Research Article |
Corresponding author: Kin Onn Chan ( chankinonn@gmail.com ) Academic editor: Thomas Ziegler
© 2023 Kin Onn Chan, L. Lee Grismer, Fernando Santana, Pedro Pinto, Frances W. Loke, Nathan Conaboy.
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:
Chan KO, Grismer LL, Santana F, Pinto P, Loke FW, Conaboy N (2023) Scratching the surface: a new species of Bent-toed gecko (Squamata, Gekkonidae, Cyrtodactylus) from Timor-Leste of the darmandvillei group marks the potential for future discoveries. ZooKeys 1139: 107-126. https://doi.org/10.3897/zookeys.1139.96508
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A new species of limestone-dwelling Bent-toed gecko (genus Cyrtodactylus) is described from Nino Konis Santana National Park in the far-east region of Timor-Leste. Both genetic and morphological data strongly support the evolutionary distinctness of the new species, which we describe herein as Cyrtodactylus santana sp. nov. Phylogenetic analysis based on the ND2 mitochondrial gene inferred the new species as part of the C. darmandvillei group with close genetic affinities to C. batucolus, C. seribuatensis, C. petani, C. sadleiri, and two undescribed lineages from the Moluccas in Indonesia. The new species represents the first species of Cyrtodactylus identified at the species level from Timor-Leste and fills an important gap in our understanding of the biogeography and evolutionary history of Cyrtodactylus especially in the Wallacean region. Our results strongly suggest that the diversity of Cyrtodactylus in Wallacea is still underestimated and many more unnamed species remain to be described.
Biogeography, Gekkota, lizards, phylogenetics, systematics, taxonomy, Wallacea
The Southeast Asian island of Timor is the largest of the Lesser Sunda Islands and is located within the biogeographical region of Wallacea, bounded by Wallace’s Line in the west and Lydekker’s Line in the east. The Democratic Republic of Timor-Leste (hereafter referred to as Timor-Leste) is a sovereign country occupying the eastern half of the island of Timor and includes the islands of Ataúro, Jaco, and the semi-enclave of Oecusse, a Special Administrative Region located in the western part of Timor. The western half of Timor is part of the Indonesian province of East Nusa Tenggara (Fig.
Upper left inset: Map of Sundaland (blue), Wallacea (green), and the Australo-Papuan region (orange) including Wallace’s and Lydekker’s lines that demarcates the boundaries of the three biogeographic regions. The red box denotes Timor and the surrounding islands. Right: An expanded map of Timor-Leste and the surrounding islands. Territories belonging to Timor-Leste are shaded in red. The red star indicates the location of the field site in the northeastern sector of the Nino Konis Santana National Park.
The herpetofaunal diversity of Timor-Leste is relatively poorly known, largely due to centuries of conflict and political instability that have hampered biological research. The first comprehensive report on the herpetofauna of Timor-Leste was published by
Fieldwork was conducted at the adjacent caves of Lene Hara and Napana Wei (8.411758°S, 127.293321°E; 152 m a.s.l.) in the northeastern sector of Nino Konis Santana National Park (NKS) on 30 August 2022. Specimens were euthanised using MS-222, fixed in 10% formalin, and transferred to 70% ethanol for long-term preservation. Liver samples were dissected and stored in 95% ethanol before fixation. All specimens are deposited at the Zoological Reference Collection (ZRC) of the Lee Kong Chian Natural History Museum, Singapore (LKCNHM).
We selected three (of the ten collected) specimens for DNA sequencing. The NADH dehydrogenase subunit 2 (ND2) mitochondrial gene was sequenced using the primers L4437 (AAGCTTTCGGGCCCATACC) and H5934 (AGRGTGCCAATGTCTTTGTGRTT) (
The following morphological data were collected following
To eliminate bias stemming from ontogenetic variation (
All supplementary material associated with this study can be obtained from the online version of this manuscript and the Figshare repository (https://doi.org/10.6084/m9.figshare.21359970.v1).
