Research Article |
Corresponding author: Paul Oliver ( paul.oliver@unimelb.edu.au ) Academic editor: Aaron Bauer
© 2016 Paul Oliver, Stephen Richards, Mumpuni Mumpuni, Herbert Rösler.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Oliver PM, Richards SJ, Mumpuni, Rösler H (2016) The Knight and the King: two new species of giant bent-toed gecko (Cyrtodactylus, Gekkonidae, Squamata) from northern New Guinea, with comments on endemism in the North Papuan Mountains. ZooKeys 562: 105-130. https://doi.org/10.3897/zookeys.562.6052
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The diverse biota of New Guinea includes many nominally widespread species that actually comprise multiple deeply divergent lineages with more localised histories of evolution. Here we investigate the systematics of the very large geckos of the Cyrtodactylus novaeguineae complex using molecular and morphological data. These data reveal two widespread and divergent lineages that can be distinguished from each other, and from type material of Cyrtodactylus novaeguineae, by aspects of size, build, coloration and male scalation. On the basis of these differences we describe two new species. Both have wide distributions that overlap extensively in the foothill forests of the North Papuan Mountains, however one is seemingly restricted to hill and lower montane forests on the ranges themselves, while the other is more widespread throughout the surrounding lowlands. The taxon endemic to the North Papuan Mountains is related to an apparently lowland form currently known only from Waigeo and Batanta Island far to the west – hinting at a history on island arcs that accreted to form the North Papuan Mountains.
Arc accretion, Endemism, Indonesia, lizard, orogeny, Papua New Guinea, Papua Province, Sepik Basin
Integrated morphological and molecular investigations of the exceptionally diverse biota of New Guinea are confirming that many nominally widespread species comprise multiple deeply divergent lineages (
The Bent-toed geckos (Cyrtodactylus) are the most species-rich radiation of geckos in the world (
Cyrtodactylus novaeguineae
Here we present an analysis of genetic and morphological variation within geckos referred to Cyrtodactylus novaeguineae from across New Guinea (with a focus on the much better sampled eastern half of the island). These data reveal two genetically and morphologically distinct lineages in northern New Guinea that are not conspecific with this nominal taxon - and which we therefore describe as new taxa. We also review the biogeography of these geckos in the context of recent phylogenetic investigations into the role that orogeny and arc accretion has played in shaping the biota of northern New Guinea.
DNA sequence data was amplified from tissues subsampled from frozen or ethanol collections lodged at the Australian Biological Tissue Collection (
Sequence data from the NADH dehydrogenase subunit 2 (ND2) for 13 nominal C. novaeguineae were aligned with a subset of Papuan Cyrtodactylus sequence data published elsewhere, and chosen to include all potential close relatives (
Our final alignment included up to 987 bp of data and was aligned using the MUSCLE algorithm (
Measurements taken with digital calipers to the nearest 0.1 mm largely follow
We counted left and right enlarged supralabials to both the midpoint of the eye and to the rictus, left and right infralabials to rictus, dorsal tubercle rows between the lateral folds (not including the lateral fold) at the midpoint of body, ventrals at midpoint of the body in transverse series between ventral folds, the number of narrow lamallae distal to the inflection of the digit (not including the claw sheath), the number of wide subdigital lamellae proximal to the inflection of the joint under the first and fourth digits of the left manus and pes, precloacal and femoral pores where present, and postcloacal tubercles. Finally, we also recorded the extent of large tubercles on the lower jaw: absent, extending to the infra-angular region only, or extending across the throat.
We identify three major mitochondrial lineages of ‘C. novaeguineae’: ‘south’ – from three sites to the south of the Central Cordillera in Western and Gulf Provinces of Papua New Guinea; ‘north 1’ – North Papuan Mountains (Foja, Bewani and Torricelli Mountains); and ‘north 2’ –northern lowlands and foothills of Papua New Guinea from close to the Indonesian border in Sandaun Province east as far as Morobe Province. A clade comprising ‘north 1’, ‘south’, and Cyrtodactylus zugi from Batanta Island off the western coast of New Guinea is strongly supported. Within this clade there is strong support for the close relationship of C. zugi and ‘north 1’ (Figure
Maximum likelihood phylogeny for the Cyrtodactylus novaeguineae complex. The major lineages identified and the relationships between them estimated using RAxML and approximately 900bp of the mitochondrial ND2 gene are shown. Posterior probability support values shown at key nodes. Known altitudinal distribution of all recognised species in metres above sea level (a.s.l.) also indicated.
