Carlia rubigo, Hoskin & Couper, 2012

Hoskin, Conrad J. & Couper, Patrick J., 2012, Description of two new Carlia species (Reptilia: Scincidae) from north-east Australia, elevation of Carlia pectoralis inconnexa Ingram & Covacevich 1989 to full species status, and redescription of Carlia pectoralis (de Vis 1884), Zootaxa 3546, pp. 1-28 : 11-14

Carlia rubigo sp. nov.

Orange-flanked Rainbow Skink

( Figs 1A & B, 2 BN, 3B, 4B, 5B, 6B, 7B, 8B, 9B, 10D)

Holotype. QMJ90885, male, Magnetic Island, Gustav Ck (19°08'50"S, 146°50'41"E), north-east Queensland, C. Hoskin, 13 February 2011.

Paratypes. QMJ78516-17 Survey Dam , Princess Hills, Girringun NP (18°14' 14"S, 145°28' 34"E) ; J90883 -84 Magnetic Island , Gustav Ck (19°08'50"S, 146°50'41"E) ; J76655 , J76658 -59 Nelly Bay , Magnetic Is (19°10'S, 146° 51'E) ; J90890 Cape Cleveland (19°17'29"S, 147°01'22"E) ; J65166 Shark Bay , Cape Upstart (19°44'S, 147°45'E) ; J65165 Cape Upstart , on top (19°44'S, 147°49'E) ; J90886 -87 Lolworth Ck , near Dalrymple National Park (19°51'37"S, 146°07'45"E) ; J75179 Gloucester Island (20°02' 30"S, 148°26' 30"E) ; J89141 -42 , J89145 -47 Airlie Beach , Shute Harbour Rd, Mandalay (20°17'S, 148°44' 21"E) ; J83256 Clermont , 6.5 km NNW (22°46' 06"S, 147° 37' 39"E) ; J83279 Scotts Peak , Feez Creek Stn (22°51' 44"S, 148°13' 31"E) ; J88423 Valencia Station (22°56' 14"S, 147°46' 18"E) .

Additional material. J60245 , J60253 Mt Mulligan (16°48' 56"S, 144°46' 12"E) ; J75125 Forty Mile Scrub, 2.1 km S of park boundary (18°07' 58"S, 144°48' 50"E) ; J74273 Princess Hills, Girringun NP (18°19' 23"S, 145°22' 41"E) ; J74780 Shaft Cave , Fanning Caves (19°48'S, 146°28'E) ; J85004 , J85006 Rochford Scrub (20°07' 05"S, 146°37' 43"E) ; J89148 Airlie Beach, Shute Harbour Rd, Mandalay (20°17'S, 148°44' 21"E) ; J44438 , J44457 , J44787 Warrawee Stn , 60km SE Charters Towers (20°20'S, 146°39'E) ; J44696 -98 St Pauls Stn (20°24'S, 146°58'E) ; J44707 -08 Mt Cooper Stn (20°30'S, 146°51'E) ; J44626 Natal Downs Stn (21°05'S, 146°10'E) ; J77971 Newlands Coal Mine (21°13'S, 147°53'E) ; J82977 Lord's Table summit (22°39' 17"S, 148°00' 55"E) ; J78677 Nairana NP (21°43' 28"S, 146°53' 31"E) ; J82997 , J83006 Coomburragee Stn, nr (22°53' 59"S, 148°20' 04"E) ; J76759 Cudmore NP (22°56' 23"S, 146°17' 43"E) ; J76866 SF161 Condamine, 5.5km SE of Wilgo Downs Stn (26°57' 06"S, 150°15' 14"E) ; J78641 Yalebone Ck. 6km W Newington hstd, NW Surat (27°07' 22"S, 148°57' 47"E) ; J80137 Warrego Highway Stock Route, 27km W of Mitchell (26°28' 23"S, 147°39' 46"E) .

Diagnosis. A moderate sized Carlia (max SVL 44 mm) that can be distinguished from all its congeners by a combined suite of characters. Interparietal scale free. Dorsal scales tricarinate and hexagonally-shaped. Palpebral disc large. Ear aperture round to vertically elliptic with one or two rounded lobules on the anterior margin and sometimes with smaller, rounded lobules on other margins ( Fig. 8B). Supraciliaries usually five. Prefrontals usually narrowly separated or in point contact ( Fig. 9B). Upper preocular minute or a narrow, vertical sliver ( Fig. 10D). Breeding male with pale blue throat and broad orange or coppery flush on flanks; black speckling present on neck and jawline but no heavy black edging to scales on throat ( Figs 1C, 2B, 4B, 5B). Adult female with a white mid-lateral stripe that usually breaks up posteriorly into white flecks ( Figs 1D, 6B). Both sexes have a pale greyish tinge on the ventral surface.