The final sequence alignment comprised 1566 base pairs, 1297 variable sites, 1141 parsimony informative sites, and 23.2% missing data. The best substitution model scheme for the IQ-TREE analysis was TVM + F + I + G4 for the 1st codon position of ND4 and tRNAs, TIM + F + I + G4 for the 2nd codon position, and GTR + F + I + G4 for the 3rd codon position. The phylogenetic analysis recovered the new population within the darmandvillei group (sensu
Lower: Genus-wide phylogeny based on all published sequences of described and undescribed lineages of Cyrtodactylus (see Suppl. material
A Maximum-likelihood phylogeny of the Cyrtodactylus darmandvillei group with boxplots showing the distribution of pairwise uncorrected p-distances (ND2 gene) between each corresponding taxon and all other taxa within the C. darmandvillei group B plot of PCA scores based on a subset of ten continuous characters.
For the PCA analysis, only PC1 had eigenvalues above 1.0 indicating that most variation (80%) is captured along the first axis (Table
Summary statistics and loadings for the PCA analysis. Character abbreviations are defined in Materials and methods.
PC1 | PC2 | PC3 | PC4 | PC5 | PC6 | PC7 | PC8 | PC9 | PC10 | |
---|---|---|---|---|---|---|---|---|---|---|
Standard deviation | 2.84 | 0.89 | 0.57 | 0.49 | 0.44 | 0.41 | 0.28 | 0.26 | 0.22 | 0.18 |
Proportion of Variance | 0.80 | 0.08 | 0.03 | 0.02 | 0.02 | 0.02 | 0.01 | 0.01 | 0.01 | 0.00 |
Cumulative Proportion | 0.80 | 0.88 | 0.92 | 0.94 | 0.96 | 0.98 | 0.99 | 0.99 | 1.00 | 1.00 |
Eigenvalue | 8.05 | 0.79 | 0.33 | 0.24 | 0.20 | 0.17 | 0.08 | 0.07 | 0.05 | 0.03 |
SVL | 0.31 | 0.23 | 0.55 | 0.28 | -0.65 | 0.11 | -0.12 | -0.02 | 0.06 | 0.09 |
ForL | 0.34 | 0.13 | 0.04 | -0.23 | 0.23 | -0.37 | -0.51 | 0.04 | -0.21 | 0.57 |
TibL | 0.34 | -0.18 | -0.14 | -0.02 | -0.07 | -0.11 | -0.20 | 0.78 | 0.20 | -0.36 |
AG | 0.32 | 0.20 | 0.45 | 0.03 | 0.56 | 0.03 | -0.08 | -0.21 | -0.07 | -0.54 |
HL | 0.34 | 0.08 | -0.05 | -0.33 | -0.10 | 0.30 | 0.44 | 0.19 | -0.66 | 0.03 |
HD | 0.30 | 0.33 | -0.61 | 0.43 | -0.16 | -0.27 | -0.02 | -0.27 | -0.18 | -0.22 |
ED | 0.29 | -0.51 | 0.08 | 0.62 | 0.29 | 0.03 | 0.27 | 0.05 | -0.04 | 0.33 |
EE | 0.33 | -0.02 | -0.31 | -0.10 | 0.07 | 0.74 | -0.28 | -0.20 | 0.33 | 0.12 |
EN | 0.33 | 0.26 | -0.01 | -0.26 | 0.06 | -0.26 | 0.57 | -0.04 | 0.57 | 0.18 |
IOD | 0.27 | -0.64 | 0.01 | -0.34 | -0.29 | -0.25 | -0.05 | -0.45 | -0.01 | -0.21 |
The ANOVA and TukeyHSD posthoc test showed that the new population is significantly different from C petani in all assessed characters; from C. batucolus for the characters TibL and IOD; and from C. seribuatensis for the characters ForL and EN (Table
Results of the Tukey posthoc test showing the p-values for all pairwise comparisons. Values highlighted in green represent p < 0.05, whereas those in red represent p > 0.05.
