Oedura bella Oliver & Doughty, 2016, sp. nov.
Creators: name: Oliver, Paul M.
name: Doughty, Paul
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Reptilia
Squamata
Diplodactylidae
Oedura
Oedura bella

description: Oedura bella sp. nov.
Gulf marbled velvet gecko Figs. 5, 7, 8
Holotype. QM J94016 (field number—OMAR #001), adult male with original tail, 10 km south of Mt Isa on Boulia Road, Queensland, Australia (20.8617°S, 139.4617°E), collected by P.M. Oliver, M. Vucko and M. Vickers, on 20 February 2007.
Paratypes. Northern Territory: AMS R53437–8, 37 km north of McArthur River base camp on Borroloola Road (16.10°S, 136.12°E); AMS R53467, Caranbirini Water Hole, 21 km north of McArthur River base camp (16.22°S, 136.15°E); AMS R53643, Glyde River, 10 km east of McArthur River base camp (16.43°S, 136.17°E); AMS R53782, 37 km north of McArthur River Camp (16.10°S, 136.12°E); SAMA R34188, McArthur River Station (16.67°S, 135.85°E). Queensland: NTM R21288, Musselbrook Reservoir (18.61°S, 138.08°E); SAMA R34208–9, SAMA R35425, Lawn Hill NP (18.58°S, 138.50°E); QM J52748, Lawn Hill Station, Century Project Site (18.75°S, 138.58°E); QM J74927, Hells Gate (17.47°S; 138.37°E); QM J75207 –8, Lawn Hill (18.71°S, 138.48°E).
Referred material. AMS R138727–8, Groote Eylandt (13.83°S, 136.42°E); NTM R7494–5, Umbakumba Rd (13.88°S, 136.50°E); NTM R7541, Ayakamindadina (13.97°S, 136.60°E).
Diagnosis. A medium-sized (SVL: mean 78 mm, max 92 mm) species in the O. marmorata complex with a wide (HW/SVL 0.19–0.23) and moderately deep head (HD/SVL 0.10–0.12), short body (Trk/SVL 0.41–0.49), short original tail (TL/SVL 0.49–0.65) that is narrower than head and slightly depressed, rostral usually less than half divided, terminal lamellae moderately wide (ToeW/SVL 0.021–0.030), proximal subdigital lamellae of all fingers not wider than apical pair, 12–17 precloacal pores in males and base colouration dark purplish brown with 5 distinct to faint light dorsal bands from nape to hindlimbs.
Description. A medium-sized (to 92.0 mm SVL) and moderately robust Oedura (Trk/SVL 0.41–0.49). Head moderately narrow (HW/SVL 0.19–0.23) and not strongly depressed (HD/SVL 0.10–0.12). Rostral 25–50% divided, bordered dorsally by two internasals, internasals bordered dorsally by two oblong moderately enlarged supranasals and 1–3 (mode 1) smaller intervening scales. Enlarged supralabials 9–10 to midpoint of eye, 11–13 in total; infralabials 9–13. Limbs moderately long (ArmL/SVL 0.12–0.15; LegL/SVL 0.14–0.16). Subdigital lamellae moderately expanded and prominent, 7–8 rows (mode 8) under finger three and 7–9 toe three, distal lamellae on all digits either divided or deeply notched, apical distinctly larger and generally wider than more proximal pairsespecially on fingers, proximal lamellae undivided. Enlarged postcloacal spurs 2 or 3, in a single cluster per side. Original tail relatively short (TL/SVL 0.49–0.65) and wide (TW/TL 0.18–0.28), gradually tapering to a point, slightly depressed in cross-section and slightly concave ventrally; moderately wide but shows considerable variation depending on body condition (TW/SVL 0.10–0.15), scalation relatively homogeneous with dorsal and ventral scales of similar size. Fully regrown tails shorter (TL/SVL 0.44–0.53) and wider (TW/TD 0.21–0.31) than original tails.
In preservative, dorsal colouration of adults variable; base colouration dark purplish brown, with 5 distinct to very indistinct broad light bands from nape to hindlimbs, with a further 4–7 similar bands on the tail. Light bands with little to extensive dark brown flecking or blotches; on larger specimens dark brown pigmentation is extensive such that the broad light bands are reduced to two narrow indistinct and often broken bands. The anterior (nuchal) light band extends across the nape and joins or approaches a light lateral band extending from the labial scales and above the tympanum. The canthal stripe ranges from distinct to indistinct. Dark brown regions between light bands and elsewhere on the dorsal and lateral surfaces of the head, torso, limbs and tail, with extensive further light flecking and blotches. Venter relatively plain light buff with a very faint wash of light brown, particularly towards the lateral extremities and on the head and limbs, more extensive brown mottling also present along the ventrolateral edges of the tail. Regrown tails dark brown with varying amounts of light flecking, but no clear pattern.
