Cyrtodactylus pronarus, Shea & Couper & Wilmer & Amey, 2011

Shea, Glenn, Couper, Patrick, Wilmer, Jessica Worthington & Amey, Andrew, 2011, Revision of the genus Cyrtodactylus Gray, 1827 (Squamata: Gekkonidae) in Australia 3146, Zootaxa 3146 (1), pp. 1-63 : 51-56

Cyrtodactylus pronarus sp. nov.

( Figs. 26–27 )

Holotype. QM J86900 , female, Peach Creek , 535 m asl, McIlwraith Range (13º 45' 22" S 143º 19' 59" E) (P. Couper, A. Amey, R. Howard, G. Kyle, F. Port & T. Creek, 12.ix.2009).

Paratypes. QM J38197 –98 , J60863 –66 , J60868 , Peach Creek , McIlwraith Range (13º 45' S 143º 19' E) ; J86899 , J86909 –10 , J86922 –23, Peach Creek , McIlwraith Range (13º 45' 22" S 143º 19' 59" E) ; J38330 –31, Lankelly Creek , McIlwraith Range (13º 53' S 143º 14' E) ; J60320 , Klondyke Mine , McIlwraith Ranges (13º 57' S 143º 19' E) .

Diagnosis. A large Cyrtodactylus (SVL to 132.5 mm) with enlarged tubercles on antebrachium absent, moderately-developed dorsal tubercles in 20–24 longitudinal rows at the midpoint of the trunk (axilla-groin interval); 35–45 ventral scale rows at the same level, a continuous series of 58–66 enlarged femoroprecloacal scales extending from one knee to the other, each scale bearing a pore in males; mental bordered posteriorly by a small median scale (replacing the tip of the median posterior extension of the mental), and a pair of postmentals; lips pale, strongly contrasting with the brown upper face; dark dorsal bands on trunk three, with a narrow dark edge posteriorly but the anterior margin blending with the pale interspace; pale interspaces between dark body bands lacking blotches or spots; basal tail bands more than twice as wide as pale interspaces.

Description. Size large (males 104.5–126.5 mm, mean = 119.7, sd = 7.50, n = 11; females 113–132.5 mm, mean = 125.7, sd = 9.04, n = 4).

Head relatively long (HL/SVL 27.8–30.2%, mean = 28.8; sd = 0.66, n = 16) and wide (HW/HL 64.7–75.2%, mean = 68.9%; sd = 2.59, n = 16), moderately depressed (HD/HL 34.4–40.0%, mean = 37.8%, sd = 1.73, n = 16), distinct from neck. Loreal region moderately inflated, canthus rostralis poorly defined. Interorbital region and top of snout concave, deepest and widest just anterior to level of rostral canthus of eye. Snout moderately long (SL/HL 37.7–40.9%, mean = 39.5, sd = 0.91, n = 16; EN/HL 28.2–32.1%, mean = 29.8, sd = 1.09, n = 16), much longer than eye diameter (SL/EYE 164.4–201.5%, mean = 184.6%, sd = 11.26, n = 16), and a little longer than eye-ear interval (EE/HL 26.7–30.3%, mean = 28.7%, sd = 1.32, n = 16). Eye large (EYE/HL 19.2–24.6%, mean = 21.5%, sd = 1.43, n = 16), pupil vertical with crenated margin, forming about 3–4 low lobes along each edge of pupil. Supraciliaries in a double row, large, frill-like, well-differentiated from adjacent, more medial granules of the brow ridge, and largest anteriorly. Ear opening small (EAR/HL 5.7–8.8%, mean = 7.0%, sd = 0.99, n = 16), usually a little taller than long and slightly angled posterodorsally, but sometimes rounder. Rostral wider than high, height at centre less than that more laterally, dorsal part divided by a median groove that extends about 1/6–⅔ the midline height of the scale, and fails to reach the oral margin; in 63% of specimens the median groove terminates in a small, circular scale isolated within the rostral shield (in QM J60865 the median groove extends beyond the circular scale towards the oral margin of the shield). Two enlarged supranasals separated by 1–3 less enlarged internasals that contact the dorsal edge of the rostral shield (1 = 31%, 2 = 63%, 3 = 6%). External nares circular, bordered by first supralabial, rostral, supranasal, nasal (extending into posterior part of nostril) and 2–3 smaller granular scales between nasal and first supralabial. Nares moderately separated (IN/HL 11.2–12.4%, mean = 11.8%, sd = 0.35, n = 16). Supralabials anteriorly large, distinct from adjacent loreal granules, 10–12 (mode = 10 (56.3%), mean = 10.6, sd = 0.73., n = 16) to level of mid-orbit, then inflecting dorsally and posteriorly, and becoming smaller, to gradually blend along rictal margin with adjacent small granules; supralabials separated from orbital margin by at least four rows of small, granular scales at narrowest point. Mental wider than deep and a little to moderately narrower than rostral, bordered posteriorly by a single elongate pair of large postmentals. In 88% of specimens, these are separated anteriorly by a small to moderate, elongate scale that contacts the posterior edge of the mental ( Fig. 10E–F ); this scale may be derived from the fragmented median extension of the rostral. Infralabials anteriorly much larger than adjacent gular scales, becoming smaller posteriorly, 11–13 (mode = 12 (50.0%), mean = 11.8, sd = 0.68, n = 16). First infralabial with ventral border ¾ to fully contacting postmental; at most only in narrow contact with anteriormost enlarged subinfralabial. Subinfralabial scales anteriorly large, flattened and polygonal, becoming smaller, more rounded and granular posteriorly and medially (towards gular area).