SVL | ForL | TibL | AG | HL | HD | ED | EE | EN | IOD | |
---|---|---|---|---|---|---|---|---|---|---|
petani-batucolus | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.06 | 0.00 | 0.00 | 0.53 |
santana-batucolus | 0.32 | 0.92 | 0.04 | 0.15 | 0.81 | 0.78 | 0.11 | 0.26 | 0.69 | 0.00 |
seribuatensis-batucolus | 0.46 | 0.03 | 0.94 | 0.02 | 0.97 | 0.02 | 0.40 | 0.95 | 0.00 | 0.00 |
santana-petani | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
seribuatensis-petani | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.02 | 0.00 | 0.00 | 0.00 | 0.00 |
seribuatensis-santana | 1.00 | 0.00 | 0.09 | 0.58 | 0.50 | 0.08 | 0.86 | 0.07 | 0.00 | 0.48 |
Comparisons of discrete and meristic characters among species of the Cyrtodactylus darmandvillei group. NA = not applicable; ? = unknown or not assessable.
Cyrtodactylus santana sp. nov. | C. batucolus | C. darmandvillei | C. jellesmae | C. kimberleyensis | C. petani | C. sadleiri | C. seribuatensis | |
---|---|---|---|---|---|---|---|---|
Max SVL | 74 | 75.2 | 75 | 63 | 45 | 57.2 | 88 | 75 |
Tuberculation moderate to strong | yes | yes | yes | yes | no | yes | yes | yes |
Tubercules on forelimbs | yes | yes | yes | yes | no | yes | yes | yes |
Tubercules on hindlimbs | yes | yes | yes | yes | no | yes | yes | yes |
Tubercules on head and/or occiput | yes | yes | yes | yes | no | yes | yes | yes |
Paravertebral tubercles | 23–27 | 30–35 | 17–20 | ? | 16–18 | 20–25 | 22–25 | 27–35 |
Proximal subdigital lamellae broad | yes | yes | yes | yes | yes | yes | yes | yes |
Subdigital lamellae on 4th toe | 15–19 | 17–19 | ? | ? | 16 | 17–18 | 19–24 | 19–22 |
Ventral scales | 42–48 | 38–42 | 36–40 | 40–45 | 36 | 30–35 | 34–42 | 32–39 |
Deep precloacal groove | no | no | no | no | no | no | yes | no |
Enlarged precloacal scales | yes | yes | ? | no | no | yes | yes | yes |
Enlarged femoral scales | yes | yes | ? | no | no | yes | yes | yes |
Precloacal and femoral pores continuous | yes | yes | ? | NA | NA | yes | NA | yes |
Precloaco-femoral pores | 43–45 | 43–46 | ? | NA | NA | 31–35 | NA | 42–45 |
Enlarged median subcaudals | no | no | yes | no | no | no | no | no |
Taken together, the results from our analyses demonstrate that the new population from Timor-Leste is a strongly supported, distinct evolutionary lineage (Fig.
Holotype. ZRC 2.7672 (Fig.
The new species is a distinct evolutionary lineage that is closely related to C. batucolus, C. seribuatensis, C. petani, and C. sadleiri. It can be differentiated from other congeners by the following combination of characters: strong dorsal tuberculation present, 23–27 paravertebral tubercles, 15–19 subdigital lamellae on 4th toe, 42–48 ventral scales across midbody, deep precloacal groove absent, enlarged femoral and precloacal scales present, distinct blotches on top of the head absent, dorsal bands faint, whitish, lightly counter-shaded with dark brown.
