Research Article |
Corresponding author: Anchalee Aowphol ( fsciacl@ku.ac.th ) Academic editor: Thomas Ziegler
© 2022 Natee Ampai, Attapol Rujirawan, Siriporn Yodthong, Korkhwan Termprayoon, Bryan L. Stuart, Perry L. Wood Jr, Anchalee Aowphol.
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:
Ampai N, Rujirawan A, Yodthong S, Termprayoon K, Stuart BL, Wood Jr PL, Aowphol A (2022) Hidden diversity of rock geckos within the Cnemaspis siamensis species group (Gekkonidae, Squamata): genetic and morphological data from southern Thailand reveal two new insular species and verify the phylogenetic affinities of C. chanardi and C. kamolnorranathi. ZooKeys 1125: 115-158. https://doi.org/10.3897/zookeys.1125.94060
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Two new insular rock geckos in the genus Cnemaspis are described from Ko Samui in Surat Thani Province and Ko Similan in Phang-nga Province, southern Thailand, based on a combination of morphological and mitochondrial NADH dehydrogenase subunit 2 (ND2) data. Both new species represent divergent lineages within the Cnemaspis siamensis species group. Cnemaspis samui sp. nov. is distinguished from other species in the group by having eight or nine supralabial and infralabial scales; 5–8 pore-bearing precloacal scales in males, pores rounded; 25–27 paravertebral tubercles, arranged randomly; 22–25 subdigital lamellae under 4th toe; enlarged median subcaudal scale row present; gular region, abdomen, limbs and subcaudal region yellowish only in males, and uncorrected pairwise divergences of 8.86–26.83% from all other species in the C. siamensis species group. Cnemaspis similan sp. nov. is distinguished from other species in the group by having eight or nine supralabial and seven or eight infralabial scales; one pore-bearing precloacal scale in males, pore rounded; 24 or 25 paravertebral tubercles, arranged randomly; 23 or 24 subdigital lamellae under 4th toe; no enlarged median subcaudal scale row; pale yellow reticulum on head, neck, flanks, belly and limbs in male only, and uncorrected pairwise divergences of 9.34–27.11% from all other species in the C. siamensis species group. Cnemaspis samui sp. nov. is found along granitic rocky stream outcrops of Hin Lad Waterfall, Ko Samui, Gulf of Thailand, while Cnemaspis similan sp. nov. occurs in granitic rocky outcrops near Ao Nguang Chang Bay, Ko Similan, Andaman Sea. The phylogenetic analyses confirmed that C. chanardi and C. kamolnorranathi are also nested within the C. siamensis species group, as previously hypothesized from morphology and color pattern characters.
Cnemaspis, integrative taxonomy, Island, phylogeny, Thailand
The rock gecko genus Cnemaspis Strauch, 1887 is one of the most diverse reptile genera, with 192 recognized species known to date (
Historically, the taxonomy and systematics of Thai Cnemaspis depended solely on data from morphology and color pattern characteristics (e.g.,
We conducted field surveys for Cnemaspis during 2015–2020 at five localities in southern Thailand. Morphological and mitochondrial DNA data analyses revealed that the Cnemaspis samples from Ko (= island) Samui in the Gulf of Thailand and Ko Similan in the Andaman Sea differed from all known congeners of Thai Cnemaspis. In addition, we obtained samples from the type localities of C. chanardi and C. kamolnorranathi. Herein, the two distinct insular populations of Cnemaspis are described as new species and genetic data are used to verify the phylogenetic placements of C. chanardi and C. kamolnorranathi within the C. siamensis group.
Fieldwork was conducted at five different localities in southern Thailand including (1) Pathio District, Chumphon Province in June 2017, (2) Kanchanadit District, Surat Thani Province in January 2019, (3) Nayong District, Trang Province in May 2016, December 2017, and July 2019, (4) Ko Samui, Surat Thani Province in September 2015, July 2018, and August 2020, and (5) Ko Similan, Mu Ko Similan National Park, Phang-nga Province in March 2018. Sampling was conducted by using visual encounter surveys both during the day (1000–1800 h) and at night (1900–2200 h). Ecological data (air temperature and relative humidity) were collected using a Kestrel 4000 Weather Meter. Habitat preferences (e.g., microhabitat, substrate type and habitat use) were also recorded. Geographical coordinates and elevation were taken using a Garmin GPSMAP 64s. At each locality, specimens were photographed and euthanized by cardiac injection of tricaine methane sulfonate (MS-222) solution (
Genomic DNA from 21 individuals of Cnemaspis (C. adangrawi, N = 2; C. chanardi, N = 4; C. kamolnorranathi, N = 5; C. siamensis, N = 2; Ko Samui samples, N = 4; and Ko Similan samples, N = 4) was extracted from liver tissue (Table
Voucher information, including locality, collection numbers, GenBank accession numbers and reference for the specimens used in the phylogenetic analyses. Voucher abbreviations are as follows:
Monte L. Bean Life Science Museum at Brigham Young University (
Species | Locality | Collection number | GenBank accession number | Reference |
---|---|---|---|---|
Outgroup | ||||
Cyrtodactylus bokorensis | Cambodia, Kampot |
|
KT013107 |
|
Dixonius melanostictus | Thailand (captive) | No number | HM997153 |
|
Dixonius siamensis | Cambodia, Pursat Province, Phnom Aural |
|
EU054299 |
|
Gekko gecko | Myanmar, Ayeyarwady Division, Myaungmya District |
|
JN019052 |
|
Gehyra mutilata | Cambodia, Pursat Province, Phnom Aural |
|
JN393914 |
|
Hemidactylus frenatus | Myanmar, Tanintharyi Division, Kaw Thaung District |
|
HM559629 |
|
Hemidactylus garnotii | Myanmar, Mon State, Kyait Hti Yo Wildlife Sanctuary |
|
EU268364 |
|
Ca Mau Clade | ||||
Cnemaspis boulengerii | Vietnam, Ca Mau Province, Con Dao Archipelago |
|
KM024710 |
|
|
KM024711 | |||
Cnemaspis psychedelica | Vietnam, Ca Mau Province, Hon Khoai Island |
|
KM024827 |
|
|
KM024828 | |||
chanthaburiensis group | ||||
Cnemaspis aurantiacopes | Vietnam, Kien Giang Province, Hon Dat Hill |
|
KM024692 |
|
|
KM024693 | |||
Cnemaspis caudanivea | Vietnam, Kien Giang Province, Hon Tre Island |
|
KM024714 |
|
Cnemaspis chanthaburiensis | Cambodia, Pursat Province, Phnom Dalai |
|
KM024716 |
|
Cnemaspis lineogularis | Thailand, Prachuap Khiri Khan Province, Kui Buri District, Wat Khao Daeng |
|
KY091231 |
|
ZMKU R 00728 | KY091233 | |||
Cnemaspis neangthyi | Cambodia, Pursat Province, O’Lakmeas |
|
KM024767 |
|
|
KM024768 | |||
Cnemaspis nuicamensis | Vietnam, An Giang Province, Nui Cam Hill |
|
KM024775 |
|
|
KM024776 | |||
|
KM024777 | |||
kumpoli group | ||||
Cnemaspis biocellata | Malaysia, Perlis, Kuala Perlis |
|
KM024707 |
|
|
KM024708 | |||
Malaysia, Perlis, Gua Kelam |
|
KM024709 | ||
Cnemaspis kumpoli | Malaysia, Perlis, Perlis State Park |
|
KM024745 |
|
|
KM024746 | |||
Cnemaspis monachorum | Malaysia, Kedah, Langkawi Archipelago, Pulau Langkawi |
|
KM024754 |
|
|
KM024755 | |||
Cnemaspis niyomwanae | Thailand, Trang Province, Thum Khao Ting |
|
KM024773 |
|
|
KM024774 | |||