Body moderately robust (AGL/SVL 41.0–47.0%, mean = 44.3%, sd = 1.47, n = 16), with low, but distinct, ventrolateral skin folds approximately marking the transition between the enlarged flattened ventral scalation and the smaller, more rounded, granular lateral scalation. Scales on dorsum of head, body and limbs small, juxtaposed, rounded granules, with interspersed much larger tubercles. Granular scales finest over parietal region of head, becoming coarser over body, then larger, flatter and more polygonal on tail. On head dorsum ( Fig. 11E ), tubercles small and only slightly projecting, anteriorly commencing in the posterior crown area, becoming larger, more projecting and with a more conical apex over nape. Tubercles on body dorsum larger again ( Fig. 12E ) with a more longitudinally ovoid base and a low, weak median keel. Tubercles slightly larger over sacrum and large and somewhat flattened on tail base. Tubercles persist along tail, becoming lower and less differentiated until eventually losing their distinction by about the third dark band. Large tubercles on body dorsum separated by 2–5 smaller, granular scales. Tubercles on body arranged in about 20–24 (mean = 22.0, sd = 1.15, n = 16) roughly longitudinal rows. Dorsum of brachium with uniform, slightly imbricate scalation, larger tubercles very sparse to entirely absent; antebrachium with more imbricate slightly larger scales distally and over manus ( Fig. 13E ). Dorsum of thigh and crus with small juxtaposed granules and numerous, low tubercles ( Fig. 13J ), only dorsum of pes with imbricate scales.

Laterally, tubercles commence over temporal region (a few may be present in the postinfralabial area) where they are low and rounded and only slightly larger ( Fig. 11J ) than those of the head dorsum, then along nape and body, where they are smaller and noticeably less protuberant than those dorsally, and along tail, commencing on tail base as low, posteriorly deflected, conical scales, then rapidly losing differentiation within the first dark tail band ( Fig. 14E ).

Ventrally, gular scales small, rounded and juxtaposed, becoming larger, flat and more imbricate over body venter, from clavicular region. Ventral scales at midbody, between ventrolateral skin folds 35–45 (mean = 40.0, sd = 2.63, n = 16). Ventral scales on brachium and antebrachium like gular scales. On ventral surface of thighs, but not on crus or in precloacal region, an abrupt junction between enlarged imbricate scales and much smaller scales posteriorly, enlarged scales 58–66 between distal extent on each thigh (mean = 62.1, sd = 2.54, n = 16). Ventral scales of tail base like those of body, most of tail venter with a single median series of very broad scales about four times the width of adjacent ventrolateral scales.