Adult male SVL 68.6 mm; head moderate in length (HL/SVL 0.30), wide (HW/HL 0.65), somewhat flattened (HD/HL 0.40), distinct from neck, triangular in dorsal profile; lores weakly inflated, prefrontal region concave, canthus rostralis smoothly rounded; snout elongate (ES/HL 0.43) rounded in dorsal profile; eye large (ED/HL 0.23); ear opening elliptical, moderate in size (EL/HL 0.11), obliquely oriented; eye to ear distance greater than diameter of eye; rostral wider than high, concave, partially divided dorsally, bordered posteriorly by left and right supranasals and smaller medial postrostral (= internasal), bordered laterally by first supralabials; external nares bordered anteriorly by rostral, dorsally by a large, anterior supranasal and small, posterior supranasal, posteriorly by two postnasals, ventrally by first supralabial; 10 (R) 10 (L) squarish supralabials extending to just beyond dorsal inflection of labial margins tapering in size abruptly below midpoint of eye, first supralabial largest; nine (R) and eight (L) infralabials tapering smoothly posteriorly slightly beyond last supralabial posteriorly; scales of rostrum and lores raised, larger than granular scales on top of head and occiput; scales of occiput intermixed with slightly enlarged tubercles; dorsal superciliaries elongate, keeled; mental triangular, bordered laterally by first infralabials and posteriorly by left and right rectangular postmentals which contact medially; one row of slightly enlarged, elongate sublabials extending posteriorly to 6th infralabial; gular scales small, granular, grading posteriorly into slightly larger, flatter, throat scales which grade into larger, flat, smooth, imbricate, pectoral and ventral scales.
Body relatively short (AG/SVL 0.43) with well-defined ventrolateral folds; dorsal scales small, granular, interspersed with moderately sized, conical, semi-regularly arranged, keeled tubercles; tubercles extend from occiput to anterior one-third of tail; tubercles on occiput and nape relatively small, increases in size and density posteriorly; tubercles on pelvic region and hindlimbs largest and densest; approximately 15 longitudinal rows of tubercles at midbody; 27 paravertebral tubercles on body; 44 flat, imbricate, ventral scales between ventrolateral body folds, ventral scales much larger than dorsal scales; precloacal scales large, seven scales across base of precloacal region; precloacal depression weak (Fig.
Forelimbs moderate in stature, relatively short (ForL/SVL 0.17); granular scales of forearm slightly larger than those of body, interspersed with large, keeled tubercles; palmar scales slightly raised; digits well-developed, inflected at basal, interphalangeal joints; subdigital lamellae transversely expanded throughout its length; digits slightly more narrow distal to inflection; claws well-developed, sheathed by a dorsal and ventral scale; hind limbs more robust than forelimbs, moderate in length (TibL/SVL 0.18), covered dorsally by granular scales interspersed with larger, keeled tubercles and covered anteriorly by flat, slightly larger scales; ventral scales of thigh flat, imbricate, larger than dorsals; ventral tibial scales flat, imbricate; two rows of enlarged, flat, imbricate, femoral scales extend from knee to knee through the precloacal region where they are continuous with enlarged, precloacal scales; posterior row of enlarged femoral scales contains 41 contiguous pore-bearing scales extending from knee to knee forming a V-shape bordering the precloacal depression; postfemoral scales immediately posterior to the row of pore-bearing scales nearly one-half their size, forming an abrupt union on posteroventral margin of thigh; plantar scales low, slightly rounded; digits well-developed, inflected at basal, interphalangeal joints; subdigital lamellae transversely expanded throughout length of digit; digits more narrow distal to joints; 17 subdigital lamellae on right 4th toe, 16 on left; claws well-developed, sheathed by a dorsal and ventral scale.
Tail robust, original, tip broken; dorsal scales at base of tail granular becoming flatter posteriorly; no median row of transversely enlarged, subcaudal scales; subcaudal scales much larger than dorsal caudal scales; one pair of paravertebral and dorsolateral tubercle rows on either side of midline; distance between paravertebral tubercle rows much greater than distance between paravertebral and adjacent dorsolateral rows; caudal tubercles decrease in size posteriorly, extending approximately 40% length of tail; four enlarged, postcloacal tubercles at base of tail on hemipenial swelling; all postcloacal scales flat, imbricate.