Cnemaspis tarutaoensis | Thailand, Satun Province, Mueang Satun District, Ko Tarutao | ZMKU R 00761 | MK862117 |
|
ZMKU R 00763 | MK862118 | |||
ZMKU R 00764 | MK862119 | |||
argus group | ||||
Cnemaspis argus | Malaysia, Terengganu, Gunung Lawit |
|
KM024687 |
|
|
KM024688 | |||
Cnemaspis karsticola | Malaysia, Kelantan, Gunung Reng |
|
KM024736 |
|
|
KM024737 | |||
affinis group | ||||
Cnemaspis affinis | Malaysia, Penang, Pulau Pinang |
|
KM024682 |
|
Cnemaspis grismeri | Malaysia, Perak, Lenggong |
|
KM024722 |
|
Cnemaspis hangus | Malaysia, Pahang, Bukit Hangus |
|
KM024728 |
|
Cnemaspis harimau | Malaysia, Kedah, Gunung Jeri |
|
KM024730 |
|
Cnemaspis mahsuriae | Malaysia, Kedah, Pulau Langkawi, Gunung Raya |
|
KT250634 |
|
Cnemaspis mcguirei | Malaysia, Perak, Bukit Larut |
|
KM024751 |
|
Cnemaspis narathiwatensis | Malaysia, Perak, Belum-Temengor, Sungai Enam |
|
KM024762 |
|
|
KM024763 | |||
siamensis group | ||||
Cnemaspis adangrawi | Thailand, Satun Province, Mueang Satun District, Ko Adang | ZMKU R 00767 | MK862112 |
|
ZMKU R 00768 | ON843665 | This study | ||
THNHM 28207 | MK862113 |
|
||
ZMKU R 00770 | MK862114 | |||
Thailand, Satun Province, Mueang Satun District, Ko Rawi | ZMKU R 00774 | ON843666 | This study | |
ZMKU R 00775 | MK862115 |
|
||
ZMKU R 00776 | MK862116 | |||
Cnemaspis chanardi | Thailand, Trang Province, Nayong District | ZMKU R 00988 | ON843675 | This study |
ZMKU R 00989 | ON843676 | |||
ZMKU R 00990 | ON843677 | |||
ZMKU R 00991 | ON843678 | |||
Cnemaspis huaseesom | Thailand, Kanchanaburi Province, Sai Yok National Park |
|
KM024733 |
|
|
KM024734 | |||
|
KM024735 | |||
Cnemaspis kamolnorranathi | Thailand, Surat Thani Province, Kanchanadit District, Tai Rom Yen National Park | ZMKU R 00992 | ON843679 | This study |
ZMKU R 00993 | ON843680 | |||
ZMKU R 00994 | ON843681 | |||
ZMKU R 00995 | ON843682 | |||
ZMKU R 00996 | ON843683 | |||
Cnemaspis lineatubercularis | Thailand, Nakhon Si Thammarat Province, Lan Saka District, Wang Mai Pak Waterfall | ZMKU R 00825 | MT112890 |
|
ZMKU R 00828 | MT112891 | |||
ZMKU R 00829 | MT112892 | |||
ZMKU R 00830 | MT112893 | |||
Cnemaspis omari | Thailand, Satun Province, Phuphaphet Cave |
|
KM024780 |
|
Malaysia, Perlis, Perlis State Park |
|
KM024779 | ||
Cnemaspis phangngaensis | Thailand, Phang-nga Province, Mueang Phang-nga District, Khao Chang, Phung Chang Cave |
|
KY091234 |
|
|
KY091235 | |||
Cnemaspis punctatonuchalis | Thailand, Prachaup Khiri Khan Province, Thap Sakae |
|
KY091236 |
|
|
KY091237 | |||
Cnemaspis roticanai | Malaysia, Kedah, Pulau Langkawi, Gunung Raya |
|
KM024829 |
|
|
KM024830 | |||
|
KM024831 | |||
Cnemaspis samui sp. nov. | Thailand, Surat Thani Province, Ko Samui District, Ko Samui, Hin Lad Waterfall | ZMKU R 00966 | ON843667 | This study |
ZMKU R 00967 | ON843668 | |||
ZMKU R 00968 | ON843669 | |||
ZMKU R 00974 | ON843670 | |||
Cnemaspis similan sp. nov. | Thailand, Phang-nga Province, Tai Mueang District, Mu Ko Similan National Park, Ko Similan, Ao Nguang Chang | ZMKU R 00984 | ON843671 | This study |
ZMKU R 00985 | ON843672 | |||
ZMKU R 00986 | ON843673 | |||
ZMKU R 00987 | ON843674 | |||
Cnemaspis selenolagus | Thailand, Ratchaburi Province, Suan Phueng District, Khao Laem Mountain | ZMMU R 16391 | MW051887 |
|
AUP 00767 | MW051888 | |||
Cnemaspis siamensis | Thailand, Chumpon Province, Pathio District |
|
KM024838 |
|
|
KM024839 | |||
ZMKU R 00997 | ON843684 | This study | ||
ZMKU R 00998 | ON843685 | |||
Cnemaspis thachanaensis | Thailand, Surat Thani Province, Tha Chana District, Tham Khao Sonk Hill |
|
KY091239 |
|
|
KY091243 | |||
|
KY091244 | |||
Cnemaspis vandeventeri | Thailand, Ranong Province, Suk Saran District, Naka |
|
KY091238 |
|
Homologous sequences of 68 Cnemaspis and the seven outgroups Cyrtodactylus bokorensis Murdoch, Grismer, Wood, Neang, Poyarkov, Tri, Nazarov, Aowphol, Pauwels, Nguyen & Grismer, 2019, Dixonius melanostictus (Taylor, 1962), Dixonius siamensis (Boulenger, 1898), Gehyra mutilata Wiegmann, 1834, Gekko gecko (Linnaeus, 1758), Hemidactylus frenatus Duméril & Bibron, 1836 and Hemidactylus garnotii Duméril & Bibron, 1836 (following
The ML analysis was implemented using the IQ-TREE web server (
Coloration and pattern in life was determined by examination of digital images taken of living specimens of all possible age classes prior to preservation. Morphological and meristic data were taken by the first author on the left side of preserved specimens for symmetrical characters, when possible, using digital Mitutoyo CD-6” ASX Digimatic Calipers to the nearest 0.1 mm under a Nikon SMZ745 dissecting microscope. Three body-size classes were established by snout-vent length: small size (< 35 mm), medium size (35–40 mm) and large size (> 40 mm). Only adult individuals, as determined by the presence of secondary sexual characteristics such as pore-bearing precloacal scales or hemipenes in males or visible eggs on ventral side of body or enlarged endolymphatic glands in females, were included for morphometric and meristic measurements. A total of sixteen morphological characters was scored following
Meristic characters states of scales and quantitative observations of pattern and structures were evaluated under a Nikon SMZ745 dissecting microscope. Meristic characters taken were modified from
Statistical analyses were used to compare differences in size and shape within the siamensis group, including populations from Ko Samui (N = 18), Ko Similan (N = 4) and the seven described species C. adangrawi (N = 8), C. chanardi (N = 7), C. lineatubercularis (N = 19), C. omari (N = 5), C. phangngaensis (N = 3), C. siamensis (N = 8) and C. thachanaensis (N = 6). Due to lack of available measurements, six species in the siamensis group (C. huaseesom, C. kamolnorranathi, C. punctatonuchalis, C. roticanai, C. selenolagus and C. vandeventeri) were not included in the morphometric analyses. All specimens were assigned to nine putative operation taxonomic units (OTUs) based on the mtDNA results: OTU1 (= Ko Samui population), OTU2 (= Ko Similan population), OTU3 (= C. adangrawi), OTU4 (= C. chanardi), OTU5 (= C. lineatubercularis), OTU6 (= C. omari), OTU7 (= C. phangngaensis), OTU8 (= C. siamensis) and OTU9 (= C. thachanaensis). TL (tail length) was excluded due to their different conditions (e.g., complete, broken, and regenerated). All morphological variables were adjusted for differences in ontogenetic composition by the allometric equation:
Xadj = log(X) – b[log(SVL) – log(SVLmean)]
where Xadj is the corrected value of the morphometric variable; X is the unadjusted value of dependent variable; b is the within-clade coefficient of the linear regression of each original character value (X) against SVL; SVL = snout-vent length; and SVLmean = overall mean of SVL of all nine OTUs (
Univariate analyses were implemented in the Paleontological statistics software (PAST v4.07b;
The aligned dataset contained 1,310 characters of 89 individuals of Cnemaspis and seven individuals of the outgroup species (Fig.
