordering nostril; cloacal spurs 1/1; toe subdigital lamellae counts: I 7, II 7, III 8, IV 8, V 7 ; finger subdigital lamellae counts: I 6, II 6, III 7, IV 7, V 6 ; 16 pre-cloacal pores, with series separated medially by 2 scales without pores .

Description of type series. Data for size, shape and scalation is presented in Table 1. A moderately large (SVL 66.5–89.4 mm, mean 77.4 mm) and moderately robust (AG/SVL 0.42–0.49) Oedura . Body slightly depressed, covered in small granular scales; scales on ventral surface about the same size as those on dorsum; 1 spur positioned laterally on either side of the cloaca in both sexes, typically more well-defined in males; row of 13–17 (mean 15.1) pre-cloacal pores in mature males, divided medially by 1–3 granular scales without pores, line of pores extending to underside of each thigh; pre-cloacal pores not evident in females; neck broad and moderately long (NL/SVL = 0.20–0.26). Head distinct from neck; moderately long (HL/SVL = 0.21–0.24; S/HL = 0.41–0.47), relatively narrow (HW/SVL = 0.17–0.18) and moderately depressed (HD/SVL = 0.08–0.11); covered in small granular scales that are slightly larger on the dorsal and lateral surfaces of the snout; scales rounded to hexagonal; interorbital counts 17–21 (mean 18.9); rostral scale approximately twice as wide as deep, divided 20–80% (mean 40%) vertically by a medial groove; rostral contacting nostril, bordered by 2 (rarely, 3) scales along its dorsal edge, and bordered laterally on each side by the first supralabial scales; 6 scales contacting nostril; supralabials 9–11 (mean 10.2); first supralabial narrower than second supralabial; infralabials 9–11 (mean 10.1); enlarged scales extending back from mental scale, starting as relatively large and hexagonally-shaped and decreasing in size and becoming rounded on throat; ear opening small and diagonally elongate, or occasionally rounded; eye relatively large (Eye/SVL = 0.040 –0.051). Limbs moderately long (FL/SVL = 0.10–0.13; HLL/SVL = 0.13–0.15); digits dorsoventrally compressed, with enlarged subdigital lamellae in a series that starts with relatively small and undivided scales and increases in size and width to become paired, obviously expanded scales; the penultimate pair is slightly narrower; the apical pair is obviously enlarged and separated from the series; 3 rd toe subdigital lamellae counts 7–9 (mean 7.9) (including apical pair); 3 rd finger subdigital lamellae counts 6–7 (mean 6.9) (including apical pair). Original tail moderately long (TL/SVL = 0.66–0.83) and narrow (TW/TL = 0.13–0.18); tapered; only slightly depressed (TD/TW = 0.63–0.74); scales arranged in concentric rings, about the same size on the dorsal and on ventral surfaces. Regrown tail moderately long (TL/SVL = 0.60–0.76) and narrow (original TW/TL = 0.18–0.22); tapered; slightly depressed (TD/TW = 0.71–0.81); scales arranged in concentric rings, about the same size on the dorsal and ventral surfaces. Colouration in spirit. Dorsal pattern consists of prominent series of 6 or 7 pale markings from the nape to the hips. The first of these is a nape bar that is typically unbroken (rarely, broken in the centre) and shaped as an arc that extends forward towards the temporal region, sometimes with a white spot immediately anterior on the posterior temporal region. The following 5 or 6 dorsal markings are a series of paired white spots along the dorsal midline. The spots in each pair are either tightly abutting or the white is interconnected, and hence they are shaped as dumbbells. The pale dorsal markings each have a black border that is typically less than half the width of the pale marking. The dark edging has a discrete inner boundary against the pale marking but a slightly diffuse outer boundary against the background colour. Each of these dark-edged, pale dorsal markings is discrete (i.e., not joined by dark markings to adjacent markings in the series). Prominent markings are completely restricted to this dorsal series, with all other dorsal and lateral surfaces being pale beige with fine, brown flecking or stippling. A dark band extends from the naris to the eye, and then extends from below the back of the eye as a thin, obscure line that goes over the top of the ear opening to below the nape bar. This thin dark line may touch the lower black edging of the nape bar but does not clearly run into it. Temporal region otherwise finely flecked with dark markings, sometimes with one or two small white, darkedged spots. The dark band from naris to eye is bordered below by a white line along the labial scales that continues through the ear opening and along the neck towards the insertion of the forelimb. The top of the head is pale with a network of irregular, dark lines extending out from the centre. Top of eyes grey. Snout pale, with a thin, dark line extending from the rostrum along the centre of the snout and typically splitting to connect to the anterior corner of each eye. Iris dark with a milky, opaque surface. The original tail is a continuation of the dorsal pattern, with dark-edged white dumbbells extending along the length, on a mottled or finely flecked background. Spots in each dumbbell typically more heavily connected than those on back, sometimes appearing as one blotch. The regrown tail is pale with heavy, dark flecking or mottling. The limbs are as for the dorsal and lateral background—beige with even, fine flecking or stippling. All ventral surfaces even, yellowish cream, except the underside of the tail which is either yellowish cream or marked with a diffuse version of the dorsal and lateral tail pattern (particularly for regrown tails). Cloacal spur pale.

Colouration in life ( Figs. 5B , 10 ). As described above but with the following differences. The nape bar and dumbbells along the midline of the back and original tail are all bright white in life. The dark edging on these markings is also more prominent, particularly along the interior edge against the white marking. The dark markings on the head and the fine, black flecking and stippling on the body and limbs are darker in life and sometimes have a purplish tinge. The background colour in life is similar to that in spirit but is yellowish or pinkish rather than beige. The background colour of the original and regrown tails is yellow. Ventral surfaces in life are cream or pinkish white, except on the tail where there is typically some indication of the dorsal and lateral tail pattern. Cloacal spur white. Iris is dark copper coloured. The labial scales in life are yellowish cream. Juvenile pattern is similar to adults but the dorsal markings appear more pronounced on a background that is pinkish and has more diffuse flecking/stippling. ( Fig. 10F ).