Dorsal ground colour of head yellowish; neck, trunk, limbs, and tail brown; no distinct markings on top of head; pale loreal stripe extend from nostril to eye and continuing as a postorbital stripe that forms a faint forked pattern on occiput; area dorsal and ventral to the loreal and postorbital stripe counter-shaded with dark brown; six pale, faint, thin, irregular bands from nape to base of tail faintly counter-shaded anteriorly and posteriorly with dark brown; dark speckling and faint, cream-coloured blotches on limbs; pale body banding extend onto tail but not encircling tail (Fig.
ZRC 2.7674–76, ZRC 2.7678, and ZRC 2.7680–81 have broken tails. Some specimens have more distinct dorsal markings than others (Fig.
Raw morphological data for the type series. Character abbreviations are defined in Materials and methods.
ZRC 2.7672 | ZRC 2.7673 | ZRC 2.7674 | ZRC 2.7675 | ZRC 2.7676 | ZRC 2.7677 | ZRC 2.7678 | ZRC 2.7679 | ZRC 2.7680 | ZRC 2.7681 | |
---|---|---|---|---|---|---|---|---|---|---|
Type | Holotype | Paratype | Paratype | Paratype | Paratype | Paratype | Paratype | Paratype | Paratype | Paratype |
Sex | male | male | male | male | male | male | female | female | female | female |
SVL | 68.6 | 70 | 64.6 | 74 | 70.6 | 59.1 | 62.2 | 70 | 64.2 | 60.6 |
AG | 29.6 | 28.7 | 25.8 | 32.3 | 28 | 24.3 | 27.5 | 31.6 | 27.5 | 27.2 |
HumL | 7.7 | 8.3 | 7.8 | 8.8 | 9 | 6.9 | 7.6 | 8.6 | 7.9 | 6.7 |
ForL | 11.5 | 11.2 | 10 | 12 | 11.8 | 10 | 9.8 | 10.8 | 10 | 9.5 |
FemL | 17.6 | 17 | 14.8 | 17.1 | 16.3 | 14.4 | 15 | 17.2 | 16.6 | 14 |
TibL | 12.1 | 12 | 11.8 | 13.7 | 13.5 | 11 | 11.8 | 12.9 | 12 | 11.6 |
HL | 20.5 | 20.7 | 19.2 | 22.7 | 21.5 | 17.1 | 18.4 | 20.7 | 19.2 | 17.9 |
HW | 13.5 | 14 | 12.4 | 14.7 | 14.9 | 11.9 | 11.6 | 13.6 | 13.3 | 12 |
HD | 8.2 | 9.3 | 8 | 9.1 | 9.8 | 7.3 | 7.4 | 8.6 | 8.5 | 7.4 |
ED | 4.8 | 5.2 | 4.2 | 4.8 | 5.1 | 4.2 | 4.3 | 5.2 | 5.2 | 4 |
EE | 5.8 | 5.7 | 5.9 | 6.4 | 6.3 | 5 | 5.4 | 5.7 | 5.3 | 4.7 |
ES | 8.9 | 8.7 | 8 | 9.8 | 8.8 | 7.8 | 7.5 | 9.2 | 8.2 | 7.7 |
EN | 6.4 | 6.7 | 6.5 | 7.1 | 6.8 | 5.7 | 6 | 6.7 | 6.2 | 5.7 |
IO | 6.2 | 6.1 | 5.7 | 6.8 | 6.3 | 5.2 | 5.4 | 6 | 6 | 5.6 |
EL | 2.3 | 2.2 | 1.5 | 2.3 | 1.7 | 1.4 | 1.9 | 1.8 | 2 | 1.2 |
IN | 2.4 | 2.8 | 2.2 | 2.3 | 2.3 | 2 | 2 | 2.4 | 1.9 | 1.8 |
SL (R/L) | 10/10 | 10/11 | 11/11 | 11/12 | 12/11 | 10/10 | 11/11 | 11/11 | 10/11 | 12/11 |
IL (R/L) | 9/8 | 8/8 | 9/9 | 9/9 | 10/9 | 9/9 | 10/9 | 9/9 | 9/9 | 9/9 |
PVT | 27 | 25 | 27 | 27 | 25 | 23 | 26 | 27 | 24 | 24 |
TL4T | 17 | 15 | 16 | 18 | 19 | 15 | 15 | 15 | 15 | 16 |
TL4F | 17 | 17 | 17 | 17 | 18 | 15 | 18 | 18 | 18 | 18 |
VS | 44 | 45 | 48 | 42 | 48 | 45 | 47 | 47 | 42 | 42 |
FS | 28 | 28 | 28 | 26 | 27 | 25 | 27 | 27 | 26 | 26 |
PFP | 44 | 45 | 43 | 45 | 45 | ? | NA | NA | NA | NA |
Due to the large number of Cyrtodactylus species, we restrict our comparison to species within the darmandvillei group. The new species differs from C. batucolus by having fewer paravertebral tubercles (23–27 vs. 30–35), more ventral scales (42–48 vs. 38–42), lacking distinct blotches on top of a yellowish head, lacking dark paravertebral dorsal blotches on the body and tail, and having less distinct but well-defined pale-coloured dorsal bands (Fig.