Each of the three genetic lineages shows consistent differences in colour pattern, body size and aspects of scalation (see further details in Table
Comparison of key morphological characters for members of the Cyrtodactylus novaeguineae complex. Key diagnostic traits for species are in bold.
Character | Cyrtodactylus equestris sp. n. | Cyrtodactylus ‘novaeguineae’ | Cyrtodactylus rex sp. n. | Cyrtodactylus zugi |
---|---|---|---|---|
SVL (max) | 139 mm | 129 mm | 172 mm | 159 mm |
HW/SVL | 0.19–0.23 | 0.17–0.19 | 0.20–0.24 | 0.21-0.22 |
HH/HW | 0.11–0.14 | 0.11–0.13 | 0.11–0.14 | 0.12-0.13 |
Dorsal tubercle rows | 19–25 | 21–22 | 21–27 | 21-24 |
Ventrals | 42–59 | 31–44 | 49–60 | 45-52 |
Supralabials | 11–15 | 11–15 | 10–15 | 10–12 |
Infralabials | 10–13 | 11–13 | 11–14 | 11–13 |
Extent of throat tubercles | usually across posterior throat | usually across posterior throat | usually across posterior throat | none |
Number of pores | up to 39 | up to 43 | up to 38 | unknown |
Pore arrangement | Tripartite | continuous | continuous | unknown |
Ventral pattern | sparse maculations | unpatterned | dark brown reticulations | very sparse maculations |
Darkest band colour | medium brown | dark brown | dark brown | dark brown |
Dark dorsal markings on body (including nuchal band) | 3 | 4–5 | 4 | 4 |
Dark markings > .5× width of body | Some | all | some | some |
Concordant patterns of genetic and morphological variation indicate that at least three evolutionarily distinct lineages (species) have been confounded within Cyrtodactylus novaeguineae. No genetic samples are available from the vicinity of the type locality so determining which, if any, of these populations represents true C. novaeguineae relies on comparisons of morphology. The two male syntypes of C. novaeguineae (RENA (formerly
A colour plate accompanying the description of C. novaeguineae (Schlegel, 1834) – presumably of one of the syntypes although this is not clear – shows three continuous and clearly defined brown dorsal bands (Figure
The populations from southern New Guinea that we here refer to C. novaeguineae can be distinguished from other Papuan Cyrtodactylus by the following unique combination of characters – moderately large size (SVL to 129 mm), narrow head (HW/SVL0.18–0.19), enlarged tubercles on the infra-angular region and often extending across the posterior region of the throat, mid dorsal tubercles in 21 to 22 rows at midpoint of body, subcaudal scales not transversely widened, moderate number of mid-body ventral scales (31–44) and a continuous or near-continuous, relatively straight, row of femoral and precloacal pores in adult males (up to at least 43 pores in total).
The two northern forms (‘north 1’ and ‘north 2’) differ from C. novaeguineae from southern New Guinea (including the types) in having broader heads and in being of slightly to much larger size (Figure
AMS R135520 adult male with everted left hemipenis and completely regrown tail, Papua New Guinea, Sandaun Province, Torricelli Mountains, Mt. Sumbau (3°23'S, 142°31'E, between 1000–1200 m a.s.l.), collected by P. German, 10 March 1990, with frozen tissue at the South Australian Museum (ABTC50282).
(n = 6). Papua New Guinea: AMS R119547 Sandaun Province, Torricelli Mtns, Wigote (3°25'S, 142°09'E), collected by T. Flannery, 20 July 1985;
(n = 5). Papua New Guinea:
A large Cyrtodactylus (SVL to 139 mm), with a moderately broad head (HW/SVL 0.19–0.22), enlarged tubercles on the infra-angular region and often extending across the posterior throat, mid-dorsal tubercles in 19 to 25 rows at midpoint of body, subcaudal scales not transversely widened, high number of mid-body ventral scale rows (42–59), femoral pores in two separated rows of 9–19, usually with a further medial precloacal row of 6–13 pores (up to 39 pores in total), venter relatively plain brown with at most scattered darker brown maculations, and dorsum with three distinct to indistinct medium-brown transverse bands on relatively plain light brownish-grey background.
