Carlia inconnexa Ingram & Covacevich 1989

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 : 17-24

Carlia inconnexa Ingram & Covacevich 1989

Whitsunday Rainbow Skink

( Figs 1H, 2D, 3D, 4D, 5D, 6D, 7D, 8D, 9D, 10F)

1989 Carlia pectoralis inconnexa Ingram & Covacevich. Memoirs of the Queensland Museum 27(2): 468. Hayman Island , Queensland. Holotype AM R 47178.

Holotype. AM R 47178, male, Hayman Island (20°03'S, 148°53'E).

Paratypes. J25060 Hayman Is (20°03'S, 148°53'E) ; J42496 Whitsunday Is (20°15'S, 149°00'E) .

Additional material. J48093 -95 Hook Is, Nara Inlet (20°07' 30"S, 148°55' 30"E) ; J75251 , Whitsunday Is (20°15' 30"S, 148°56' 30"E) ; J86535 , J86539 Whitsunday Is (20°17' 46"S, 149°03' 13"E) ; J86538 , Whitsunday Is (20°17' 46"S, 149°03' 14"E) ; J86549 , Whitsunday Is (20°17' 46"S, 149°03' 22"E) ; J89132 , J89134 -35 , J89138 Whitehaven Whitsunday Is (20°17' 47"S, 149°03' 13"E) .

Diagnosis. A large, robust Carlia (max SVL 52 mm) that can be distinguished from all its congeners by a combined suite of characters. Interparietal scale free. Dorsal scales predominantly bicarinate (but often include a mix of both bicarinate and tricarinate scales) and hexagonally-shaped. Palpebral disc large. Ear vertically elliptic or round, with one or two rounded lobules on the anterior margin ( Fig. 8D). Supraciliaries usually five. Prefrontals narrowly separated ( Fig. 9D). Upper preocular a narrow, vertical sliver ( Fig. 10F). Breeding male with a black head, throat and neck ( Figs 1G, 2D, 3D, 4D, 5D). Both sexes grey or brown and heavily mottled with black and white markings that are aligned in longitudinal rows ( Figs 1–6).

Etymology. Formerly the subspecies name for these populations. Derived from Latin and meaning ‘unjoined'; in reference to the fact the species is found on offshore islands ( Ingram & Covacevich 1989). The species epithet is treated as a noun in apposition.

Description of holotype ( Fig. 7D). R47178, male. Measurements (mm): SVL 51.7; tail 98.5 interlimb 22.8; HLL 27.2; TL 8.8; HW 9.0; HL 12.1. Scalation: dorsal scales with a mix of 2 or 3 keels (i.e. bicarinate/tricarinate); midbody scale rows 34; paravertebrals 49; supralabials 7; infralabials 6; supraciliaries 5, subdigital lamellae (4 th toe) 27; subdigital lamellae (3 rd finger) 20. Upper preocular reduced to a narrow vertical sliver, well separated from posterior edge of 2 nd loreal scale; palpebral disc large; ear aperture <palpebral disc size; ear opening round to vertically elliptic with one large rounded lobule on anterior edge and smaller rounded lobules on other margins; postsupralabial divided; nasals widely spaced; prefrontals narrowly separated.

Colour pattern of holotype in preservative. Dorsum light brown with approximately 10 thin, black longitudinal lines. Top of head light brown with fine black dots. Lateral surfaces light brown with some indication of fine darker markings longitudinally. Sides of neck and jawline smudged dark grey, with heavy black edging to scales. Ventral surfaces creamy yellow. Dorsal surfaces of limbs light brown, flecked with darker markings; undersides creamy yellow. Tail creamy brown.

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, usually narrowly separated (narrow separation 87%, moderate separation 13%) ( Fig. 9D). 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, generally a narrow vertical sliver or sometimes a minute granule ( Fig. 10F). Presubocular single. Supraciliaries 5 (66%) or 6 (33%). 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 with one (44%) or two (56%) rounded lobules on the anterior margin ( Fig. 8D). Supralabials 7 (89%) or 8 (11%), with the fifth below the eye. Infralabials 6 (85%) or 7 (15%). Three scales between the nasal scale and the presubocular. Midbody scale rows 32–34 (mean = 34). Dorsal midbody scales predominantly with bicarinate keels, but usually a mix of scales with bicarinate and tricarinate scales. Paravertebral scale rows 49–53 (mean = 51). Forelimb tetradactyl, with 21–23 (mean = 22) lamellae beneath 3rd finger. Hindlimb pentadactyl, with 27–31 (mean = 29) lamellae beneath 4 th toe.

Colour pattern in preservative. Males ( Figs 3D, 4D, 5D, 7D): dorsal and lateral surfaces have a mottled grey, black and white appearance. Dorsum grey with an obvious paravertebral pair of black blotches interspersed with white flecks; more rarely, fine black dorsal stripes on a more even brown background. Scales iridescent. Top of head black or brown. Flanks grey and heavily mottled with black smudges and white flecks. Flanks of some individuals have a soft orange, copper or greenish wash. Sides of head, neck and throat either completely black or heavily smudged or mottled with black or bluish black. Top of limbs mottled grey, black and white; undersides pale. Ventral surfaces cream or grey. Tail brown or grey, with heavy black and white blotching and flecking. Females ( Fig. 6D): dorsal and lateral surfaces have a mottled brown, grey, black and white appearance. Dorsum brown or grey with an obvious paravertebral pair of black blotches interspersed with white flecks. Scales iridescent. Top of head brown or copper. Flanks heavily mottled brown, grey, black and white. Generally a row of black blotches along the upper flank. Thin white line from nare to tympanum, then extending as an indistinct ragged, mottled or flecked white line along at least the anterior portion of the flank. Top of limbs mottled grey, black and white; undersides pale. Ventral surfaces grey or cream. Tail brown or grey, with heavy black and white blotching and flecking.