The single best tree from 10,000 Maximum likelihood bootstrap replicates based on 1,310 bp of the mitochondrial NADH dehydrogenase subunit 2 (ND2) and flanking tRNAs from geckos of the genera Cnemaspis, Cyrtodactylus, Dixonius, Gekko, Hemidactylus and Gehyra A shown in full view B relevant clades of Cnemaspis siamensis group in close-up view C map illustrating the type locality of all species in the siamensis group. Nodal support values are ultrafast bootstrap values from maximum likelihood analysis of the same dataset followed by posterior probabilities of Bayesian analysis.
Cnemaspis samples from Ko Samui and Ko Similan represented well-supported independent lineages (100 UFB, 1.0 BPP) and were nested within the siamensis group (Fig.
Mean (min-max) uncorrected pairwise distances (%) within the Cnemaspis siamensis group based on 1,310 bp of the mitochondrial ND2 gene and flanking tRNAs. Number in bold are within species divergence. N = number of individuals.
Species | N | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1. Cnemaspis samui sp. nov. | 4 | 0.55 | ||||||||||||||
(0.00–1.11) | ||||||||||||||||
2. Cnemaspis similan sp. nov. | 4 | 11.50 | 0.00 | |||||||||||||
(11.32–11.56) | (0.00–0.00) | |||||||||||||||
3. C. adangrawi | 9 | 9.32 | 11.12 | 1.58 | ||||||||||||
(8.87–9.68) | (11.08–11.18) | (0.00–3.01) | ||||||||||||||
4. C. chanardi | 4 | 8.92 | 9.40 | 7.80 | 0.26 | |||||||||||
(8.86–9.10) | (9.34–9.58) | (7.52–8.15) | (0.00–0.32) | |||||||||||||
5. C. huaseesom | 3 | 23.00 (22.34–23.67) | 23.19 (22.72–24.10) | 22.47 (22.01–23.27) | 22.63 (22.10–23.58) | 0.31 (0.00–0.78) | ||||||||||
6. C. kamolnorranathi | 5 | 9.55 (9.10–9.73) | 11.73 (11.72–11.80) | 9.08 (8.86–9.44) | 8.38 (8.23–8.54) | 23.48 (23.13–24.10) | 0.08 (0.00–0.24) | |||||||||
7. C. lineatubercularis | 4 | 14.61 (14.10–14.96) | 16.15 (15.92–16.39) | 14.19 (13.63–14.77) | 14.04 (13.63–14.41) | 24.13 (23.02–25.41) | 14.55 (14.23–14.89) | 0.11 (0.00–0.25) | ||||||||
8. C. omari | 2 | 10.98 (10.17–11.81) | 11.42 (10.79–12.06) | 8.20 (6.77–9.40) | 9.36 (8.72–9.96) | 24.74 (24.00–25.60) | 10.81 (10.04–11.65) | 16.15 (15.07–17.04) | 2.36 (0.00–4.72) | |||||||
9. C. phangngaensis | 2 | 9.68 (9.58–9.81) | 8.16 (8.16–8.16) | 9.00 (8.87–9.21) | 7.48 (7.36–7.75) | 21.69 (21.37–22.29) | 10.23 (10.06–10.36) | 15.62 (15.24–16.01) | 10.50 (9.70–11.33) | 0.16 (0.00–0.32) | ||||||
10. C. punctatonuchalis | 2 | 23.53 (21.83–24.93) | 25.24 (23.67–26.82) | 23.19 (21.75–24.53) | 23.74 (22.46–24.93) | 16.70 (15.57–17.59) | 24.34 (23.02–25.62) | 23.72 (21.82–25.62) | 24.79 (22.75–27.82) | 24.21 (22.78–25.65) | 0.75 (0.00–1.5) | |||||
11. C. roticanai | 3 | 10.57 (10.21–10.83) | 11.21 (10.61–11.53) | 7.69 (7.04–8.20) | 8.83 (8.31–9.36) | 24.15 (23.27–24.50) | 10.23 (9.64–10.50) | 14.94 (13.80–15.76) | 8.34 (7.13–8.99) | 9.00 (8.39–9.36) | 23.14 (21.83–24.03) | 0.32 (0.00–0.69) | ||||
12. C. selenolagus | 2 | 22.75 (22.00–23.15) | 22.69 (22.48–22.91) | 21.53 (21.13–21.88) | 21.32 (20.97–21.72) | 16.08 (15.44–17.00) | 22.06 (21.84–22.28) | 22.46 (21.91–22.99) | 23.33 (23.02–23.57) | 21.35 (21.05–21.66) | 15.93 (15.29–17.13) | 22.15 (21.21–22.89) | 0.28 (0.00–0.56) | |||
13. C. siamensis | 4 | 22.04 (20.83–23.59) | 23.21 (21.73–24.88) | 22.20 (21.21–23.39) | 21.70 (20.64–23.11) | 19.28 (18.73–19.59) | 22.27 (21.12–23.83) | 23.00 (22.30–24.64) | 23.30 (21.21–24.58) | 21.68 (20.25–23.29) | 19.49 (18.12–20.70) | 23.26 (21.41–24.87) | 19.10 (18.72–19.55) | 0.55 (0.00–1.74) | ||
14. C. thachanaensis | 3 | 23.10 (22.66–23.29) | 24.27 (24.12–24.50) | 23.43 (22.97–23.89) | 22.59 (22.35–22.89) | 20.98 (20.79–21.11) | 23.04 (22.91–23.19) | 24.08 (23.65–24.58) | 25.03 (24.88–25.24) | 23.44 (23.29–23.71) | 20.83 (20.05–21.57) | 24.79 (24.09–25.32) | 20.73 (20.49–21.00) | 14.31 (13.86–15.21) | 0.67 (0.00–1.74) | |
15. C. vandeventeri | 1 | 26.76 (26.56–26.83) | 27.11 (27.11–27.11) | 26.36 (26.15–26.42) | 26.49 (26.42–26.56) | 20.75 (20.66–20.80) | 27.52 (27.52–27.52 | 25.23 (24.65–25.86) | 27.36 (27.11–27.60) | 26.71 (26.59–26.83) | 20.89 (20.89–20.89) | 27.71 (27.66–27.80) | 23.24 (23.00–23.48) | 13.84 (13.64–14.21) | 17.45 (17.22–17.63) | 0.00 (0.00–0.00) |
Cnemaspis chanardi and C. kamolnorranathi samples from their type localities (Fig.
Univariate analysis of variance (ANOVA) showed significant differences (p < 0.05) in morphometric characters among the Ko Samui population (OTU1), the Ko Similan population (OTU2), and seven congeners (OTU3–OTU9) in the siamensis group (Suppl. material
Pairwise significant difference matrix from 15 size-corrected morphometric measurements of Cnemaspis samui sp. nov. and Cnemaspis similan sp. nov. compared with seven congeners of the Cnemaspis siamensis group (Tukey’s HSD; p< 0.05). Measurement abbreviations are defined in the text.
No. | Species | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
---|---|---|---|---|---|---|---|---|---|
1 | Cnemaspis samui sp. nov. | – | |||||||
2 | Cnemaspis similan sp. nov. | SVL, FL, TBL, AG, HL, HW, IN, IO | – | ||||||
3 | C. adangrawi | TBL, IN, IO | HW, IN, IO | – | |||||
4 | C. chanardi | FL, EL, IN, IO | SVL, TW, FL, HL, HW, IN, IO | FL, EL, IO | – | ||||
5 | C. lineatubercularis | TBL, HL, HW, EL, IN, IO | SVL, TW, FL, TBL, HL, HW, IN, IO | SVL, FL, TBL, HL, HW, EL, IO | TBL, HL, HW | – | |||
6 | C. omari | TW, FL, TBL, HL, HW, EL, IN, IO | SVL, TW, HL, HW, IN, IO | TW, FL, HL HW, ES, EL, IO | FL, HW, IN | FL, TBL, IN | – | ||
7 | C. phangngaensis | TW, TBL, IN | TW, IN | TW, IO | TW, FL | TW, FL, TBL, HL | HL, IN | – | |
8 | C. siamensis | SVL, TW, FL, TBL, HL, HW, ES, IN, IO | SVL, TW, FL, TBL, AG, HL, HW, ES, IN, IO | SVL, TW, FL, TBL, AG, HL, HW, ES, IN | SVL, TW, TBL, AG, HL, HW, ES, EL, IN, IO | SVL, TW, TBL, ES, IN, IO | SVL, FL, TBL, ES | SVL, FL, TBL, HL, ES, IN, IO | – |
9 | C. thachanaensis | SVL, TW, FL, TBL, AG, HL, HW, ES, EN, IN, IO | SVL, FL, TBL, AG, HL, HW, ES, EN, EL, IN | SVL, TW, FL, TBL, AG, HL, HW, ES, EN, IN, IO | SVL, TBL, AG, HL, HW, ES, EN, EL, IN, IO | SVL, TBL, AG, HW, ES, EN, EL, IN, IO | SVL, FL, TBL, AG, ES, EN, EL, IN | SVL, FL, TBL, AG, HL, HW, ES, EN, EL, IO | EN, EL, IN |
Summary of proportions of variance, standard deviation, eigenvalues and factor loadings from the 10 first principal components (PC) of 14 size-adjusted morphometric characters of two new insular species Cnemaspis samui sp. nov., Cnemaspis similan sp. nov. and seven congeners of the Cnemaspis siamensis group including C. adangrawi, C. chanardi, C. lineatubercularis, C. omari, C. phangngaensis, C. siamensis and C. thachanaensis. Values highlighted in bold represent those with the greatest contribution (≥0.30). Measurement abbreviations are defined in the text.