A moderately large (113 mm SVL) and slender gecko. Head large (HL/SVL 0.28), moderately wide (HW/SVL 0.21) and clearly distinct from neck. Snout rounded in dorsal profile, broadly truncate in lateral profile, eye to naris distance longer than eye diameter (EN/EYE 1.4), loreal region slightly inflated, interorbital region and top of snout concave, canthus rostralis rounded, weakly defined. Eyes large (EYE/HL 0.26), pupil vertical, supraciliaries extending from anteroventral to posterodorsal edge of orbit, longest at the anterodorsal corner. Ear opening rounded, bordered by distinct dorsal skin fold.
Rostral rectangular, wider than high, with medial suture extending approximately halfway from dorsal edge towards ventral edge, bordered dorsally by two flattened nasals and single tiny internasal. Nares bordered by first supralabial (point contact), rostral, nasal, 2–3 enlarged postnasals and 2–3 tiny granular postnasals. Supralabials generally wider than high, 10 on right, 11 on left, 8 to midpoint of eye. Head, temporal and nuchal scales small and granular, interspersed with numerous enlarged weakly conical tubercles, approximately 3–4 times width of surrounding scales, on temporal and posterior nuchal regions. Enlarged infralabials slightly to much wider than high, 11 on right and 10 on left, bordered by rows of slightly enlarged scales that grade into small granular gular scales. Mental slightly wider than long, broadly triangular, but with distinctly concave edges at contact with postmentals, in contact with first infralabials. Scattered small conical tubercles (approximately twice size of surrounding scales) in the infra-angular regions of the lower jaw only.
Body moderately robust (TrK/SVL 0.44) with distinct ventrolateral folds. Moderately tuberculate, tubercles along lateral fold heterogeneous, up to 3 times larger than surrounding scales. Dorsum with approximately 23 rows (not including lateral fold) of often keeled tubercles up to 4 times width of surrounding granular scales. Ventral scales much larger than dorsal scales, increasing in size medially, arranged in approximately 39 rows at midpoint of body. Several continuous rows of enlarged femoral scales, posterior row extending almost to knee, distinctly larger and contrasting against granular posterior femorals. Precloacal pores in a series of 8, femoral pores in individual series of 15–16, respective series separated by 7 poreless scales.
Limbs moderately robust, forelimbs (FA/SVL 0.14) shorter and less robust than hindlimbs (CS/SVL 0.19). Lateral and dorsal surfaces of antebrachium and crus with numerous conical tubercles. Digits long and well developed, inflected at basal interphalangeal joints; subdigital lamellae smooth, rounded and expanded proximal to digital inflection (8-12-11-13-11 manus; 9-12-15-15-13 pes); narrow distal to digital inflection (9-10-11-11-11 manus; 7-12-12-14-13 pes) (counts not including ventral claw sheath); large recurved claws sheathed by a dorsal and ventral scale.
Tail almost completely regrown, scalation heterogeneous and irregular. Cloacal sacs swollen and prominent, each with 3 rounded cloacal spurs at anterior edge.
(in mm).SVL 113, TL 97, OT 13, TrK 49.5, HW 23.4, HH 13.1, HL 32.2, EN 11.6, IN 4.2, EYE 8.3, EAR 2.0, FA 15.3, CS 21.5.
Dorsal pattern consisting of alternating light brown and medium brown regions. Nuchal band medium brown, posterior edge triangular with thin continuous dark brown margin and extending along dorsum to level of forelimb insertion, anterior edge deeply notched and less clearly margined. Nuchal dark band bordered posteriorly by a deeply notched light brown band with distinct thin dark brown edging on medial anterior and posterior edges, and extending anteriorly onto lower jaw. Subsequent dark bands not deeply notched and less distinctly margined, but generally with at least some dark brown edging at their midpoint. Dorsal surface of head medium brown, darker anteriorly, without pattern, with the exception of a pair of small curved dark brown lines on the nape. Lower lateral region of head whitish brown, strongly demarcated against upper lateral and dorsal brown colouration. Ventral colouration dirty brown with scattered darker brown maculations on the throat and and across the venter. Limbs medium brown dorsally, slightly lighter ventrally, largely unpatterned except for scattered dark maculations and very small blotches on the hindlimbs. Stub of original tail medium brown dorsally with a pair of smeared very dark brown markings. Regrown tail plain light brown on all surfaces.
