Oedura nesos OLIVER, JOLLY, SKIPWITH, TEDESCHI & GILLESPIE, 2020
Find more photos by Google images search:
Higher Taxa | Diplodactylidae, Gekkota, Sauria, Squamata (lizards: geckos) |
Subspecies | |
Common Names | |
Synonym | Oedura nesos OLIVER, JOLLY, SKIPWITH, TEDESCHI & GILLESPIE 2020 |
Distribution | Australia (Northern Territory: Groote Eylandt) Type locality: Cave Paintings Recreation Area (13.97322°S, 136.50316°E) Groote Eylandt, Northern Territory, Australia |
Reproduction | |
Types | Holotype. NTM R38578, adult female with original tail, and liver samples stored in ethanol, collected by Graeme Gillespie and Jaime Heiniger on 14 November 2016. Paratypes. (n=12) All from Groote Eylandt, Northern Territory, Australia. NTM R38576 & R38582 same locality and date as holotype; NTM R38579–R38581 from sandstone outcrop 700 m north of Alyangula (13.8412°S, 136.42305°E) collected 16 November 2016; NTM R38583 from sandstone outcrop adjacent to Umbakumba Rd (13.93050°S, 136.4945°E) collected 17 November 2016; NTM R38577 from sandstone outcrop adjacent to Umbakumba Rd (13.8927°S, 136.5112°E) collected 17 November 2016; AMS R138727–8, Groote Eylandt (13.8299°S, 136.4200°E); NTM R7494 & R7495, Umbakumba Rd (13.8799°S, 136.5000°E); NTM R7541, Ayakamindadina (13.97°S, 136.60°E). |
Diagnosis | Diagnosis. Differs from all Oedura in the following combination of characters: moderate size (to 85 mm SVL); head moderately wide (HW/SVL 0.18–0.20) and flattened (HD/SVL 0.07–0.12); tail short (TL/SVL original 0.52–0.62, regrown 0.45–0.54), transversely flattened (shallower than body), much narrower than head (TW/HW 0.59–0.77) and tapering gradually to tip; rostral 50% or less divided; postcloacal spurs 2 or 1 on each side (mode 2); 16 precloacal pores in adult males; head colouration dark brown with pale whitish-yellow supraoculars and canthal stripe absent or indistinct; and dorsal colouration of adults including five moderately well-defined whitish bands (including nuchal band), usually with greyish central shading, alternating with wider regions of extensive yellow splotching on a dark brown background (Oliver et al. 2020). Comparisons. Oedura nesos sp. nov. differs from its three closest relatives in the Oedura marmorata complex from northern Australia in aspects of tail morphology (both original and regrown) and colour pattern (Figs. 2–4). Oedura nesos sp. nov. was formerly confounded with Oedura bella, from which it differs in having a dorsal pattern including alternating transverse bands of white then regions of brown heavily blotched with yellow (versus yellow dots coalescing into distinct to indistinct yellow bands; Figs. 3–4), and in having no or a very indistinct and wavy canthal stripe (versus clearly defined, narrow, straight and continuous or near continuous canthal stripe; Figs. 3–4). Oedura nesos sp. nov. differs from Oedura gemmata in its smaller size (SVL 70–85 mm versus 84–103 mm), in having a tail (original or regrown) much narrower than the head (TW/HW 0.59–0.77 versus 0.75–1.08), and in having prominent white bands and large yellow splotches on the dorsum (versus smaller yellow or white spots only). Oedura nesos sp. nov. differs from Oedura marmorata in its smaller size (SVL 70–85 mm versus 77–97 mm), and in having a tail (original or regrown) that is much narrower than the head in dorsal perspective versus nearly as wide to wider than head (TW/HW 0.59–0.77 versus 0.76–1.2) and gradually tapering to the tip (versus sharply tapering to attenuated tip; Fig. 2–4). It can be further differentiated from geographically proximate populations of Oedura marmorata in eastern Arnhem Land by having yellowish-white supraoculars in life versus bright yellow supraoculars in life (Fig. 2), and tending to have a tail that is highly depressed in cross-section and shallower than body versus a tail that is comparatively rounded in cross-section and as deep or deeper than the body (Fig. 3–4). Hatchling and small juvenile Oedura nesos sp. nov. are easily distinguished from juveniles of its two relatives in the Oedura marmorata complex with a similar colour pattern (Oedura bella and Oedura marmorata) from northern Australia by having white bands (versus yellow; Fig. 3). Of the other species that are more phylogenetically divergent and geographically distant, Oedura nesos sp. nov. differs from Oedura cincta De Vis, 1888, Oedura fimbria Oliver & Doughty, 2016, and Oedura luritja Oliver & McDonald, 2016 (three arid-zone taxa also formerly included in Oedura marmorata) in its smaller size (SVL 70–85 mm versus 78–108 mm O. cincta, 71–104 mm O. fimbria, 85–99 mm O. luritja), and shorter tail (original tail TL/ SVL 0.52–0.62 versus 0.61–0.87) which is also distinctly flattened in cross section (versus rounded). Oedura nesos sp. nov. differs from the three Oedura endemic to the Kimberley region of north-western Australia as follows: from Oedura gracilis King, 1984 by its short and transversely flattened tail (versus very long tail that approaches length of body) and higher number of paired lamellae on the digits (more than 4 versus less than 4) arranged in slightly flared series (versus tapering); and from both Oedura filicipoda King, 1984 and Oedura murrumanu Oliver, Laver, Melville & Doughty, 2014 in its smaller size (max SVL 85 mm versus 100–110 mm), in having narrower proximal subapical lamellae on fingers 3–4 (not wider than the apical lamellae versus distinctly wider), and further differs from the former species in having a tail that is not wider than the head (versus wider). Oedura nesos sp. nov. is distinguished from all nine remaining Oedura in eastern Australia by having 2 postcloacal spurs on at least one, and usually both sides, of the tail base (versus usually 1) and having a tail that is deeply depressed in cross-section (versus subcircular). Oedura nesos sp. nov. further differs from a subset of these nine eastern Australia Oedura species by having a dorsal colour pattern consisting of five distinct relatively straight edged whitish bands (versus pale v-shaped transverse bands in Oedura castelnaui Thominot, 1889, distinct darkedged ocelli or transverse blotches of varying size in Oedura coggeri Bustard, 1966, Oedura elegans Hoskin, 2019, Oedura lineata Hoskin, 2019, Oedura monilis De Vis, 1888, Oedura picta Hoskin, 2019, and Oedura tryoni De Vis, 1884, or two pale bands across the nape and base of tail in Oedura jowalbinna Hoskin & Higgie, 2008). Oedura nesos sp. nov. further differs from the remaining eastern Australian taxon Oedura argentea Hoskin, Vanderduys & Zozaya, 2018 in having a dark blackish-brown iris in life (versus silvery) (Oliver et al. 2020). |
Comment | Conservation. Oedura nesos sp. nov. appears to be restricted to sandstone outcrop habitats on Groote Eylandt. These habitats are only approximately 43, 919 ha (439 km2) in extent; however, they are not under any foreseeable threat. Currently, manganese mining operations on Groote Eylandt do not pose a threat to Oedura nesos sp. nov. because manganese deposits are mostly found beneath flat, lateritic soils away from the sandstone escarp- ment. Where the species has been found it appears to be locally common. Oliver et al. therefore tentatively recommend that it be listed as Least Concern. |
Etymology | Nesos (Greek) meaning island, in reference to the insular distribution of this species. Used as a noun in apposition. |
References |
|
External links |