Character | PC1 | PC2 | PC3 | PC4 | PC5 | PC6 | PC7 | PC8 | PC9 | PC10 |
---|---|---|---|---|---|---|---|---|---|---|
Proportion of Variance | 54.6 | 17.2 | 6.2 | 5.7 | 5.1 | 4.3 | 2.3 | 1.3 | 1.0 | 0.8 |
Standard deviation | 2.77 | 1.55 | 0.93 | 0.89 | 0.84 | 0.78 | 0.57 | 0.42 | 0.37 | 0.33 |
eigenvalues | 7.65 | 2.406 | 0.872 | 0.793 | 0.711 | 0.606 | 0.32 | 0.179 | 0.137 | 0.112 |
TW | -0.293 | -0.083 | 0.266 | 0.296 | -0.093 | 0.017 | -0.747 | 0.069 | -0.054 | 0.169 |
FL | -0.263 | -0.125 | -0.375 | -0.362 | 0.414 | -0.207 | -0.317 | -0.01 | 0.005 | 0.374 |
TBL | -0.308 | 0.091 | -0.217 | -0.171 | 0.401 | 0.182 | 0.021 | 0.123 | 0.217 | -0.454 |
AG | -0.302 | 0.233 | -0.04 | -0.132 | -0.093 | 0.247 | 0.069 | -0.708 | -0.358 | 0.163 |
HL | -0.324 | -0.118 | -0.063 | -0.020 | 0.037 | 0.360 | 0.229 | 0.310 | 0.064 | 0.371 |
HW | -0.328 | -0.097 | -0.009 | -0.030 | -0.115 | 0.418 | 0.100 | 0.016 | -0.145 | -0.267 |
HD | -0.321 | -0.073 | 0.332 | 0.211 | -0.114 | 0.066 | 0.175 | 0.170 | -0.108 | 0.095 |
ED | -0.264 | 0.079 | 0.422 | -0.232 | 0.237 | -0.518 | 0.161 | 0.132 | -0.458 | -0.196 |
EE | -0.323 | -0.005 | -0.032 | 0.422 | 0.145 | -0.073 | 0.080 | 0.071 | 0.209 | -0.164 |
ES | -0.304 | 0.191 | 0.011 | 0.198 | -0.086 | -0.370 | 0.098 | -0.408 | 0.532 | -0.027 |
EN | -0.210 | 0.208 | -0.563 | 0.093 | -0.500 | -0.325 | 0.119 | 0.308 | -0.236 | 0.083 |
EL | -0.105 | 0.439 | 0.282 | -0.558 | -0.364 | 0.087 | -0.158 | 0.214 | 0.357 | 0.004 |
IN | -0.096 | -0.565 | 0.172 | -0.231 | -0.137 | -0.155 | 0.325 | -0.085 | 0.254 | 0.292 |
IO | 0.113 | 0.538 | 0.14 | 0.211 | 0.370 | 0.079 | 0.236 | 0.131 | 0.032 | 0.473 |
Multivariate analysis results of principal component analysis (PCA) and discriminant analysis of principal component (DAPC) of 14 morphological variables for nine OTUs (N = 78 individuals) of Cnemaspis in the siamensis group A PCA scatterplot showing morphospatial differentiation among nine species in the siamensis group B DAPC ordination of six PCs and discriminant eigenvalues showing morphospatial variation among nine species in the siamensis group.
The Ko Samui and Ko Similan populations distinctly differed from all congeners in the C. siamensis group that were evaluated based on molecular analyses of mtDNA with high genetic distances, as well in the univariate analyses (ANOVA and Tukey’s HSD pairwise) and the multivariate analyses (PCA and DAPC) of morphology. Based on these corroborating lines of evidence, we hypothesize that the Ko Samui and the Ko Similan populations each represent new species, as described below.
(Fig.
Adult male holotype of Cnemaspis samui sp. nov. (ZMKU R 00974) from Hin Lad Waterfall, Ko Samui, Ang Thong Subdistrict, Ko Samui District, Surat Thani Province, Thailand, in life A dorsolateral view B dorsal view C lateral view D ventral view E precloacal region showing distribution of pore-bearing scales (black arrows). Scale bars in dorsal, lateral, and ventral views: 10 mm.
(Fig.
Cnemaspis samui sp. nov. differs from all other members of the C. siamensis group by having the following combination of characters: (1) SVL 37.0–42.3 mm in adult males (mean 39.90 ± 1.98 mm; N = 15) and 36.4–41.6 mm in adult females (mean 39.75 ± 2.91 mm; N = 3); (2) eight or nine supralabial and infralabial scales; (3) ventral scales keeled (4) 5–8 pore-bearing precloacal scales in males, arranged in a chevron, separated, pore rounded in males; (5) 25–27 paravertebral tubercles, arranged randomly; (6) 4–6 small, subconical spine-like tubercles present on lower flanks; (7) 22–25 subdigital lamellae under 4th toe; (8) enlarged median subcaudal scale row present; (9) ventrolateral caudal tubercles anteriorly present; (10) one or two postcloacal tubercles on lateral surface of hemipenial swellings at the base of tail in males; and (11) gular region, abdomen, limbs and subcaudal region yellowish only in males.
An adult male in good state of preservation; 42.3 mm SVL; head relatively moderate in size (HL/SVL 0.27), narrow (HW/SVL 0.16), flattened (HD/HL 0.39), depressed (HD/SVL 0.11), and head distinct from neck; snout moderate (ES/HL 0.43), in lateral profile slightly concave; loreal region slightly inflated, canthus rostralis not prominent, smoothly rounded; postnasal region constricted medially; scales of rostrum round, juxtaposed, keeled, larger than conical scales on occiput; weak, supraorbital ridges; gular and throat scales granular, keeled and round; shallow frontorostral sulcus; eye large (ED/HL 0.21) with round pupil; orbit with extra-brillar fringe scales slightly largest anteriorly; scales on interorbitals and supercilium slightly keeled; eye to ear distance greater than eyes diameter (EE/ED 1.33); ear opening vertical, oval, taller than wide (EL/HL 0.09); rostral slightly concave; rostral bordered posteriorly by supranasals and internasal; rostral in contact laterally with first supralabials; 9R,L supralabials decreasing in size posteriorly; 8R,L infralabials decreasing in size posteriorly; nostril small, oval, oriented dorsoposteriorly, surrounded posteriorly by small postnasal scales; mental scales enlarged, subtriangular, concave, extending to level of second infralabials, bordered posteriorly by three large postmentals.
Body relatively slender, elongate (AG/SVL 0.42); small, keeled, dorsal scales equal in size throughout body intermixed with several large, keeled, scattered, conical tubercles; 26 paravertebral tubercles randomly arranged; four small, subconical spine-like tubercles on flanks; tubercles present on lower flanks; tubercles extend from occiput to tail; pectoral and abdominal scales keeled, round, flat, slightly larger than dorsal and not larger posteriorly; ventral scales of brachia smooth, raised and juxtaposed; eight separated pore-bearing precloacal scales, arranged in a chevron, with rounded pores; precloacal depression absent; femoral pores absent.