Comparison with other species. See the Comparison for O. monilis , above, for comparison with congeners outside the tryoni group.

Within the tryoni group, O. elegans sp. nov. is readily distinguished from O. castelnaui and O. argentea by having a nape bar enclosed in black (versus full nuchal band in those species) and dorsal pattern of blotches and bars (versus full body bands in those species) ( Fig. 2 ). Distinguished from O. coggeri by lack of white spots on limbs (versus obvious white spots), larger body size (max 89.4 mm versus 80.7 mm), narrower head (HW/SVL 0.17–18 versus 0.19–0.22), longer original and regrown tail ( Table 1), and original tail pattern of paired blotches on the dorsal midline (versus irregular white bands). Distinguished from O. tryoni by, typically, unbroken bar on nape (versus many spots or few blotches), dorsal pattern restricted to paired, large blotches (dumbbells) on midline (versus, typically, evenly spotted or blotched), lack of white spots on limbs (versus usually spots at least on hindlimbs), smaller body size (max 89.4 mm versus 103.1 mm), narrower head (HW/SVL 0.17–0.18 versus 0.17–0.22), lower interorbital count (typically <20 versus typically> 20), and, typically, lower number of pre-cloacal pores in males (typically 17 or less versus typically 17 or more) ( Tables 1, 2).

Differs from O. monilis in having a thin black line running from below the back of the eye to below the nape marking (versus a dark band running from the back of the eye to the nape marking), dorsal markings surrounded by thin black edging but nape bar and none of the dumbbells connected to each other (versus black markings connecting at least the nape bar and anterior-most dorsal markings), prominent markings restricted to dorsal midline, with no spots on lateral surfaces (versus at least some indication of obscure white spots on mid-lateral line), original tail pattern of paired blotches on dorsal midline (versus irregular bands), head relatively narrow (versus head broad), original and regrown tail relatively longer and narrower ( Tables 1, 2).

Differs from O. picta sp. nov. in having prominent dorsal markings restricted to the midline (versus more evenly spread across dorsum), original tail pattern of paired blotches on dorsal midline (versus irregular bands), iris typically dark copper coloured (versus gold), larger size (max 89.4 mm versus max 79.7 mm), head shorter (HL/ SVL 0.21–0.24 versus 0.23–0.26) and narrower (HW/SVL 0.17–0.18 versus 0.18–0.21), and regrown tail narrower (TW/TL 0.18–0.22 versus 0.21–0.28) ( Tables 1, 2).

Differs from O. lineata sp. nov. in having an unbroken nape bar (versus V- or Y-shaped broken bar), dorsal pattern of paired dumbbells along midline (versus linearly-arranged lines, spots and black markings on either side of thin, pale midline), lateral surfaces finely flecked (versus heavily marked with white spots and black markings), a thin black line running from below the back of the eye to below the nape marking (versus a dark band running from the back of the eye and usually to the nape marking), hindlimbs mottled (versus usually small white spots on at least base of hindlimbs), larger size (max 89.4 mm versus max 79.0 mm), relatively more flattened original tail (TD/TW 0.63–0.74 versus 0.79–0.81), lower interorbital count (17–21 versus 21–23), lower number of supralabials (9–11 versus 11–13), and series of pre-cloacal pores in males generally separated by fewer scales medially (1–3 versus 2–6) ( Tables 1, 2).

Etymology. From the Latin elegans , meaning elegant; in reference to the fine pattern and form of this species.

Distribution. Known from many sites in inland southern Queensland and northern New south Wales ( Fig. 1 ), from the Carnarvon National Park region in the north to the Dubbo area in the south.

Ecology. Oedura elegans sp. nov. occurs in dry woodlands, particularly complex woodlands with cypress pines and shrubby elements. Arboreal; individuals are typically found at night foraging on stems and branches of trees or shrubs, or on fallen timber.

Conservation. Extensive clearing across its range has greatly reduced the area of habitat but the species as a whole is not threatened because it persists at many sites, including a number of national parks and state forests. However, it is probably regionally threatened in areas of its range that have been subject to the most intensive clearing (e.g., Goondiwindi–Narrabri region).

Figures

FIGURE 1. Map of Queensland and northern New South Wales, showing localities for species in the tryoni group (coloured circles and stars) and the two other Oedura species occurring in the region (open black symbols). Select towns and cities are also shown for reference.

FIGURE 2. Comparison of O. jowalbinna (A), O. cincta (B), O. castelnaui (C), and O. argentea (D). Photos: Stephen Zozaya (A, B); Conrad Hoskin (C, D).

FIGURE 5. Comparison of typical-looking O. monilis (A), O. elegans sp. nov. (B), O. picta sp. nov. (C), and O. lineata sp. nov. (D). Photos: Conrad Hoskin.

FIGURE 9. Holotype of O. elegans sp. nov. (QM J59673; 15 km south of Yuleba, Queensland). Photo: Conrad Hoskin.

FIGURE 10. Variation in O. elegans sp. nov.: Yuleba State Forest, Qld (A, B), St George, Qld (C), Pilliga, NSW (D), Warrumbungle National Park, NSW (E), and Yuleba State Forest, Qld (F). A–E are adults and F is a juvenile. Photos: Conrad Hoskin (A, F); Stephen Zozaya (B–D); Steve Wilson (E).