Cyrtodactylus santana sp. nov. occurs in Lene Hara and Napana Wei caves within NKS. The nearest village is Tutuala in the municipality of Lautém. The larger distribution of this species is not yet known but it likely occurs in other limestone caves within NKS. There is a report of a similar-looking and unidentified Cyrtodactylus on Ataúro island (
Lizards were considerably more abundant in Napana Wei cave compared to Lene Hara cave (Fig.
Nino Konis Santana was a freedom fighter who led the Falintil militia against the Indonesian occupation of Timor-Leste. He was not only a fearless leader of the armed wing of the Resistance but also played a key role in peace initiatives, earning him a reputation as a peacemaker, diplomat, and statesman. The Nino Konis Santana National Park was named in honor of this national hero who was born in the suco (village in Tetum) of Tutuala, located within the boundaries of the park. The specific epithet santana is used as a noun in apposition referring to Nino Konis Santana National Park, which is the type locality of the new species.
Members of the darmandvillei group comprise lineages from Wallacea (Cyrtodactylus santana sp. nov., C. jellesmae, C. darmandvillei, C. sp. 1, C. sp. 2, C. sp. 3, and C. sp. 4), Sundaland (C. batucolus, C. petani, C. seribuatensis, C. sadleiri, C. cf. jatnai), and an island off the northern tip of Western Australia (C. kimberleyensis; Fig.
Our phylogenetic analysis also included several lineages of uncertain identities.
Based on currently available data, Cyrtodactylus santana sp. nov. is a nocturnal species occurring in limestone caves in the lowland tropical forest of NKS. We did not observe any lizards on the vegetation surrounding the caves. However, our observations are based on one night’s sampling effort and our supposition that this species occurs exclusively on limestone could be overturned with more extensive and intensive surveys. There is also a report of a similar-looking and unidentified Cyrtodactylus on Ataúro Island that is referred to as C. sp. ‘Ataúro coast’ in
We thank the following people and institutions who made this research possible:
Raimundo Mau (Director-General for Forests, Coffee, and Industrial Plant) for permits and logistical support; Manuel Mendes, Natalino Martins (Conservation International), Tan Heok Hui, Iffah Binte Iesa (LKCNHM), and Daniel Thomas (Singapore Botanic Gardens) for planning, logistical support, and field assistance.
Supplementary information
Data type: zip file
Explanation note: Maximum Clade Credibility Bayesian tree inferred using BEAST. Maximum Likelihood consensus tree inferred using IQ-TREE. Raw (not size corrected) measurements in mm used in the morphological analyses. Information on all sequences used in this study and their associated GenBank accession numbers (Suppl. material