Fore and hind limbs moderately elongate, slender; scales beneath forearm slightly raised, smooth and subimbricate; subtibial scales keeled; palmar scales smooth, flat and subimbricate; digits long, slender, distinctly inflected joint with strong, slightly recurved claws; subdigital lamellae unnotched; lamellae beneath first phalanges wide; lamellae beneath phalanx immediately following inflection granular; lamellae of distal phalanges wide; lamellae beneath inflection large; interdigital webbing absent; enlarged submetatarsal scales on 1st toe present; total subdigital lamellae on fingers I–V: 18-21-22-24-23 (right manus), 18-21-22-24-23 (left manus); fingers increase in length from first to fourth with fifth nearly equal in length as fourth; relative length of fingers IV>V>III>II>I; total subdigital lamellae on toes I–V: 14-20-21-24-23 (right pes), 14-(broken)-21-24-23 (left pes); toes increase in length from first to fourth with fifth nearly equal in length as fourth; relative length of toes IV>V>III>II>I.
Tail complete, entire cylindrical, relatively slender, swollen at the base; tail length (TL) 52.2 mm; tail length longer than snout-vent length (TL/SVL 1.23); subcaudal scales keeled, juxtaposed, larger than dorsal scales of the tail; shallow, middorsal furrow; deeper lateral caudal furrow present; enlarged, transverse caudal tubercles arranged in segmented whorls, encircling tail; enlarged median subcaudal scale row present; caudal tubercles present between upper and lower of lateral furrow; 1R,L enlarged postcloacal tubercle at lateral surface of hemipenial swellings at the base of tail.
(in mm; Table
Descriptive measurements in millimeters and characters of the type series of Cnemaspis samui sp. nov. H = holotype; P = paratype; – = data unavailable or absent; C = complete; B = broken; R = regenerated. Measurement abbreviations are defined in the text.
Characters/Museum Number | ZMKU R 00974 | ZMKU R 00966 | ZMKU R 00967 | ZMKU R 00968 | ZMKU R 00969 | ZMKU R 00970 | ZMKU R 00971 | ZMKU R 00972 | ZMKU R 00973 | ZMKU R 00975 | ZMKU R 00976 | ZMKU R 00977 | ZMKU R 00978 | ZMKU R 00979 | ZMKU R 00983 | ZMKU R 00980 | ZMKU R 00981 | ZMKU R 00982 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Type series | H | P | P | P | P | P | P | P | P | P | P | P | P | P | P | P | P | P |
Sex | Male | Male | Male | Male | Male | Male | Male | Male | Male | Male | Male | Male | Male | Male | Male | Female | Female | Female |
SVL | 42.3 | 40.1 | 41.2 | 40.8 | 37.0 | 38.7 | 41.7 | 41.5 | 40.7 | 41.0 | 40.4 | 35.6 | 40.1 | 36.7 | 40.6 | 36.4 | 41.2 | 41.6 |
Tail | C | C | C | R | B | C | R | C | R | B | B | C | C | C | C | C | R | R |
TL | 52.2 | 50.8 | 57.8 | 56.2 | 44.3 | 48.8 | 51.3 | 59.3 | 40.6 | 28.7 | – | 47.6 | 54.8 | 48.6 | 59.6 | 46.1 | 44.0 | 16.4 |
TW | 4.4 | 3.9 | 3.8 | 4.0 | 3.9 | 4.0 | 4.2 | 4.2 | 4.1 | 4.3 | 4.4 | 3.6 | 4.1 | 3.7 | 4.1 | 3.6 | 4.2 | 3.9 |
FL | 6.5 | 6.3 | 6.3 | 6.2 | 6.2 | 6.1 | 6.3 | 6.2 | 6.1 | 6.5 | 6.8 | 6.2 | 6.2 | 6.0 | 6.1 | 6.2 | 6.2 | 6.1 |
TBL | 7.9 | 7.5 | 7.6 | 7.6 | 7.5 | 7.5 | 7.7 | 7.6 | 7.7 | 7.6 | 7.8 | 7.2 | 7.6 | 6.9 | 7.7 | 7.1 | 7.8 | 7.7 |
AG | 17.9 | 17.7 | 17.7 | 17.7 | 16.1 | 16.1 | 17.7 | 17.6 | 17.7 | 17.7 | 17.6 | 15.5 | 17.6 | 16.1 | 17.8 | 15.2 | 17.9 | 17.9 |
HL | 11.5 | 11.2 | 11.3 | 11.2 | 10.8 | 10.8 | 11.4 | 11.6 | 10.7 | 11.4 | 11.1 | 9.8 | 10.8 | 10.0 | 11.4 | 10.6 | 11.3 | 10.8 |
HW | 6.9 | 6.6 | 6.9 | 6.8 | 6.6 | 6.6 | 6.8 | 6.8 | 6.8 | 6.8 | 6.7 | 6.2 | 6.7 | 6.2 | 6.9 | 6.2 | 6.9 | 6.8 |
HD | 4.5 | 4.2 | 4.3 | 4.2 | 4.1 | 4.1 | 4.4 | 4.3 | 4.3 | 4.4 | 4.4 | 3.8 | 4.3 | 3.9 | 4.4 | 3.8 | 4.4 | 4.4 |
ED | 2.5 | 2.3 | 2.4 | 2.2 | 2.2 | 2.3 | 2.4 | 2.4 | 2.1 | 2.2 | 2.2 | 2.3 | 2.2 | 2.2 | 2.4 | 2.2 | 2.4 | 2.4 |
EE | 3.3 | 3.1 | 3.3 | 3.2 | 3.1 | 3.1 | 3.2 | 3.2 | 3.1 | 3.2 | 3.2 | 2.9 | 3.2 | 3.0 | 3.2 | 2.9 | 3.2 | 3.2 |
ES | 5.0 | 4.9 | 4.9 | 4.9 | 4.5 | 4.6 | 4.8 | 4.8 | 4.7 | 4.9 | 4.9 | 4.6 | 4.9 | 4.7 | 4.8 | 4.5 | 4.9 | 4.9 |
EN | 4.0 | 3.7 | 3.7 | 3.7 | 3.8 | 3.7 | 4.0 | 3.9 | 3.7 | 3.8 | 3.7 | 3.4 | 3.6 | 3.5 | 3.9 | 3.5 | 4.0 | 3.9 |
EL | 1.0 | 0.9 | 0.8 | 0.8 | 0.9 | 0.7 | 0.9 | 1.0 | 1.0 | 0.9 | 0.9 | 0.9 | 0.8 | 0.9 | 0.9 | 0.9 | 0.9 | 0.8 |
IO | 3.3 | 3.1 | 3.3 | 3.2 | 3.0 | 3.2 | 3.2 | 3.1 | 3.1 | 3.2 | 3.1 | 2.8 | 3.1 | 2.8 | 3.2 | 2.8 | 3.3 | 3.3 |
IN | 1.1 | 1.0 | 1.1 | 1.0 | 0.9 | 1.0 | 1.1 | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 | 0.9 | 1.0 | 1.1 | 1.0 | 1.0 | 1.1 |
Supralabial scales | 9 | 9 | 9 | 9 | 9 | 9 | 8 | 9 | 8 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 |
Infralabial scales | 8 | 9 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 9 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 8 |
No. of precloacal pores | 8 | 7 | 8 | 5 | 6 | 8 | 7 | 8 | 7 | 6 | 7 | 8 | 7 | 5 | 7 | – | – | – |
Precloacal pore continuous (1) or separated (0) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | – | – | – |
Precloacal pores elongate (1) or round (0) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | – | – | – |
No. of paravertebral tubercles | 26 | 26 | 25 | 27 | 26 | 27 | 27 | 26 | 27 | 25 | 27 | 26 | 25 | 27 | 27 | 27 | 27 | 26 |
Tubercles linearly arranged (1) or more random (0) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Tubercles present (1) or absent (0) on lower flanks | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
No. of 4th toe lamellae | 24 | 23 | 25 | 25 | 25 | 25 | 23 | 25 | 24 | 24 | 25 | 22 | 25 | 25 | 25 | 24 | 24 | 25 |
Lateral caudal furrows present (1) or absent (0) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Pectoral scales keeled (1) or smooth (0) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Ventral scales on thigh keeled (1) or smooth (0) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Subcaudal keeled (1) or smooth (0) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Subtibial scales keeled (1) or smooth (0) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Enlarged median subcaudal scale row (1) or not (0) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Caudal tubercles restricted to the single paravertebral row on each side (1) or not (0) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
(Figs
(Figs
Most paratypes closely resemble the holotype in all aspect of pattern and coloration. Morphometric and meristic variation within the type series is presented in Table
Cnemaspis samui sp. nov. is currently only known from the type locality at Hin Lad Waterfall (9°31.151'N, 99°57.598'E; 150 m a.s.l.; Fig.
The type locality is surrounded by lowland evergreen forest with granitic rocky outcrops along Lipa Yai Canal in the western part of Ko Samui. All specimens of C. samui sp. nov. were found along rocky stream outcrops of Hin Lad Waterfall during the day (1435–1752 h) and night (1800–1845 h) with air temperatures of 26.2–30.1 °C and relative humidity of 76.9–92.7%. Their microhabitats in rocky boulders were relatively dry and cool. The male holotype was found at night (1845 h) perched upside down on an overhanging surface of a granitic rock boulder near a stream. Most specimens were found on or within deep cracks or crevices of boulders, or in shaded areas of the boulder near a stream, except that ZMKU R 00969 was found on a tree trunk and ZMKU R 00977 was found in a soil hole at the base of a boulder. Two gravid females ZMKU R 00981–00982 were carrying one or two eggs in July 2018. Some juveniles (not collected) were mostly found perched on vegetation (e.g., log, vine, tree root). Cnemaspis samui sp. nov. is assumed to be a diurnal rock-dwelling species. During the day, geckos were found to be active, wary and fast-moving. They were most often observed clinging upside down to the undersides of rock boulders and within deep crevices. When disturbed, they would quickly move to deeper cover and hide in the shaded area between boulder and the ground. At night, they were found to be inactive, slow moving, sheltered in crevices or cracks on rock walls, or sleeping on vegetation near rock boulders, making them easier to approach than during the day. During field surveys, the larger nocturnal gekkonid Cyrtodactylus zebraicus (Taylor, 1962) was found in sympatry on the ground and vegetation near a stream.
The specific epithet samui is a noun in apposition and refers to the type locality of Ko Samui.
Cnemaspis samui sp. nov. is distinguished from all members of the siamensis group (C. adangrawi, C. chanardi, C. huaseesom, C. kamolnorranathi, C. lineatubercularis, C. omari, C. phangngaensis, C. punctatonuchalis, C. selenolagus, C. siamensis, C. thachanaensis, and C. vandeventeri) by having a unique combination of morphological characteristics (Table
Meristic character state and color pattern of species in the Cnemaspis siamensis group. SVL taken in millimeters and measurement abbreviations are defined in the text. – = data unavailable, w = weak.
Characters / Species | Cnemaspis samui sp. nov. | Cnemaspis similan sp. nov. | C. adangrawi | C. chanardi | C. huaseesom | C. kamolnorranathi | C. lineatubercularis | C. omari | C. phangngaensis | C. punctatonuchalis | C. selenolagus | C. siamensis | C. thachanaensis | C. vandeventeri |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Sample size | 18 | 4 | 15 | 25 | 5 | 4 | 19 | 8 | 2 | 5 | 2 | 12 | 6 | 3 |
Maximum SVL | 42.3 | 48.1 | 44.9 | 40.9 | 43.5 | 37.8 | 41.8 | 41.3 | 42.0 | 49.6 | 36.2 | 39.7 | 39.0 | 44.7 |
Supralabial scales | 8 or 9 | 8 or 9 | 10 | 8–10 | 7–10 | 8 or 9 | 9 | 8 or 9 | 10 | 8 | 10 or 11 | 8 or 9 | 10 or 11 | 8 or 9 |
Infralabial scales | 8 or 9 | 7 or 8 | 9 | 8 | 6–9 | 7 or 8 | 9 | 7 or 8 | 10 | 7 or 8 | 10 | 6–8 | 9–11 | 7–9 |
No. of pore-bearing precloacal scales | 5–8 | 1 | 6–8 | 6–8 | 5–8 | 6 or 7 | 4–7 | 3–6 | 4 | 0 | 6 or 7 | 0 | 0 | 4 |
Pore-bearing precloacal scales row continuous (1) or separated (0) | 0 | – | 0 | 0 | 1 | 1 | 0 | 0 | 1 | – | 1 | – | – | 0 |
Pore-bearing precloacal scales elongate (1) or round (0) shapes | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | – | 1 | – | – | 0 |
No. of paravertebral tubercles | 25–27 | 24 or 25 | 23–25 | 22–25 | 18–24 | 19–24 | 19–21 | 22–29 | 22 | 24–27 | 16–18 | 19–25 | 15–19 | 25–29 |
Paravertebral tubercles linearly arranged (1) or more random (0) | 0 | 0 | 0 | 0 | w or 0 | w | 1 | w or 0 | 1 | w | 0 | 0 | 1 | 0 |
Tubercles present (1) or absent (0) on lower flanks | 1 | 1 | 0 | 1 | 1 | 1 | 1 | w or 1 | 0 | 1 | 0 | 1 | 1 | 1 |
No. of 4th toe lamellae | 22–25 | 23 or 24 | 26–28 | 26–29 | 21–31 | 24–28 | 27–29 | 25–28 | 29 | 29–31 | 22 | 24–26 | 24 | 24–28 |
Ventral scales keeled (1) or smooth (0) | 1 | 1 | 1 | 1 | 0 | w or 0 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 |
Subcaudal scales keeled (1) or smooth (0) | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 |
Single median row of keeled subcaudals (1) or smooth (0) scales | 1 | 1 | 1 | 0 | 0 | w | 1 | 0 | 1 | 0 | – | 0 | 1 | w |
Enlarged median subcaudal scales row (1) or not (0) | 1 | 0 | 0 | 1 | 0 | w | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 1 |
Caudal tubercles restricted to a single paravertebral row on each side (1) or not (0) | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | – | 0 | 1 | 0 |
Ventrolateral caudal tubercles anteriorly present (1) or not (0) | 1 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 1 | 1 | 0 | 0 | 1 | 0 |
No. of postcloacal tubercles in males | 1 or 2 | 2 | 1 | 1 | 1 or 2 | 1 or 2 | 1 | 1 | 2 | 1–3 | 2 | 1 or 2 | 0 | 1–3 |
Subtibial scales keeled (1) or smooth (0) | 1 | 1 | 1 | 1 | 0 | 0 or 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 |
Yellow coloration in the subcaudal region present (1) or not (0) | 1 | 0 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 |
Ventral pattern sexually dimorphic present (1) or not (0) | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | – | 1 | 1 | 1 |
Cnemaspis samui sp. nov. is distinguished from C. adangrawi
Cnemaspis samui sp. nov. is distinguished from C. chanardi
Cnemaspis samui sp. nov. is distinguished from C. huaseesom
Cnemaspis samui sp. nov. is distinguished from C. kamolnorranathi
Cnemaspis samui sp. nov. is distinguished from C. lineatubercularis
Cnemaspis samui sp. nov. is distinguished from C. omari
Cnemaspis samui sp. nov. is distinguished from C. phangngaensis
Cnemaspis samui sp. nov. is distinguished from C. punctatonuchalis
Cnemaspis samui sp. nov. is distinguished from C. selenolagus
Cnemaspis samui sp. nov. is distinguished from C. siamensis (Smith, 1925) by having maximum SVL 42.3 mm (vs. 39.7 mm); pore-bearing precloacal scales present (vs. absent); single median row of subcaudals keeled (vs. smooth); ventrolateral caudal tubercles anteriorly present (vs. absent); and yellow coloration in the subcaudal region present (vs. absent).
Cnemaspis samui sp. nov. is distinguished from C. thachanaensis
Cnemaspis samui sp. nov. is distinguished from C. vandeventeri
(Fig.
Adult male holotype of Cnemaspis similan sp. nov. (ZMKU R 00984) from Ao Nguang Chang Bay, Ko Similan, Mu Ko Similan National Park, Lam Kaen Subdistrict, Thai Mueang District, Phang-nga Province, Thailand, in life A dorsolateral view B dorsal view C lateral view D ventral view E precloacal region showing distribution of pore-bearing scale (black arrow). Scale bars in dorsal, lateral, and ventral views: 10 mm.
(Fig.
Cnemaspis similan sp. nov. can be distinguished from all other members of the C. siamensis group by having the following combination of characters: (1) SVL of 47.6 mm in adult male and 38.6–48.1 mm (mean 43.6 ± 4.8 mm, N = 3) in adult females; (2) eight or nine supralabial and seven or eight infralabial scales; (3) ventral scales keeled (4) one pore-bearing precloacal scale, pore rounded in male; (5) 24 or 25 paravertebral tubercles, arranged randomly; (6) five small, elongated, spine-like tubercles on lower flanks; (7) 23 or 24 subdigital lamellae under the 4th toe; (8) no enlarged median subcaudal scale row; (9) ventrolateral caudal tubercles anteriorly present; (10) two postcloacal tubercles on lateral surface of hemipenial swellings at tail base in male; (11) sexual dimorphism in dorsal and ventral patterns; and (12) pale yellow reticulum on head, neck, flanks, belly and limbs only in male.
An adult male in good state of preservation; 47.6 mm SVL; head moderate in size (HL/SVL 0.26), narrow (HW/SVL 0.16), flattened (HD/HL 0.39) and head distinct from neck; snout moderate (ES/HL 0.43), in lateral profile concave; loreal region marginally inflated, canthus rostralis nearly absent; postnasal region concave medially; scales of rostrum smooth, raised, larger than conical scales on occiput; weak and faint supraorbital ridges; gular scales granular, keeled, rounded, juxtaposed; throat scales granular, keeled, flat, subimbricate; shallow frontonasal sulcus; eye large (ED/HL 0.19); pupil round; extra-brillar fringe scales small in general but slightly larger anteriorly; scales on interorbitals and supercilium keeled; eye to ear distance greater than eyes diameter (EE/ED 1.50); ear opening elongate, much taller than wide (EL/HL 0.08); rostral concave dorsally; rostral bordered posteriorly by supranasals and laterally by first supralabials; 8R,L supralabials decreasing in size posteriorly; 7R,L infralabials decreasing in size posteriorly; nostril small, elliptical, oriented dorsoposteriorly, bordered posteriorly by small postnasal scales; mental scales large, triangular, flat, extending to level of second infralabial scales, bordered posteriorly by three large postmental scales.
Body robust, not elongate (AG/SVL 0.41); small, raised, keeled, dorsal scales equal in size throughout body intermixed with numerous large, keeled, multicarinate tubercles; 24 paravertebral tubercles randomly arranged; five small, elongated, spine-like tubercles on flanks; tubercles present on lower flanks; tubercles extend from occiput to tail; pectoral and abdominal scales keeled, round, flat, imbricate; abdominal scales larger than pectoral and dorsal scales; ventral scales of brachia smooth, raised and juxtaposed; one pore-bearing precloacal scale, with rounded pore; precloacal depression absent; femoral pores absent.
Fore and hind limbs moderately long, slender; scales beneath forearm slightly raised, smooth and subimbricate; subtibial scales keeled; palmar scales keeled, flat and subimbricate; digits long, slender with inflected joint; claws slightly recurved; subdigital lamellae unnotched; lamellae beneath first phalanges wide; lamellae beneath phalanx immediately following inflection granular; lamellae of distal phalanges wide; lamellae beneath inflection large; interdigital webbing generally absent; enlarged submetatarsal scales on 1st toe present; total subdigital lamellae on fingers I–V: 15-21-22-24-23 (right manus), 15-21-23-24-23 (left manus); fingers increase in length from first to fourth with fifth nearly equal in length as fourth; relative length of fingers IV>V>III>II>I; total subdigital lamellae on toes I–V: 17-20-22-24-23 (right pes), 17-19-22-24-23 (left pes); toes increase in length from first to fourth with fifth nearly equal in length as fourth; relative length of toes IV>V>III>II>I.
Tail regenerated, subcylindrical, relatively swollen at the base; tail length (TL) 49.6 mm; tail length longer than head and body (TL/SVL 1.04); dorsal and ventral scales at the tail base similar in size on mid-body dorsum; subcaudal scales keeled, juxtaposed, larger than dorsal scale of the tail size; shallow, middorsal furrow; lateral caudal furrow present; enlarged, transverse caudal tubercles arranged in segmented whorls, encircling tail; enlarged median subcaudal scale row absent; caudal tubercles present between upper and lower of lateral furrow; rest of the tail regenerated, slightly keeled, imbricate scales with no enlarged tubercles; scales on ventral aspect of the regenerated tail marginally larger in size than mid-body ventrals; 2R,L enlarge postcloacal tubercle at lateral surface of hemipenial swellings at the tail base.
(in mm; Table
Descriptive measurements in millimeters and characters of the type series of Cnemaspis similan sp. nov. H = holotype; P = paratype; – = data unavailable or absent; C = complete; R = regenerated. Measurement abbreviations are defined in the text.
Characters / Museum number | ZMKU R 00984 | ZMKU R 00985 | ZMKU R 00986 | ZMKU R 00987 |
---|---|---|---|---|
Sex | Male | Female | Female | Female |
Type series | H | P | P | P |
SVL | 47.6 | 48.1 | 38.6 | 44.2 |
Tail | R | R | R | C |
TL | 49.6 | 43.2 | 37.6 | 58.2 |
TW | 4.6 | 4.6 | 4.1 | 4.4 |
FL | 6.8 | 6.9 | 6.2 | 6.6 |
TBL | 8.6 | 8.8 | 7.5 | 8.4 |
AG | 19.6 | 19.8 | 16.6 | 19.4 |
HL | 12.4 | 12.6 | 10.4 | 12.1 |
HW | 7.8 | 7.9 | 6.5 | 7.7 |
HD | 4.8 | 4.9 | 4.1 | 4.6 |
ED | 2.4 | 2.4 | 2.1 | 2.3 |
EE | 3.6 | 3.7 | 3.0 | 3.4 |
ES | 5.3 | 5.4 | 4.3 | 4.9 |
EN | 4.0 | 4.1 | 3.4 | 3.7 |
EL | 1.0 | 1.0 | 0.9 | 1.0 |
IO | 3.1 | 3.2 | 2.6 | 2.6 |
IN | 1.1 | 1.1 | 0.9 | 1.0 |
Supralabial scales | 8 | 9 | 9 | 9 |
Infralabial scales | 7 | 8 | 8 | 8 |
No. of precloacal pores | 1 | – | – | – |
Precloacal pore continuous (1) or separated (0) | – | – | – | – |
Precloacal pores elongate (1) or round (0) | 0 | – | – | – |
No. of paravertebral tubercles | 24 | 25 | 25 | 24 |
Tubercles linearly arranged (1) or more random (0) | 0 | 0 | 0 | 0 |
Tubercles present (1) or absent (0) on lower flanks | 1 | 1 | 1 | 1 |
No. of 4th toe lamellae | 24 | 24 | 23 | 23 |
Lateral caudal furrows present (1) or absent (0) | 1 | 1 | 1 | 1 |
Pectoral scales keeled (1) or smooth (0) | 1 | 1 | 1 | 1 |
Ventral scales on thigh keeled (1) or smooth (0) | 1 | 1 | 1 | 1 |
Subcaudal keeled (1) or smooth (0) | 1 | 1 | 1 | 1 |
Subtibial scales keeled (1) or smooth (0) | 1 | 1 | 1 | 1 |
Enlarged median subcaudal scale row (1) or not (0) | 0 | 0 | 0 | 0 |
Caudal tubercles restricted to the single paravertebral row on each side (1) or not (0) | 1 | 1 | 1 | 1 |
(Figs
(Figs
Adult male holotype of Cnemaspis similan sp. nov. (ZMKU R 00984) from Ao Nguang Chang Bay, Ko Similan, Mu Ko Similan National Park, Lam Kaen Subdistrict, Thai Mueang District, Phang-nga Province, Thailand, in preservative A dorsal view B ventral view C dorsal view of trunk. Scale bar in dorsal and ventral views: 10 mm.
Due to having only a single adult male (N = 1), variation in adult males is currently unknown. Most paratypes approximate the holotype in general features of body pattern and coloration. Adult females lack pore-bearing precloacal scale. Pale yellowish markings in head, neck, limbs, flanks and caudal regions were also absent in adult females. Three adult females have paler dorsal markings than the holotype. ZMKU R 00985 and ZMKU R 00986 have regenerated tails of uniform tan colored. ZMKU R 00985 has a large calcium sac on each side of the neck. ZMKU R 00985 has also broken left 4th pes.
Cnemaspis similan sp. nov. is known only from the type locality at Ao Nguang Chang Bay (8°64.840'N, 97°64.834'E; 13 m a.s.l.; Fig.
Habitats of Cnemaspis similan sp. nov. at the type locality A mixed evergreen forest with shrub and beach forests B microhabitat of holotype on tree near granitic rock boulder C microhabitat of paratypes in granitic rock boulder D microhabitat of paratypes in rock wall with vegetations (tree trunk, root or vine) of Ao Nguang Chang Bay, Ko Similan, Mu Ko Similan National Park, Lam Kaen Subdistrict, Thai Mueang District, Phang-nga Province, Thailand.
The type locality is dominated by mixed evergreen forest with shrub and beach forests. Ao Nguang Chang Bay is located at the southern part of the largest island, Ko Similan (= Ko Pad). All specimens of C. similan sp. nov. were found in granitic rocky outcrops near Ao Nguang Chang Bay during the day (1542 h) and night (2023–2049 h) with an air temperature of 28.4 °C and relative humidity of 86%. Granitic boulder surfaces appeared to be relatively dry and cool. The male holotype was found during the night (2023 h) on a tree near a boulder. Most paratypes (ZMKU R 00985–00986) were found during the day time on vegetation (tree trunks, roots, or vines) except ZMKU R 00987, which was perched on a rock wall. Cnemaspis similan sp. nov. seems to be a diurnal rock-dwelling species. During the day, geckos were generally active, quite wary and quickly retreated when approached or disturbed. At night, geckos were found inactive or sleeping on vegetation near crevices or cracks of rock boulder as high as 2 m above the ground. They were often found clinging upside down to the underside of rock boulder overhang. During field surveys, the larger, nocturnal gekkonid Cyrtodactylus oldhami (Theobald, 1876) was found in sympatry on the ground and vegetation near boulders.
The specific epithet similan is a noun in apposition and refers to the type locality of Ko Similan.
Cnemaspis similan sp. nov. can be distinguished from 13 congeners of the siamensis group (C. adangrawi, C. chanardi, C. huaseesom, C. kamolnorranathi, C. lineatubercularis, C. omari, C. phangngaensis, C. punctatonuchalis, C. samui sp. nov., C. selenolagus, C. siamensis, C. thachanaensis, and C. vandeventeri) by having a unique combination of morphological characters (Table
Cnemaspis similan sp. nov. is distinguished from C. adangrawi
Cnemaspis similan sp. nov. is distinguished from C. chanardi
Cnemaspis similan sp. nov. is distinguished from C. huaseesom
Cnemaspis similan sp. nov. is distinguished from C. kamolnorranathi
Cnemaspis similan sp. nov. is distinguished from C. lineatubercularis
Cnemaspis similan sp. nov. is distinguished from C. omari
Cnemaspis similan sp. nov. is distinguished from C. phangngaensis
Cnemaspis similan sp. nov. is distinguished from C. punctatonuchalis
Cnemaspis similan sp. nov. is distinguished from C. samui sp. nov. by having maximum SVL 48.1 mm (vs. 42.3 mm); one pore-bearing precloacal scale (vs. 5–8 scales); enlarged median subcaudal scales row absent (vs. present); and yellow coloration in the subcaudal region absent (vs. present).
Cnemaspis similan sp. nov. is distinguished from C. selenolagus
Cnemaspis similan sp. nov. is distinguished from C. siamensis (Smith, 1925) by having maximum SVL 48.1 mm (vs. 39.7 mm); one pore-bearing precloacal scale (vs. absent); single median row of subcaudal keeled (vs. smooth); enlarged median subcaudal scales row absent (vs. present); and ventrolateral caudal tubercles anteriorly present (vs. absent).
Cnemaspis similan sp. nov. is distinguished from C. thachanaensis
Cnemaspis similan sp. nov. is distinguished from C. vandeventeri
Historically, most Thai Cnemaspis were known from areas of limestone karsts and granitic rock formations on the mainland in western, eastern and southern Thailand (
This study revealed two unrecognized species of Cnemaspis in granitic areas of southern Thailand, suggesting that additional sampling might reveal more species in this region. Additionally, the phylogenetic analyses of the siamensis group confirmed that C. chanardi and C. kamolnorranathi are strongly supported members of the siamensis group. Previously,
This work was financially supported by Srinakharinwirot University Research Grant (No. 596/2564) and the Thailand Research Fund (DBG6080010). AR and AA were supported by Kasetsart University Research and Development Institute (KURDI), Office of the Permanent Secretary, Ministry of Higher Education, Science, Research and Innovation (No. RGNS 64-038) and the Department of Zoology, Faculty of Science, Kasetsart University. Department of National Parks, Wildlife and Plant Conservation, Thailand provided permission to conduct the research (Permit no.0907.4/20800 and 0907.4/28401). This research was approved by the Institutional Animal Care and Use Committee of Faculty of Science, Kasetsart University (project no. ACKU61-SCI-008). We thank Ruamsilp Manajongprasert (Mu Ko Similan National Park) for facilitating the fieldwork. Piyawan Puanprapai and Akrachai Aksornneam assisted with fieldwork. Lee Grismer and an anonymous reviewer improved the manuscript.
Cnemaspis adangrawi: Thailand, Satun Province, Mueang Satun District, Ko Adang: ZMKU R 00767 (male holotype), ZMKU R 00769–70, THNHM 28206–09 (6 males), ZMKU R 00768, ZMKU R 00771 (2 females); Thailand, Satun Province, Mueang Satun District, Ko Rawi: ZMKU R 00773, ZMKU R 00775, THNHM 28210 (3 adult males), ZMKU R 00774, THNHM 28211 (2 females).
Cnemaspis chanardi: Thailand, Trang Province, Nayong District, Ban Chong: THNHM 06983 (male holotype); Krabi Province, Klong Thom District: THNHM 012439–40 (males); Mueang Krabi District: THNHM 012436–37 (males), THNHM 012438 (female); Nakhon Si Thammarat Province, Tha Sala District: THNHM 020992 (male); Lansaka district: THNHM 014111 (immature male); Noppitam district: THNHM 013838 (male), THNHM 010705 (male); Surat Thani Province, Mu Ko Ang Thong, Mueang Surat Thani District: THNHM 016074 (female).
Cnemaspis huaseesom: Thailand, Kanchanaburi Province, Sai Yok District, Sai Yok National Park: THNHM 15909 (male holotype).
Cnemaspis lineatubercularis: Thailand, Nakhon Si Thammarat Province, Lan Saka District, Wang Mai Pak Waterfall: ZMKU R 00828 (male holotype); ZMKU R 00821–31 (males); THNHM 28694–95 (males); ZMKU R 00826 (female); THNHM 28696–97 (females); ZMKU R 00832–35 (females).
Cnemaspis niyomwanae: Thailand, Trang Province, Palean District, Thum Khao Ting: THNHM 15909 (female holotype).
Cnemaspis punctatonuchalis: Thailand, Prachuap Khiri Khan Province, Thap Sakae District, Huay Yang National Park: THNHM 02001 (male holotype).
Cnemaspis siamensis: Thailand, Nakhon Si Thammarat Province, Lan saka District: THNHM 013828 (male); Tha Sala District: THNHM 018265 (male); Chumpon Province, Mueang Chumpon District: THNHM 0372 (male); Phato District: THNHM 01086 (male); Surat Thani Province, Vibhawadee District: THNHM 01084 (female); Mu Ko Ang Thong, Mueang Surat Thani District: THNHM 015624 (female).
Cnemaspis vandeventeri: Thailand, Ranong Province, Kapur District, Klong Naka: THNHM 08261 (male holotype), THNHM 08260 (female).
Table S1
Data type: excel file
Explanation note: Significant p-values of the ANOVA analyses (Tukey’s HSD; p<0.05) from 15 size-corrected morphometric measurements of nine OTUs of Cnemaspis siamensis species group. HD, ED and EE were not significantly different from one another. Measurement abbreviations are defined in the material and methods.