Eremiascincus rubiginosus MECKE & DOUGHTY, 2018
Can you confirm these amateur observations of Eremiascincus rubiginosus?
|Higher Taxa||Scincidae, Sphenomorphinae (Sphenomorphini), Scincoidea, Sauria, Squamata (lizards)|
|Common Names||E: Rusty skinks|
|Synonym||Eremiascincus rubiginosus MECKE & DOUGHTY 2018|
|Distribution||Australia (Western Australia: Pilbara region)|
Type locality: Dale’s Gorge, Karijini National Park, Western Australia (22.48103°S, 118.56453°E; Fig. 1E)
|Types||Holotype: WAM R174519 (Figs. 1A–D), adult female, collected by R.J. Ellis, P. Doughty & A.M. Bauer on 16 August 2014. Paratypes. WAM R129631, unsexed juvenile, gorge 120 km northwest of Newman (22.9166°S, 118.8833°E), collected 21 April 1997; WAM R157584, adult female, cave in a gorge near Robe River (21.6783°S, 114.8817°E), collected 18 May 2004; WAM R164205, adult male, rocky gully 48 km south-southwest of Pannawonica (22.0475°S, 116.1872°E), collected 23 June 2007; WAM R172373, adult female, 10 km southwest of Rio Tinto Hope Downs, collected 14 April 2011; WAM R174598 and WAM R174599, adult females, Dale’s Gorge, Karijini National Park (22.47698°S, 118.56302°E), collected 14 March 2015; WAM R174852, adult female, cave near Red Hill Creek, 30 km south-southeast of Pannawonica (22.08139°S, 116.27583°E), collected 20 May 2015.|
|Diagnosis||Diagnosis: A moderate-sized Eremiascincus (adult SVL 60–82 mm) with usually seven supralabials (rarely six or eight), three pairs of chin shields, a moderate-sized elliptical ear opening (Fig. 3A), smooth dorsal scales on dorsum and tail lacking longitudinal ridges (Fig. 1A & B, Fig. 2A), scales on dorsal surface of fourth toe ar- ranged in multiple rows with oblique sutures with only the terminal 1–4 scales single, possessing transverse sutures, 24–31 subdigital lamellae under fourth toe that are grooved and bluntly callused, 10–13 plantar scales from heel to base of third toe and dark brownish-black calli on scales of palmar and plantar surfaces (Fig. 3D); background colour of dorsum and tail rich rusty red in live specimens, 17–24 narrow irregular dark bands on nape and dorsum that are at most a single scale wide and > 40 transverse narrow dark bands on original tail (Figs. 1A & B, Fig. 2A, Fig. 4 in Mecke & Doughty 2018).|
Comparisons with other species. Based on specimen examination and data from the literature (storr et al. 1999; mecke et al. 2009, 2013), we compare E. rubigino sus with other banded taxa from Western Australia, with which the new taxon could be confused.
Eremiascincus rubiginosus can be distinguished from E. intermedius by scales covering fourth toe in multiple rows with oblique sutures, followed by 1 – 4 single ter- minal scales with transverse sutures (vs scales on top of fourth toe in multiple rows with oblique sutures followed by usually > 7 single scales with transverse sutures, sin- gle scales cover approximately a third of the length of the fourth toe); smooth dorsal surface of tail (vs dorsal surface of tail ridged); numerous (17 – 24) diffuse bands on nape and dorsum covering a single scale row at most, bands little contrasting with rusty red ground colour, sep- arated by an interspace of one or two scales only (vs 6 – 16 bands on dorsum, sharply defined, much more prominent, dark, and in strong contrast with the lighter, yellow to or- ange ground colour, separated by an interspace of three or four scales; cf Fig. 2A & B). Eremiascincus intermedius in Western Australia is confined to the Tanami Desert, and more widely distributed in the Northern Territory.
Eremiascincus rubiginosus can be distinguished from E. musivus by larger size in adults (59.7–81.5 mm vs 43.9 – 59.2 mm); snout rounded (vs depressed and point- ed; cf Fig. 3A & B); ear opening moderate and elliptical, with area of ear equalling area of eye (vs anterior mar- gin of ear oblique towards top, with ear opening much smaller than eye; cf Fig. 3A & B); paravertebral scales in 59–67 rows (vs paravertebral scales in 52–62 rows); lamellae under fourth toe in 24–31 rows, scales bluntly callused (vs lamellae under fourth toe in 18–26 rows, scales feebly keeled); pale vertebral line absent (vs pale vertebral line present); bands present on the dorsum (vs bands on the dorsum absent, dorsal pattern comprising pale and dark spots; cf Fig. 2A & B). Eremiascincus musivus is restricted to sandy habitats along the Pilbara coast, and more widely distributed in sandy regions out- side the Pilbara (Fig. 5).
Eremiascincus rubiginosus can be distinguished from E. pallidus by snout rounded (vs depressed and pointed; cf Fig. 3A & C); ear opening moderate and elliptical, with area of ear equalling area of eye (vs anterodorsal edge of ear opening with skin covering the opening extensively, with ear opening much smaller than eye; cf Fig. 3A & C); smooth dorsal surface of tail (vs dorsal surface of tail ridged); scales covering fourth toe in multiple rows with oblique sutures, followed by 1–4 single terminal scales with transverse sutures (vs scales on top of fourth toe covered by single scales with transverse sutures for entire length of digit); subdigital lamellae grooved and bluntly callused (vs subdigital lamellae not grooved and only feebly keeled or callused); plantar scales 10–13, ovate and capped with dark calli (vs plantar scales 14 – 18, acute, without calli; cf Fig. 3D & E); bands present on the dorsum (vs bands on the dorsum almost always ab- sent in adults, at most faint bands on side of body, pale; cf Fig. 2A & D, Fig. 4). Juveniles of E. pallidus may ex- hibit bands on the dorsum, which fade with growth (Fig. 4B). Eremiascincus pallidus, throughout its entire range, is found in sandy habitats only and is absent from the rocky, more elevated parts of the Pilbara (Fig. 5).
Eremiascincus rubiginosus can be distinguished from E. richardsonii by typically seven supralabials (vs usu- ally eight supralabials); three chin shields (vs usually four chin shields); smooth dorsal surface of tail (vs dor- sal surface of tail ridged); numerous (17 – 24) diffuse bands on nape and dorsum covering a single scale row at most, bands little contrasting with rusty red ground colour, separated by an interspace of one or two scales only (vs 7 – 14 bands on dorsum sharply defined, much more prominent, dark, and in strong contrast with the lighter, yellow to orange ground colour, separated by an interspace of three or four scales); > 40 narrow bands on tail (vs 19 – 32 usually broad bands on tail). Eremia scincus richardsonii in Western Australia favours heavy and stony soils and may be encountered in sympatry with E. rubiginosus. Characters distinguishing the banded species of Eremiascincus occuring in the Pilbara region are summarized in Table 2.
|Comment||Habitat: gorges, rocky gullies, riverbeds or caves surrounded by woodland. The species appears to be largely restricted to rocky habitats and may be encountered in leaf litter covering rock formations or under rock ledges.|
|Etymology||The specific name is based on the Latin adjective rubiginosus (rusty red).|