Hatchlings and small juveniles lack light flecking and generally have a very simple pattern of five sharplydefined light bands on the neck and body, and 5–7 light bands on the tail, separated by broad plain dark brown regions. As specimens grow, the sharp definition of light and dark regions decreases, and the amount of light flecking and blotching across the body increases.
In life, the base colouration of adults is dark purplish brown during the day, washed out grey at night; light bands and flecks ranges tend to be bright yellow. The canthal stripe tends to be very strongly defined and a white labial stripe is also sometimes clearly apparent. Iris very dark brown.
Particulars of holotype. QM J94016 (field tag number—OMAR#001), male with original tail (in mm): SVL 77.0, HW 14.6, HD 7.4, HL 19.6, EN 6.3, IN 2.8, IO 6.7, EYE 5.0, TrK 31.0, ArmL 10.1, LegL 10.9, TL 38.0, TW 8.3, TD 5.6, 3FW 1.8, 3TW 2.3. Scales: RC 25%, SuL 12(10), InF 11, CS, 3FL 7, 3TL 8, precloacal pores 16.
Distribution and habitat. Restricted to the ranges around the south and western edges of the Gulf of Carpentaria; from the Selwyn Range around Mt Isa in the southeast, north to Riversleigh and Musselbrook regions in the Queensland-Northern Territory border, as far west as the McArthur River and Borroloola regions of Northern Territory, with a further apparently isolated insular population on Groote Eylandt to the north (see comments), and another isolated record from the northern edge of the Barkly Tablelands (Fig. 2).
Field observations suggest this species is primarily saxicoline, using both horizontal screes and vertical faces (including road cuttings), however, it has also been recorded under bark around the base of trees (but in rocky country) (G. Bourke, pers. comm.).
Etymology. From the Latin masculine adjective bellum (used in its feminine form), meaning amongst other things pretty, handsome, charming, fine, lovely, neat, pleasant, agreeable, active, gallant or good. In reference to the very attractive contrasting yellow and dark colour pattern of this species.
Comparisons. Oedura bella is similar to parapatric populations of O. marmorata in northern Australia (although it differs in both nuclear and mitochondrial loci). It differs in external morphology by possessing an original or regrown tail that is much narrower (TW/SVL 0.10–0.15 versus 0.19–0.24) and generally less than the width of head, and O. bella also reaches a smaller maximum size, although adult sizes overlap (adult SVL usually 77–92 mm versus 77–97 mm) and sample sizes are low.
Oedura bella differs from O. cincta and Western (see below) by the combination of its smaller maximum size (SVL 64–92 mm versus 77–106 mm), shorter original tail (TL/SVL 0.49–0.65 versus 0.58–0.80), and its narrower terminal lamellae (0.21–0.30 versus 0.23–0.36) and narrower lamellae series on the fingers (not wider than terminal lamellae versus wider on digits 3 and 4). It further differs from the geographically proximate Oedura cincta by generally having a rostral partially divided by a crease (versus usually fully divided).
Oedura bella can be distinguished from the three species of Oedura in the Kimberley region in Western Australia by having subdigital lamellae that are slightly expanded around the midpoint of the digit (versus strongly tapering in O. gracilis King, 1984, or obviously flared and often as wider or wider than the apical lamellae in O. filicipoda King, 1984 and O. murrumanu Oliver, Laver, Melville & Doughty, 2014), and its moderately long and slightly swollen tail (versus very long [approaching length of body] and tapering in gracilis, or greatly flattened and wider than body in O. filicipoda and O. murrumanu). With a maximum SVL of 92 mm, O. bella is also smaller than O. filicipoda and O. murrumanu (which both regularly exceed 100 mm).
Oedura bella differs from all other Oedura in eastern Australia by possessing more than one postcloacal tubercle and in having a base colouration of five relatively thin dorsal bands. The latter character distinguishes it from two other small saxicoline Oedura in eastern Australia: O. coggeri has large ocelli on limbs and torso and O. jowalbinna has a pale pinkish gray dorsum with distinct dark-edged bands across the neck and base of tail and a plain yellow original tail (Hoskin & Higgie 2008). All other Oedura in eastern Australia tend to be larger (SVL> 90 mm) and also have dorsal patterns that do not feature thin light bands; specifically, O. castelnaui has wide bands, O. monilis has blotches or ocelli, and O. tryoni has dense small spots.
Remarks. No genetic samples were available from the Groote Eylandt samples that we refer to this species. Given their geographic disjunction from all other material, the distinctiveness of this population warrants further investigation.
description: Published as part of Oliver, Paul M. & Doughty, Paul, 2016, Systematic revision of the marbled velvet geckos (Oedura marmorata species complex, Diplodactylidae) from the Australian arid and semi-arid zones, pp. 151-176 in Zootaxa 4088 (2) on pages 165-168, DOI: 10.11646/zootaxa.4088.2.1, http://zenodo.org/record/258925