Etymology. From the Latin rubigo , meaning ‘rust'. In reference to the rusty orange colouration on this species, particularly on the flanks of males. The species epithet is treated as a noun in apposition.

Description of holotype ( Fig. 7B). QMJ90885, male. Measurements (mm): SVL 39.3; tail (damaged); interlimb 18.7; HLL 20.1; TL 6.2; HW 6.7; HL 9.1. Scalation: Dorsal scale keels 3; midbody scale rows 30; paravertebrals 47; supralabials 7; infralabials 6; supraciliaries 5, subdigital lamellae (4 th toe) 28; subdigital lamellae (3 rd finger) 21. Upper preocular reduced to a narrow vertical sliver, well separated from posterior edge of 2 nd loreal scale; palpebral disc large; ear <palpebral disc, vertically elliptic with one large rounded lobule on anterior margin; postsupralabial divided; nasals widely spaced; prefrontals very narrowly separated, almost in point contact.

Colour pattern of holotype in preservative. Dorsal surfaces brown, faint indication of some darker and lighter markings. Lateral surfaces flushed with a coppery and greenish colouration. Iridescent sheen to scales. Neck and jawline pale blue, with black flecking to scales forming thin longitudinal rows. Throat pale with a blue tinge, some dark flecks towards sides of neck and jawline. Pale markings from nare, under eye, and to tympanum. Ventral surfaces creamy white. Prominent white spot at posterior base of hindlimb. Tail greyish brown with dark and light markings.

Description of type series. Body robust with keeled dorsal scales. Head barely distinct from neck. Snout rounded in profile. Limbs moderate; four fingers; five toes. Adult measurements and proportions: see Table 1. Scalation: Rostral in broad contact with frontonasal. Postsupralabial divided. Nasals widely spaced. Prefrontals large and usually narrowly separated (narrow separation 77%, moderate separation 19%, contacting 4%) ( Fig. 9B). Supraoculars 4, 1 and 2 in contact with frontal, 2, 3 and 4 in contact with frontoparietal. Frontoparietals fused, forming a single shield. Interparietal distinct. Enlarged nuchal scales 2. Loreals 2. Preoculars 2. Upper preocular very small, either a narrow vertical sliver (70%) or minute (30%) ( Fig. 10D). Presubocular single. Supraciliaries 5, very rarely 4 or 6. Lower eyelid movable with clear window; palpebral disc large, occupying more than half of lower eyelid. Ear aperture smaller than palpebral disc. Ear opening vertically elliptic (86%) or round (14%), with a rounded lobule present on anterior margin ( Fig. 8B); additionally often also small, low lobules present on the other margins of the ear (48% of specimens). Supralabials 7, with the fifth below the eye. Infralabials 6. Three scales between the nasal scale and the presubocular. Midbody scale rows 30–32 (mean = 31); dorsal scales with tricarinate keels (very rarely 2). Paravertebral scale rows 45–48 (mean = 47). Subdigital lamellae under 3 rd finger 17–21 (mean = 19). Subdigital lamellae under 4 th toe 23–29 (mean = 27).

Colour pattern in preservative. Males ( Figs 3B, 4B, 5B, 7B): dorsal surfaces rusty brown, generally with black and white dots on the back half of the dorsum and continuing along the tail. Top of head generally lighter brown; often with fine black dots. Lateral surfaces washed with orange or copper colouration, sometimes with a greenish tinge. Iridescent sheen to scales. Neck, throat and jawline pale blue or white. Black speckling and edging to scales of sides of neck and jawline, generally forming fine longitudinal rows. Usually no dark markings on throat. Often white line or markings from nare to beneath eye. Ventral surfaces cream-grey or cream. Prominent white spot at posterior base of hindlimb. Tail brown with black and white flecks. Females ( Fig. 6B) dorsal surfaces brown, often rusty towards the anterior half and flecked or spotted with black and white towards the posterior half and tail. Top of head generally lighter brown; often with fine black dots. Thin white line from snout, under eye, through tympanum, and extending as a mid-lateral line to above forelimbs or mid flank before breaking up into white flecks or an indistinct ragged line. In a few specimens white mid-lateral line extends to groin. Flanks brown or grey and heavily flecked with white; upper flanks sometimes tawny brown. Ventral surfaces grey tinged or creamy grey. White spot at posterior base of hindlimb. Tail brown with black and white flecks.