The type series includes 4 adult males (with fully expressed pore series) varying from 113–129 mm SVL, two adult females both of 139 mm, and one juvenile male of 104 mm. Mensural data for the type series are summarized in Table
AMS R135520 |
|
|
|
|
|
AMS R119547 | |
---|---|---|---|---|---|---|---|
Sex | m | m | M | m | f | f | juv |
SVL | 113 | 129 | 129 | 125 | 139 | 139 | 104 |
TL | 97 | 148 | 104 | 151 | 119 | 129 | 135 |
OT | 13 | 148 | 18 | 151 | 22 | 69 | 135 |
TrK | 49.5 | 57.7 | 57.1 | 56.7 | 60.8 | 61.0 | 51.3 |
HW | 23.4 | 26.5 | 26.8 | 24.4 | 26.8 | 29.7 | 20.6 |
HH | 13.1 | 14.2 | 15.0 | 13.9 | 16.1 | 17.1 | 13.1 |
HL | 32.2 | 34.1 | 35.3 | 32.7 | 34.8 | 39.1 | 27.6 |
EN | 11.6 | 12.4 | 13.1 | 11.6 | 11.4 | 4.5 | 10.4 |
IN | 4.2 | 5.2 | 5.1 | 4.7 | 4.8 | 5.1 | 3.7 |
EYE | 8.3 | 7.7 | 7.9 | 8.1 | 7.8 | 8.7 | 7.7 |
EAR | 2.0 | 1.8 | 1.1 | 1.7 | 2.1 | 1.7 | 1.7 |
FA | 15.3 | 19.5 | 19.7 | 19.1 | 20.0 | 19.9 | 14.9 |
CS | 21.5 | 22.1 | 23.1 | 22.2 | 23.0 | 25.5 | 18.7 |
Dorsum generally with alternating transverse regions of light and medium brown, however the width and distinctiveness of these region varies. Some variation in the intensity of colouration may be ontogenetic. On the largest specimens the medium brown regions are relatively narrow, and not or only weakly defined by dark brown edging, giving the overall impression of a somewhat faded pattern. On smaller specimens the transverse bands are more distinct and strongly defined. An indistinct trace of medium brown mottling or barring is also sometimes apparent on the dorsal and lateral surfaces of the hindlimbs. Venter medium to light brown, sometimes with very scattered darker brown maculations. Original tails with alternating medium-brown dorsal blotches and light-brown to creamish regions, border between colours often sharply defined by dark- brown edging. Regrown tails creamish or light brown with at most a few very indistinct light brownish streaks and patches. Iris in life deep chestnut brown with dark brown vermiculations (Figure
Cyrtodactylus equestris sp. n. can be distinguished from most other Cyrtodactylus by its large size (males to 129 mm, females to 139 mm), including all species from west of Lydekker’s Line (maximum size <130 mm). It can be differentiated from the other large Papuan taxa as follows. Cyrtodactylus equestris sp. n. differs from Cyrtodactylus loriae and Cyrtodactylus serratus in having enlarged tubercles on the infra-angular region and often extending across the throat (vs. absent), a lower number of pores (up to 39 vs. up to 81) in a discontinuous series (vs. continuous), and in lacking enlarged tubercles extending the length of the tail (vs. C. serratus only). Cyrtodactylus equestris sp. n. differs from members of the C. lousiadensis group (C. epiroticus, C. klugei, C. lousiadensis, C. murua, C. robustus, C. salomonensis and C. tripartitus) in its smaller subcaudal scales, in having tubercles on the infra-angular region and throat, and in its more poorly defined light-brown bands or blotches on the dorsum (vs. strongly defined and unbroken transverse brown banding). Cyrtodactylus equestris sp. n. differs from C. zugi in its smaller size (139 vs. 159 mm SVL), more extensive tuberculation that usually extends across the throat (vs. on infra-angular region only), and dorsal colour pattern on torso consisting of light-brown transverse bands on a plain greyish-brown background (vs. alternating dark brown blotches on a mottled dark-grey and off-white background). Cyrtodactylus equestris sp. n. differs from C. irianjayaensis by its smaller size (139 vs. 163 mm SVL), the presence of enlarged tubercules usually extending across the throat (vs. infra-angular region only) and its higher number of femoral and precloacal pores (24–39 vs. 7–16). Cyrtodactylus equestris sp. n. differs from other populations of Cyrtodactylus here referred to C. novaeguineae (both syntypes and genotyped material) in its wider head (HW/SVL 0.19–0.23 vs. 0.18–0.19), larger size (SVL 139.0 vs. 129.0) and tripartite femoral and precloacal pore arrangement (vs. continuous or at most one poreless intervening scales).