Precloacal and femoral pores present in males, in a single continuous row, arching shallowly anteriorly in precloacal region. Pores 58–66 (mean = 62.5, sd = 2.62, n = 11), best developed in precloacal region where they are deep and transversely oriented, becoming much shallower, smaller and rounder distally under thigh. No pubic groove. About three large, blunt-tipped postcloacal spurs on ventrolateral surface of tail base, more projecting in adult males than in females.

Forelimbs and hindlimbs well-developed (FLL/SVL 15.0–16.6%, mean = 16.0%, sd = 0.37, n = 16; HLL/SVL 18.2–20.6%, mean = 19.0%, sd = 0.60, n = 16). Digits well-developed, reflected dorsally at proximal interphalangeal joint, and all bearing robust, strongly curved claws sheathed at the base by two scales. Subdigital lamellae expanded basally, beginning on pes over distal part of metatarsals and ending at point of reflection of toes, lamellae distal to this point not expanded. Lamellae under first toe 8–9 expanded (mean = 8.4, sd = 0.51, mode = 8 (56.3%)) + 10–12 narrow (mean = 10.8, sd = 0.66, mode = 11 (56.3%)), total 18–20 (mean = 19.3, sd = 0.68, mode = 19 (50.0%), n = 16). Lamellae under second toe 8–11 expanded (mean = 10.2, sd = 0.83, mode = 10 (50.0%)) + 12–14 narrow (mean = 12.6, sd = 0.63, mode = 12 (50.0%)), total 22–24 (mean = 22.8, sd = 0.68, mode = 23 (50.0%), n = 16). Lamellae under third toe 9–12 expanded (mean = 10.9, sd = 1.26, mode = 12 (50.0%)) + 13–16 narrow (mean = 14.0, sd = 0.97, mode = 13 (37.5%)), total 23–27 (mean = 24.9, sd = 1.09, mode = 25 (43.8%), n = 16). Lamellae under fourth toe 11–15 expanded (mean = 13.4, sd = 1.03, mode = 13 (37.5%)) + 12–16 narrow (mean = 14.3, sd = 1.35, mode = 15 (37.5%)), total 26–30 (mean = 27.8, sd = 1.18, mode = 28 (37.5%), n = 16). Lamellae under fifth toe 8–11 expanded (mean = 9.9, sd = 1.06, mode = 11 (37.5%)) + 13-19 narrow (mean = 14.7, sd = 1.82, modes 13, 15 (37.5%)), total 23–28 (mean = 24.6, sd = 1.31, mode = 24 (43.8%), n = 16). Relative lengths of digits on manus I<II<V<III<IV; on pes I<II<III=V<IV. Very slight traces of webbing between bases of fingers; weak webbing between bases of toes 2–3 and 3–4.

Tail a little longer than body (TL/SVL 130.5–132.7%, n = 2), narrow at base (TW/SVL 6.2–10.4%, mean = 7.4%, sd = 1.15, n = 16) and tapering evenly to a conical tip. Tail segments externally identifiable by straight scale junctions, segments about 7–9 scales long basally when counted to include tubercles. Cloacal sacs present in both sexes, larger in males, external orifices just posterior to vent, laterally.

Colour in preservative. Dorsal pale ground colour fawn. Head dorsum ( Fig. 11E ) somewhat darker but relatively unmarked, bordered posterolaterally by a narrow pale band. Pale nape zone bordered posteriorly by a Ushaped dark chocolate-coloured chevron on nape, widest vertebrally, and extending anteriorly over temporal region to eye, then visible as a narrowing, increasingly diffuse streak over the lores to the nostril; chevron deepest along vertebral region and with a small U-shaped dip on posterior midline. Second broad dark transverse dorsal band over shoulders, lateral margins extending anteroventrally in front of forelimbs. Three dark bands over trunk, extending lateroventrally with even width, but dissipating over flanks. One dark band over hips. Tail with dark bands over most of length, but these become increasingly diffuse near tip. When they can be counted to the distal end of tail, dark tail bands 11 (n = 2). On nape and body, the dark bands are markedly broader than the pale interspaces, and the posterior margin is strongly edged with darker pigment; each dark band fades progressively, often producing a water colour-like effect before merging with its anterior pale band. Dark tail bands ( Fig. 14E ) prominent chocolate brown and of similar width to body bands but much more distinct; more than twice as wide as pale interspaces. Pale interspaces of body unmarked.

Upper and lower lips ( Fig. 11J ) pale and unmottled. Dorsum of forelimbs and hindlimbs pale to mid brown, unpatterned.

Ventral surface of body cream but sometimes with diffuse brown pigment on abdomen. Ventral surface of tail generally dark but marked by pale blotches.

Description of holotype. The holotype of C. pronarus is a mature-sized male, with the following character states of those variable for the taxon: SVL 113 mm, AGL 51 mm, TL 150 mm, TW 7.1 mm, HL 32.3 mm, HW 21.8 mm, HD 11.1 mm, IN 4.0 mm, SL 12.8 mm, EN 9.7 mm, EYE 6.7 mm, EE 8.9 mm, EAR 2.1 mm, FLL 17.0 mm, HLL 21.0 mm, lamellae below digits I–V 9+11, 10+13, 12+15, 14+15, 10+15 respectively, supralabials 10, infralabials 12, rows of dorsal tubercles 22, transventral rows 43, femoroprecloacal scales 62, and dark tail bands 11.

Etymology. From the Greek πρó (pro = before) and ναρóς (naros = flowing), alluding to the blending of the anterior edge of the dark body bands with the preceding pale interspaces.

Distribution. Known only from a small area of the McIlwraith Range, north-east of Coen, Queensland ( Fig. 21 ). The three localities are within 22 km of each other, and all are at about 500 m asl. It is possible that the species occurs at higher elevations — the known localities represent accessible high points in the McIlwraith Range.

Conservation status. This species has a small known distribution that is unlikely to be much more extensive. We have no clear understanding of population size and under IUCN criteria regard it as Data Deficient. The large adult size and colourful pattern of this species may make it desirable for the illegal pet trade but it occurs in a remote, protected area that is largely inaccessible.

Comparison with other species ( Table 6). Cyrtodactylus pronarus is morphologically and genetically most similar to C. adorus , differing from it genetically by 8.53% sequence divergence on average ( Table 2). It is slightly larger than C. adorus (SVL males 104.5–126 mm vs 91.5–119 mm, females 113–132.7 mm vs 90.9–123 mm), has more numerous labial scales (supralabial modes 10 vs 9; infralabials 11–13 vs 10–11), the antebrachium lacks tubercles (small tubercles present in C. adorus ); the dark nape band lacks an anterior vertebral extension (present in C. adorus ); the dark body bands lack a sharply defined anterior edge, instead blending into the pale bands (sharply defined anterior and posterior margins to dark body bands in C. adorus ), and the dark bands on the tail are much wider than the pale interspaces (pale tail bands about a third the width of the dark bands, while those of C. adorus are about half the width of the dark bands). The two species are at present geographically separated by 135 km, but the intervening ranges (northern McIlwraith Range, Table Range, Macrossan Range) and rock outcrops have been poorly surveyed for nocturnal reptiles.

Cyrtodactylus pronarus is more genetically distinct from C. tuberculatus , C. mcdonaldi and C. hoskini , with average sequence divergences between 16.72% and 17.72% ( Table 2). Morphologically, it differs from C. tuberculatus , C. mcdonaldi and C. hoskini in having many more femoroprecloacal pores and enlarged femoroprecloacal scales (58–66 vs 48 or fewer for both characters). The hindlimbs are immaculate (vs mottled), the caudal dark bands are solid black (vs dark-edged with paler centres) and are much wider than the pale interspaces at the tail base (vs subequal width), and the lips are pale and immaculate, sharply contrasting with the brown face. In comparison to all three species, C. pronarus has much less developed tubercles, those that are present being smaller and less projecting than the other species, and the tubercles are greatly reduced on the tail, ceasing prior to the distal end of the first dark caudal band. In comparison to C. mcdonaldi , C. pronarus also has a continuous row of femoroprecloacal pores in males (vs broken into three segments). Cyrtodactylus pronarus also lacks vertebral extensions to the dark nape and body bands (present in C. hoskini ), and has the anterior margins of the dark body bands diffusing into the pale interspaces (vs with dark anterior margins in C. tuberculatus and C. hoskini ). It is also much larger than C. hoskini and C. mcdonaldi (SVL up to 133 mm vs 112 and 105 mm respectively) and a little larger than C. tuberculatus (maximum 120 mm).

It further differs from all other Australian Cyrtodactylus in usually having a small median scale ( Fig. 10 ; probably a fragmented posterior portion of the mental) anteriorly separating the first pair of postmentals (a feature otherwise only seen in one individual of C. adorus ).

In comparison to C. robustus , C. pronarus is smaller (maximum SVL 132 vs 161 mm), has lesser development of dorsal tubercles, has pale lips (vs mottled lips), the anterior margins of the dark body bands blend with the pale bands (vs anterior margins strongly defined by narrow dark then light band), lacks dark speckling on the venter and orange oral and cloacal mucosa, and has fewer dorsal tubercle rows (20–24 vs 24–30), femoroprecloacal pores and enlarged femoroprecloacal scales (58–66 vs 75 or more for both characters), and a generally narrower head (HW/ HL 65–75%, mean = 69% vs 69–84%, mean = 77%).

In comparison to C. klugei , C. pronarus has more dark body bands over the trunk (three vs usually two), pale lips (vs brown posterior supralabials), anterior margins of dark body bands poorly defined (vs sharply defined), fewer transventral scales (35–45 vs 43–49), and fewer femoroprecloacal pores (58–66 vs 66–76) and enlarged femoroprecloacal scales (58–66 vs 69–77)

Natural history. Specimens collected at Peach Creek were living amongst large granite boulders along a drainage line in well-developed rainforest ( Fig. 28 ). Cyrtodactylus have also been seen in similar habitat at Birthday Mountain. These are presumably also C. pronarus because of the close proximity of this locality to the McIlwraith Range.

Stomach contents of six individuals were reported by Covacevich et al. (1996; as Cyrtodactylus louisiadensis ). Ten food items were reported: an unidentified centipede (Chilopoda), the spider Heteropoda jugulans (Heteropodidae) , the scorpion Lychas sp. (Buthidae) , unidentified moth (Lepidoptera), unidentified wasp ( Vespidae ), unidentified cricket ( Gryllidae ), and four roaches (two Laxta sp. , two large Calolampra sp. , Blaberidae ).

Figures

FIGURE 10. Chin shields of Australian Cyrtodactylus species. A. C. tuberculatus (QM J87009), B. C. mcdonaldi (QM J87075), C. C. hoskini (QM J86950), D. C. adorus (QM J86979), E. C. pronarus (QM J86900), F. C. pronarus (QM J86909).

FIGURE 11. Dorsal (A-E) and lateral (F-J) aspects of head of Australian Cyrtodactylus species. A,F. C. tuberculatus (QM J87009), B,G. C. mcdonaldi (QM J30062), C,H. C. hoskini (QM J86950), D, I. C. adorus (QM J86979), E,J. C. pronarus (QM J86900).

FIGURE 12. Dorsal aspect of trunk of Australian Cyrtodactylus species. A. C. tuberculatus (QM J87189), B. C. mcdonaldi (QM J87075), C. C. hoskini (QM J86950), D. C. adorus (QM J86979), E. C. pronarus (QM J86909).

FIGURE 13. Tubercles on front (A-E) and hind (F-J) limbs of Australian Cyrtodactylus species. A,F. C. tuberculatus (QM J87189), B,G. C. mcdonaldi (QM J87075), C,H. C. hoskini (QM J86950), D,I. C. adorus (QM J86979), E,J. C. pronarus (QM J86900).

FIGURE 14. Tubercles and colour pattern on tail base dorsum of Australian Cyrtodactylus species. A. C. tuberculatus (QM J87189), B. C. mcdonaldi (QM J30062), C. C. hoskini (QM J86950), D. C. adorus (QM J86979), E. C. pronarus (QM J86900).

FIGURE 21. Distribution of Cyrtodactylus hoskini (diamonds), C. adorus (circles) and C. pronarus (squares). Open symbols indicate photographic record only.

FIGURE 26. Holotype of Cyrtodactylus pronarus (QM J86900).

FIGURE 27. Cyrtodactylus pronarus from Peach Creek in life (Photo: K. Aland).

FIGURE 28. Habitat of Cyrtodactylus pronarus at Peach Creek (Photo: A. Amey).