Colour pattern in life ( Figs 1C, 1D, 2B). Dorsum of both sexes coppery brown with black and white paravertebral dots or flecks on posterior half. Ventral surfaces greyish white. Breeding males with pale blue throats and black speckling on jawline and neck. The throat is generally clean but grey or black speckling sometimes extends onto the throat. Speckling of the neck and throat is sometimes arranged coarsely as thin transverse lines. A broad coppery/orange flush extends from forelimb along flank. At maximum breeding extent orange can extend onto the back and forelimbs, and blue can extend over entire head. Parts of the flanks and head can sometimes have a greenish tinge. Adult females have a white mid-lateral stripe that extends from nostril to forelimb or mid flank, before breaking up into a series of pale flecks.

Comparison. Only likely to be confused with C. decora sp. nov., C. pectoralis and C. inconnexa . Carlia rubigo sp. nov. is readily distinguished from C. inconnexa by tricarinate versus mixed bicarinate/tricarinate middorsal scales, smaller size, lower midbody, paravertebral and lamellae scale counts, and colour pattern (see C. inconnexa Comparison section; Table 1). From C. decora sp. nov. and C. pectoralis , C. rubigo sp. nov. is distinguished most easily by breeding male colouration ( Figs 1–5). The flanks of male C. rubigo sp. nov. are broadly flushed with orange or copper colouration whereas orange is confined to upper and lower lateral lines on the flanks of male C. decora sp. nov. and C. pectoralis . The orange on the flanks of C. rubigo sp. nov. is sometimes concentrated towards the upper and lower flanks but it is nonetheless suffused over the entire flank to some extent. Breeding male C. rubigo sp. nov. are further distinguished from male C. pectoralis by the lack of heavy black edging (scalloping) on the scales of the throat. Female C. rubigo sp. nov. and C. pectoralis are of similar pattern but C. decora sp. nov. females have a bold white mid-lateral line that always extends to the groin (vs. less distinct white line that generally breaks up to white speckles on posterior flank in C. rubigo sp. nov. and C. pectoralis ) ( Figs 1, 6). Carlia rubigo sp. nov. is further distinguished from C. decora sp. nov. by higher midbody scale count (30 or more vs. 30 or less), generally smaller body size (75% of C. rubigo sp. nov. specimens measured <42 mm vs. 75% of C. decora sp. nov. > 42 mm), upper preocular minute or a narrow vertical sliver (vs. broadly triangular) and prefrontal spacing generally narrow or very narrow (vs. moderate) ( Table 1; Figs 9, 10). Carlia rubigo sp. nov. is further distinguished from C. pectoralis by usually having a vertically elliptical ear opening (vs. round), with one low, rounded anterior lobule and sometimes also low lobules on other margins (vs. more prominent rounded or bluntly pointed lobules on all margins) ( Fig. 8). Carlia rubigo sp. nov. also tends to have more subdigital lamellae under the 4 th toe (mean: 27 vs. 25; 75% of C. rubigo sp. nov. specimens examined have 26 or more, 75% of C. pectoralis have 26 or fewer) ( Table 1).

Genetics. Carlia rubigo sp. nov. is approximately 10% divergent (ND4 mtDNA) from C. inconnexa and C. pectoralis and approximately 16% divergent from Carlia decora sp. nov. (C. Hoskin, unpublished data). A representative ND4 mtDNA sequence for this species from the type locality is JX291973 (GenBank accession number).

Distribution. Carlia rubigo sp. nov. is found in inland eastern Queensland, from close to the New South Wales border in the south (Texas, St George areas), to west of Cairns in the north, and throughout central eastern Queensland including coastal areas between approximately Mackay and Townsville and on associated offshore islands (e.g. Magnetic Island, Gloucester Island) ( Fig. 11).

Habitat and habits. Carlia rubigo sp. nov. is found in dry open forests, grasslands and rocky habitats, particularly in areas with a complex ground cover of grass tussocks, leaf litter and rocks ( Fig. 12B). It is an active, ground-dwelling skink.