Known from scattered localities in the Foja, Torricelli and possibly the Adelbert Ranges (see below) of northern New Guinea (Figure
Equestris latin for knight, in reference to the relative size of this species – large for the genus, but still subordinate to some of its near relatives.
The referred material include two specimens in the American Museum of Natural History (
(n =19). Papua New Guinea:
(n = 7). Papua New Guinea.
A very large Cyrtodactylus (SVL to 172 mm), with a very broad head (HW/SVL 0.20–0.24), enlarged tubercles across the infra-angular region and often extending across the throat, mid-dorsal tubercles in 21 to 27 rows at midpoint of body, subcaudal scales not transversely widened, high number of mid-body ventral scales in transverse series (49–60), moderate number of femoral and precloacal pores (20–38) in a nearly continuous chevron, narrow dark brown barring on the throat, labials and often venter, and dorsal colour pattern on torso including indistinctly defined alternating dark-brown, medium-brown and whitish regions.
A very large (169 mm SVL) and robust gecko. Head very large (HL/SVL 0.27), very wide (HW/SVL 0.23) and clearly distinct from neck. Snout longer than eye diameter, eye to naris distance longer the eye (EN/EYE 1.4), curved in dorsal profile, broadly truncate in lateral profile, mid-loreal region slightly inflated, interorbital region and top of snout slightly concave, canthus rostralis weakly defined. Oval patch of skin missing from top of snout. Eyes large (EYE/HL 0.24), pupil vertical, supraciliaries extending from anteroventral to posterodorsal edge of orbit, longest at the anterodorsal edge. Ear opening roughly circular, bordered by distinct dorsal skin fold.
Rostral broadly rectangular, approximately 1.5 times wider than high with medial suture extending approximately 60% from dorsal edge towards ventral edge, bordered dorsally by two nasals and three smaller internasals. Nares bordered by first supralabial (point contact), rostral, nasal, and series of five to eight granular postnasals. Supralabials generally slightly wider than high, 13 right, 14 left, 10 to midpoint of eye. Head, temporal and nuchal scales small and granular with conical tubercles approximately 2–3 times width of surrounding scales densely distributed across the temporal and nuchal regions. Enlarged infralabials to rictus 14 right, 13 left, anterior infralabials higher than wide, posterior infralabials wider than high, infralabials bordered by rows of enlarged scales that grade into small granular gular scales. Mental triangular, approximately as wide as long, bordered by first infralabials and two pentagonal postmentals. Numerous wide flat tubercles present across posterior region of throat.
Body robust (TrK/SVL 0.43) with distinct ventrolateral folds. Skin heavily tuberculate dorsally and laterally, 33–34 prominent enlarged tubercles along lateral folds, dorsum with up to 23 rows (not including lateral fold) of enlarged conical tubercles up to four times width of surrounding small and granular scales. Ventral scales larger than dorsal scales, increasing in size medially, arranged in approximately 54 rows at midpoint of body, one or two poorly defined rows of enlarged ventral tubercles present just inferior to the lateral fold. Enlarged precloacal and femoral scales in three rows, posterior row longest (47 scales) and extending laterally approximately two thirds length of femur, medial scales distinctly larger.
Limbs robust, forelimbs shorter (FA/SVL 0.15) and less robust than hindlimbs (CS/SVL 0.17). Lateral and dorsal surfaces of hindlimbs with numerous enlarged conical tubercles. Digits long and well developed, inflected at basal interphalangeal joints; subdigital lamellae smooth, rounded and expanded proximal to joint inflection (11–12–13–15–11 manus; 10–14–14–15–9 pes); narrow distal to digital inflection (7–9–10–10–11 manus; 8–8–12–11–11 pes) (not including ventral claw sheath); large recurved claws sheathed by a dorsal and ventral scale.
Tail original, partially fractured approximately halfway from base, long and moderately robust, numerous low conical tubercles on dorsal and lateral surfaces close to base, but not extending beyond anterior third of tail, subcaudal scales enlarged, not wider than long, arranged in series 2–4 scales wide, 4 rounded cloacal spurs.
(in mm).SVL 169, TL 177, OT 177, TrK 72.7, HW 38.1, HD HH 24.3, HL 45.1, EN 14.7, IN 6.4, EYE 10.6, EAR 3.2, FA 26.1, CS 29.3.