Colour pattern in life ( Fig. 1H). Both sexes grey or brownish and heavily blotched and flecked with black and white markings. Dorsum variable: usually a pair of paravertebral stripes consisting of black blotches and white flecks, or, more rarely, fine black dorsal stripes on a more even brown background. Flanks heavily blotched and flecked with black and white, particularly on the upper flanks. Adult females have an obscure, ragged, narrow, whitish mid-lateral stripe. Ventral surfaces greyish white. Colouration in life of breeding males is not known but the following can be interpreted from preserved specimens in breeding colour ( Figs 1–5). The throat, head and neck are black. At maximum breeding extent the entire head of males is black. Some males in preservative have a copper wash to the flanks. Based on comparisons with males of other Carlia species covered herein that were examined in life then subsequently after preservation, it is unlikely that male C. inconnexa have bright orange lateral lines in life (as for C. decora sp. nov. and C. pectoralis ). Rather, it is likely they have an orange/copper wash to the flanks when breeding.

Comparison. Carlia inconnexa is a highly distinct species that is readily distinguished from all congeners. The only species it is likely to be confused with are C. vivax , C. decora sp. nov., C. rubigo sp. nov., C. pectoralis . The similarity to C. vivax is that C. inconnexa has predominately bicarinate mid-dorsal scales; however, the two species are otherwise easily distinguished. Carlia inconnexa is larger (SVL 46–53 mm vs. <47 mm) and more robust, has higher counts on several scale traits (e.g. mid body scale rows, mean 34 vs. mean 30; lamellae under 4 th toe, mean 29 vs. mean 25) and male and female C. inconnexa are grey or brown with black and white mottling (vs. C. vivax not mottled). From C. decora sp. nov., C. rubigo sp. nov. and C. pectoralis , C. inconnexa can be distinguished by larger size (mean SVL 50 mm vs. means of less than 45 mm for the other species), more midbody scales (32–34 vs. 32 or less), more paravertebral scales (mean 51 vs. means 47), generally higher counts for lamellae under the 4 th toe and 3 rd finger, heavily mottled colouration of males and females, and black head of breeding males ( Table 1; Figs 1–6). Carlia inconnexa superficially resembles Liburnascinscus mundivensis (Broom) , which is also a robust, grey or brown, blotched, rock-dwelling species (but is not known to occur on the Whitsunday Islands). The two species are readily distinguished by predominately bicarinate dorsal scales on C. inconnexa (vs. predominately tricarinate in L. mundivensis ), fewer supraciliaries in C. inconnexa (generally 5 vs. 7), ear opening of C. inconnexa vertically elliptical with 1–2 rounded, anterior lobules (vs. round ear opening surrounded by many acute lobules) and fewer midbody scale rows for C. inconnexa (32–34 vs. 34–42).

Genetics. Carlia inconnexa is approximately 10% divergent (ND4 mtDNA) from C. rubigo sp. nov. 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 Whitsunday Island is JX291974 (GenBank accession number).

Distribution. Carlia inconnexa is found on islands of ‘the Whitsundays’ off mid-eastern Queensland ( Fig. 11). It is known from Whitsunday, Hook and Hayman islands of the Whitsunday Group, and Lindeman Island (Lindeman Group). All these islands are part of the Cumberland Islands.

Habitat and habits. Carlia inconnexa is found in rocky forests and scrubs ( Fig. 12D). It appears to be primarily saxicoline.

Remarks. Ingram & Covacevich (1989) described inconnexa as a subspecies of C. pectoralis based on bicarinate (versus tricarinate) dorsal sclaes and dark lines on the dorsum of males. We have elevated inconnexa to species status due to substantial further differences from C. pectoralis , C. rubigo sp. nov. and C. decora sp. nov.. Carlia inconnexa is a considerably larger skink and has more paravertebral and midbody scales than the other species, and generally has more subdigital lamellae under the 3 rd finger and 4 th toe. It also differs subtantially in colour pattern compared to the other species. Both sexes of C. inconnexa are usually heavily mottled with black and white and the breeding colour of males at maximum extent is unique in that the head, throat and neck are black.

We regard the photo of a male C. inconnexa in Wilson & Swan (2010) as dubious. The individual is not heavily mottled and, although in breeding colours, it lacks any black on its head. The bright orange upper and lower lateral lines are also atypical compared to the colour pattern evident on the male C. inconnexa specimens we examined (generally a faint copper wash to the flanks). The colour pattern of the male in this photo is generally consistent with that of C. decora sp. nov., a species that also occurs on Whitsunday Island. We are not aware of any photo in life of a male C. inconnexa . Photos of males in life are required.