Dorsum consists of alternating regions of dark greyish-brown, medium grey, and light-grey to dirty off-white. Four dark-brown regions most clearly defined, and consisting of three paired sets of oval, pentagonal and triangular blotches between fore- and hindlimbs, and an additional distinct dark-brown triangular nuchal patch anterior to insertion of forelimbs, and extending anterio-laterally as a stripe through eye and along dorsal edge of supralabials. Ventro-lateral regions of head with wide off-white stripe extending to lower edge of supralabials. Supraciliaries and dorsal tip of snout dark brown. Limbs and toes dirty grey with broad indistinct dark-brown bands on upper and lateral surfaces. Ventral ground colouration off-white with brownish tinge and extensive dark-brown flecks, often covering just a single scale, but also coalescing to form four distinct sets of jagged transverse bars on throat, and less prominent bars and ocelli on torso. Dorsal and lateral surfaces of tail dirty grey with four indistinctly edged dark-brown blotches or bands, and extensive smaller dark brown maculations, stripes or blotches. Subcaudal surfaces dark-brown with scattered lighter grey spots.
The type series of 20 specimens includes five adult males with expressed pores (SVL 152–165 mm), 10 females (128–172 mm), and five juveniles or subadults (72–127 mm). Mensural data for the type series are summarized in Table
Males (n = 5) | Females (n = 10) | Immatures (n = 5) | ||||
---|---|---|---|---|---|---|
Range | Mean | Range | Mean | Range | Mean | |
SVL | 127–165 | 153 | 128–172 | 154.3 | 73–111 | 89.3 |
TL | 16–162 | 118.0 | 23–177 | 122.9 | 74–112 | 94.0 |
OT | 11–137 | 40.6 | 11–142 | 37.2 | 74–112 | 94.0 |
TrK | 54.9–78.2 | 70.0 | 47.0-87.2 | 69.8 | 34.4–53.7 | 42.4 |
HW | 27.1–35.0 | 32.5 | 28.6–38.1 | 33.4 | 15.1–23.1 | 18.9 |
HH | 16.6–21.8 | 19.8 | 15.5–24.3 | 19.7 | 9.3–14.0 | 11.7 |
HL | 36.5–43.3 | 41.1 | 35.6–45.6 | 41.4 | 20.6–29.9 | 25.2 |
EN | 12.2–14.5 | 13.6 | 12.1–15.1 | 13.8 | 7.1–10.7 | 8.7 |
IN | 4.9–6.4 | 5.8 | 5.2–6.4 | 5.9 | 2.8–4.4 | 3.7 |
EYE | 8.7–10.4 | 9.5 | 8.1–10.9 | 9.9 | 4.8–7.4 | 6.4 |
EAR | 1.5–3.9 | 2.4 | 1.8–4.2 | 2.6 | 1.0–1.7 | 1.5 |
FA | 20.5–24.2 | 23.0 | 18.6–26.1 | 22.3 | 9.9–16.4 | 12.8 |
CS | 23.6–29.5 | 27.2 | 22.8–31.0 | 27.0 | 11.8–18.7 | 15.0 |
Dorsal pattern always consists of indistinctly defined alternating regions of dark grey brown, medium brown and dirty off-white. Dark grey-brown markings usually most clearly defined, but showing extensive variation in shape and size - usually less than half width of torso, but occasionally wider and varying in shape from small diamonds, transverse bands to paired blotches or triangles. Dark brown ventral barring always present, but on some specimens restricted to throat only, while in others forming a network across throat and venter. All specimens with at least some indistinct dark brown barring on toes and four or five dark brown longitudinal blotches or bands on original tails. Iris in life brick red with extensive fine brown vermiculations (Figure
All specimens heavily tuberculate with usually several indistinct rows of large tubercles extending as much as 10 mm inferior to lateral fold at midpoint of torso. Throat tuberculation varies in extent from a broad band spanning the posterior throat to concentrated in infra-angular regions and largely absent from the throat.
Cyrtodactylus rex sp. n. is readily distinguished from most other Cyrtodactylus by its very large size (SVL up to 172 mm vs generally < 130mm). It further differs from the relatively small number of other large Papuan species as follows. Cyrtodactylus rex sp. n. differs from C. loriae and C. serratus in having enlarged tubercles on the infra-angular region and often extending onto and across the throat (vs absent from both regions), a lower number of pores (up to 38 vs. up to 81), and in lacking enlarged tubercles extending the length of the tail (vs. C. serratus only). Cyrtodactylus rex sp. n. differs from members of the C. lousiadensis group (C. epiroticus (with which it is sympatric in Morobe Province), C. klugei, C. lousiadensis, C. murua, C. robustus, C. salomonensis and C. tripartitus) by its much smaller subcaudal scales, the presences of extensive tubercles on infra-angular region and often the throat, and in its much more poorly defined dark bands or paired blotches on the dorsum (vs. distinctly edged, unbroken transverse light and dark-brown bands). Cyrtodactylus rex sp. n. differs from C. zugi by the presence of dark-brown barring on the throat and venter, tuberculation often extending across the throat (vs. on infra-angular region only), and dorsal colour pattern on torso consisting of alternating indistinct dark-brown, medium brown and whitish regions (vs. alternating dark-brown and off-white). Cyrtodactylus rex sp. n. differs from C. irianjayaensis by the presence of dark-brown barring on the throat and venter (vs. plain and unpatterned), tubercles often extending across the throat (vs. infra-angular region only), dorsal colour pattern on torso consisting of alternating indistinct dark-brown, medium brown and whitish regions (vs. very wide brown transverse blotches on a lighter greyish brown ground colour), and higher number of femoral and precloacal pores (21–38 vs. 7–16). Cyrtodactylus rex sp. n. differs from all populations referred to C. novaeguineae in its wider head (HW/SVL 0.21–0.24 vs. 0.18–0.19) and larger size (SVL 172 vs. 129 mm), and differs from C. equestris sp. n. in its larger size (SVL 172 vs. 139 mm), in having a continuous (or nearly so) row of femoral and precloacal pores, presence of dark barring on the throat and ventral surfaces of body (vs. absent), and ‘messier’ dorsal colouration of alternating indistinct dark-brown, medium brown and whitish regions (vs. light-brown transverse bands or blotches on relatively plain light brownish-grey background).
Widespread in northern Papua New Guinea, extending from Sandaun Province in the west to Morobe Province in the east (Figure
The holotype was collected on a low ridge in Sago-dominated swamp forest. Other specimens were collected in lowland and foothill forest at altitudes ranging from near sea level up to 690 m a.s.l.
From the latin for king as it is the largest of the over 200 species of Cyrtodactylus, and amongst the largest of all known geckos (
The complex geological history of New Guinea has played a major role in shaping Papuan biodiversity (
The two new geckos described here have overlapping, yet somewhat complementary distributions: Cyrtodactylus equestris sp. n. is seemingly restricted to hill and lower montane forests on the North Papuan Mountains themselves, while C. rex sp. n. is more widespread throughout the surrounding lowlands (Figure
In contrast to their broadly overlapping intraspecific distribution, the distribution of sister lineages to these two North Papuan Mountain Cyrtodactylus differs. On the one hand C. boreoclivus is closely allied to C. medioclivus, an allopatric lower montane form currently known only from a small area of the Central Cordillera (
The contrasting distribution of sister lineages in the North Papuan Ranges suggests endemism is accumulating through multiple processes - colonisation by taxa already associated with hill and lower montane habitats from the older Central Cordillera (eccentric endemism), accretion of pre-existing island arc biotas, and potentially even de novo shifts up elevational gradients within otherwise lowland lineages (centric endemism) (
Cyrtodactylus is also an exceptionally species rich genus of lizards with over 200 recognised species (
Specimens examined included material collected over the course of numerous independent field trips in Papua New Guinea and Papua Province, Indonesia, but we particularly thank the numerous staff and major donors to Conservation International for work in Indonesia and Papua New Guinea, and to
Registration numbers, GenBank numbers and localities for material included in genetic analyses.
Ingroup. Cyrtodactylus equestris:
Outgroups. Cyrtodactylus adorus: QM J86979, HQ401166, Australia, Queensland, Pascoe River; Cyrtodactylus arcanus: AMS R124559, JQ820314, Papua New Guinea, Madang Province, Bundi; Cyrtodactylus arcanus: (paratype) AMS R124560, JQ820319, Papua New Guinea, Madang Province, Bundi; Cyrtodactylus epiroticus:
Material examined for morphological comparisons.
Institutional abbreviations are as follows: Australian Museum (AMS), American Museum of Natural History (
Cyrtodactylus aaroni: