Integrative taxonomy of the Asian skinks Sphenomorphus stellatus (Boulenger, 1900) and S. praesignis (Boulenger, 1900), with the resurrection of S. annamiticus (Boettger, 1901) and the description of a new species from Cambodia

Abstract

Molecular phylogenetic analyses of the sister species Sphenomorphus stellatus and S. praesignis based on the mitochondrial genes 12S and 16S rRNA recover the former as paraphyletic with respect to the latter in that a specimen of S. stellatus from the type locality in Peninsular Malaysia is more closely related to S. praesignis than to Indochinese populations of S. stellatus. Furthermore, the phylogeny indicates that the Indochinese populations represent two species, thus resulting in four major lineages within this clade. These relationships are consistent with multivariate and univariate analyses of morphological and discrete color pattern data which statistically define and diagnose the four lineages and together with the molecular data, provide the foundation for robust, testable, species-level hypotheses. As such, S. stellatus is herein restricted to Peninsular Malaysia; S. annamiticus is resurrected for the circum-continental populations ranging through southeastern Thailand, southern Cambodia, and southern Vietnam; a new species—S. preylangensis sp. nov.—is described from an isolated mountain, Phnom Chi, from the Prey Lang Wildlife Sanctuary in central Cambodia; and the taxonomy of S. praesignis remains unchanged. The description of S. preylangensis sp. nov. underscores the necessity to conserve this remnant of lowland evergreen rainforest in the Prey Lang Wildlife Sanctuary.

Full text

ZOOTAXA
ISSN 1175-5326 (print edition)
ISSN 1175-5334 (online edition)
Accepted by A. Datta-Roy: 9 Sept. 2019; published: 9 Oct. 2019 381
Zootaxa 4683 (3): 381–411
https://www.mapress.com/j/zt/
Copyright © 2019 Magnolia Press Article
https://doi.org/10.11646/zootaxa.4683.3.4
http://zoobank.org/urn:lsid:zoobank.org:pub:E32D67E8-8D2B-43FF-9CD7-0D6507C79F99
Integrative taxonomy of the Asian skinks Sphenomorphus stellatus
(Boulenger, 1900) and S. praesignis (Boulenger, 1900)
with the resurrection of S. annamiticus (Boettger, 1901)
and the description of a new species from Cambodia
L. LEE GRISMER1,9, PERRY L. WOOD, JR.2, EVAN S. H. QUAH1,3, SHAHRUL ANUAR3,
NIKOLAY A. POYARKOV4,5, NEANG THY6, NIKOLAI L. ORLOV7,
PANUPONG THAMMACHOTI8 & HUN SEIHA6
1Herpetology Laboratory, Department of Biology, La Sierra University, 4500 Riverwalk Parkway, Riverside, California 92515, USA
2Department of Biological Sciences & Museum of Natural History, Auburn University, Auburn, Alabama 36849, USA
E-mail: perryleewoodjr@gmail.com
3Institute of Tropical Biodiversity and Sustainable Development, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Tereng-
ganu, Malaysia
4Faculty of Biology, Department of Vertebrate Zoology, Moscow State University, Moscow, Russia. E-mail: n.poyarkov@gmail.com
5Laboratory of Tropical Ecology, Joint Russian-Vietnamese Tropical Research and Technological Center, Hanoi, Vietnam
6Wild Earth Allies, 77a, St. Betong, Bayap Village, Sangkat Phom Penh Thmei, Khan Sen Sok, Phnom Penh, Cambodia.
E-mail: thyneang9@gmail.com
7Zoological Institute, Russian Academy of Sciences, Universitietskaya nab., 1, St. Petersburg 199034, Russia.
E-mail: azemiops@zin.ru
8Department of Biology, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok, Thailand 10330
E-mail: Panupong.Th@chula.ac.th
9Corresponding author. E-mail: lgrismer@lasierra.edu
Abstract
Molecular phylogenetic analyses of the sister species Sphenomorphus stellatus and S. praesignis based on the mitochondrial
genes 12S and 16S rRNA recover the former as paraphyletic with respect to the latter in that a specimen of S. stellatus
from the type locality in Peninsular Malaysia is more closely related to S. praesignis than to Indochinese populations of
S. stellatus. Furthermore, the phylogeny indicates that the Indochinese populations represent two species, thus resulting
in four major lineages within this clade. These relationships are consistent with multivariate and univariate analyses
of morphological and discrete color pattern data which statistically define and diagnose the four lineages and together
with the molecular data, provide the foundation for robust, testable, species-level hypotheses. As such, S. stellatus is
herein restricted to Peninsular Malaysia; S. annamiticus is resurrected for the circum-continental populations ranging
through southeastern Thailand, southern Cambodia, and southern Vietnam; a new species—S. preylangensis sp. nov.—is
described from an isolated mountain, Phnom Chi, from the Prey Lang Wildlife Sanctuary in central Cambodia; and the
taxonomy of S. praesignis remains unchanged. The description of S. preylangensis sp. nov. underscores the necessity to
conserve this remnant of lowland evergreen rainforest in the Prey Lang Wildlife Sanctuary.
Key words: Phylogenetic systematics, Indochina, Peninsular Malaysia, Cambodia, Vietnam, Scincidae, Prey Lang
Wildlife Sanctuary
Introduction
Skinks compose a widespread cosmopolitan group of at least 1669 species and are the most speciose lizard family
in the world with Asia and Australia being the major centers of skink diversity (Uetz et al. 2019). Ongoing integra-
tive and traditional taxonomic analyses of Indochinese and Sundaic skinks are beginning to reveal that many of the
more widespread lineages are far more diverse than their previous taxonomies had indicated (e.g. Grismer & Quah
2015; Grismer et al. 2017, 2018, 2019a; Karin et al. 2018; Siler et al. 2018; Freitas et al. 2019; Sumarli et al. 2016;

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382 · Zootaxa 4683 (3) © 2019 Magnolia Press
Linkem 2013; Neang et al. 2018; Poyarkov et al. 2019). Two species that have thus far evaded taxonomic scrutiny
are Sphenomorphus stellatus (Boulnenger, 1900) and S. praesignis (Boulenger, 1900). Sphenomorphus stellatus as
currently recognized, ranges throughout much of Indochina from southern Vietnam, southern Cambodia and south-
eastern Thailand to Peninsular Malaysia (Nguyen et al. 2009; Grismer 2011; Grismer et al. 2008; Taylor 1963) and S.
praesignis is endemic to the Thai-Malay Peninsula south of the Isthmus of Kra (Grismer 2011; Fig. 1). To date, there
have been no taxonomic revisions of either species and the only well-supported phylogeny including them both is an
unpublished dissertation (Linkem 2013) where they were recovered as sister taxa. However, Linkem’s two samples
of S. stellatus were from Indochina and not the type locality of Bukit Larut, in Peninsular Malaysia from which only
the three syntypes collected prior to 1900 are known. We collected an adult female (LSUHC 13483) from the type
locality and compared it to the type material (BMNH 1946.8.3.26, 1946.8.17.10; the third specimen, from 4000 ft,
collected A.L. Butler, and presumably lodged in the Selangor Museum, could not be located) and unreported speci-
mens from Cameron and Genting Highlands, Peninsular Malaysia (MCZ 39283 and CM 65530, respectively) as
well as 18 additional specimens from Thailand, Cambodia, and Vietnam (Fig. 1). Molecular phylogenetic analyses
using the mitochondrial genes 12S and 16S rRNA of a subset of eight S. stellatus from throughout its range and 13
samples of S. praesignis from throughout Peninsular Malaysia recovered S. stellatus as paraphyletic with respect
to S. praesignis in that the Peninsular Malaysian S. stellatus were the sister species of S. praesignis and not their
putatively conspecific Indochinese populations. The analyses also revealed that the Indochinese samples contained
more than one species, one of which was undescribed. Therefore, in order to construct a taxonomy that is consistent
with the evolutionary history of these populations, we here present a phylogenetic taxonomy based on molecular
phylogenetic, morphological, and color pattern data.
Materials and methods
Species delimitation. The general lineage concept (GLC: de Queiroz 2007) adopted herein proposes that a species
constitutes a population of organisms evolving independently from other such populations owing to a lack of gene
flow. By “independently,” it is meant that new mutations arising in one species cannot spread readily into another
species (Barraclough et al. 2003; de Queiroz 2007). Integrative studies on the nature and origins of species are us-
ing an increasingly wider range of empirical data to delimit species boundaries (Coyne & Orr 1998; Fontaneto et al.
2007; Knowles & Carstens 2007; Leaché et al. 2009), rather than relying solely on morphology and traditional taxo-
nomic methods. Under the GLC implemented herein, molecular phylogenies were used to recover monophyletic
mitochondrial lineages (populations) of individuals in order to develop initial species-level hypotheses—the group-
ing stage of Hillis (2019). Discrete color pattern data and univariate and multivariate analyses of morphological data
were then used to search for characters and morphospatial patterns bearing statistically significant differences that
were consistent with the species-level hypotheses—the construction of boundaries representing the hypothesis-test-
ing step of Hillis (2019)—thus providing an independent framework to complement the molecular based analyses.
Molecular data and analyses. Genomic DNA was isolated from liver or skeletal muscle specimens stored in
95% ethanol using a SPRI magnetic bead extraction protocol (https://github.com/phyletica/lab-protocols/blob/mas-
ter/extraction-spri.md). The 12S and 16S rRNA genes were amplified using a double-stranded Polymerase Chain
Reaction (PCR) under the following conditions: 1.0 µl genomic DNA (10–30 µg), 1.0 µl light strand primer (con-
centration 10 µM), 1.0 µl heavy strand primer (concentration 10 µM), 1.0 µl dinucleotide pairs (1.5 µM), 2.0 µl 5x
buffer (1.5 µM), MgCl 10x buffer (1.5 µM), 0.1 µl Taq polymerase (5u/µl), and 6.4 µl ultra-pure H2O. PCR reac-
tions were executed on a Bio-Rad gradient thermocycler under the following conditions: initial denaturation at 95°C
for 2 min, followed by a second denaturation at 95°C for 35 s, annealing at 54–56°C for 35 s, followed by a cycle
extension at 72°C for 35 s, for 31 cycles. All PCR products were visualized on a 1.0 % agarose gel electrophoresis.
Successful PCR products were sent to GENEWIZ® for PCR purification, cycle sequencing, sequencing purifica-
tion, and sequencing using the same primers as in the amplification step (Table 1). Sequences were analyzed from
both the 3’ and the 5’ ends separately to confirm congruence between reads. Forward and reverse sequences were
uploaded and edited in GeneiousTM v11 (Kearse et al. 2012). Following sequence editing we aligned the regions us-
ing the MAFTT v7.017 (Katoh & Kuma 2002) plugin under the default settings in GeneiousTM (Kearse et al. 2012).
All new sequences were uploaded to GenBank (Table 2).
Ingroup sequences included eight samples of Sphenomorphus stellatus from across its range in Indochi-
na including a topotype from Bukit Larut, Perak, and 13 samples of S. preasignis across its range in Peninsular

TAXONOMY OF SPHENOMORPHUS STELLATUS AND S. PREASIGNIS Zootaxa 4683 (3) © 2019 Magnolia Press · 383
FIGURE 1. Known distribution and localities for Sphenomorphus annamiticus, S. praesignis, S. preylangensis sp. nov., and
S. stellatus. Stars represent type localities. Peninsular Malaysia: 1 = Bukit Larut, Perak; 2 = Cameron Highlands, Pahang; 3
= Fraser’s Hill, Pahang; 4 = Genting Highlands, Pahang; 5 = Gunung Tahan, Pahang; 6 = Gunung Lawit, Terengganu; 7 = Gu-
nung Tebu, Terengganu. Thailand: 8 = Khao Wang Hip, Nakon Si Thammarat Province; 9 = Khao Soi Dao Wildlife Sanctuary,
Chantaburi Province; 24 = Phu Wiang, Khon Kean Province. Cambodia: 10 = Chum Noab, Koh Kong Province; 11 = Bokor
National Park, Kampot Province; 21 = Phnom Chi, Prey Lang Wildlife Sanctuary, Kampong Thom Province. Vietnam: 12 =
Ma Da, Dong Nai Province; 13 = Cat Tien, Dong Nai Province; 14 = Dalat, Annam, Lam Dong Province; 15 = Thac Nham,
Kon Tum Province; 16 = Buon Luoi Village, Gia Lai Province; 17 = Tram Lap Village, Gia Lai Province; 18–20 = Mang Canh
Village and vicinity, Kon Tum Province; 22 = Phuc-Son, Annam (now Phuoc Son District, Quang Nam Province); 23 = K Bang,
Gia Lai Province; and 24 = Phu Wiang, Khon Kean Province from Cox et al. (1998).

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384 · Zootaxa 4683 (3) © 2019 Magnolia Press
Malaysia. Honda et al. (2006) demonstrated with 12S and 16S rRNA sequence data that S. praesignis was nested
within Tropidophorus and was the sister species to an Indochinese clade composed of nine species. Using a larger
data set composed of 12 species and four mitochondrial and five nuclear markers, Linkem (2013) demonstrated that
S. stellatus and S. praesignis were sister species and together composed the sister lineage to the Indochinese Tropi-
dophorus. We used seven species of the Indochinese Tropidophorus as an outgroup to root the tree.
TABLE 1. Primers used for PCR amplification and sequencing of 12S and 16S rRNA genes.
Primer name Primer sequence Citation
L1091 5’-AAACTGGGATTAGATACCCCACTAT-3’ (Kocher et al. 1989)
H1478 5’-GAGGGTGACGGGCGGTGTGT-3’ (Kocher et al. 1989)
L2606 5’-CTGACCGTGCAAAGGTAGCGTAATCACT-3’ (Hedges et al. 1993)
H3056 5’-CTCCGGTCTGAACTCAGATCACGTAGG-3’ (Hedges et al. 1993)
TABLE 2. GenBank accession numbers for the newly recorded specimens used for the molecular phylogenetic analyses.
— indicates missing locus.
Taxon Catalog no. Map locality = Locality data GenBank nos. 12, 16s
Sphenomorphus
annamiticus
ZMMU R 13810 13 = Cat Tien, Dong Nai Province, Vietnam MN414380, MN414416
S. annamiticus ZMMU R 14016 12 = Ma Da, Dong Nai Province, Vietnam MN414381, MN414417
S. annamiticus ZMMU R 14618 15 = Thac Nham, Kon Tum Province, Vietnam MN414382, MN414418
S. annamiticus FMNH 267739 10 = Chum Noab, Koh Kong Province, Cam-
bodia
MN414383, MN414419
S. annamiticus CBC 2530 11 = Bokor National Park, Kampot Province,
Cambodia
MN414384, —
S. annamiticus ZISP 30194 20 = Mang Canh Village, Kon Tum Province,
Vietnam
MN414385, MN414420
S. annamiticus IEBR 39484 23 = K Bang, Gia Lai Province, Vietnam —, HM773221
S. praesignis LSUHC 11231 7 = Gunung Tebu, Terengganu, Peninsular
Malaysia
—, MN414421
S. praesignis LSUHC 8059 3 = Fraser’s Hill, Pahang, Peninsular Malaysia —, MN414422
S. praesignis LSUHC 9933 3 = Fraser’s Hill, Pahang, Peninsular Malaysia —, MN414423
S. praesignis LSUHC 6480 3 = Fraser’s Hill, Pahang, Peninsular Malaysia —, MN414424
S. praesignis LSUHC 6483 3 = Fraser’s Hill, Pahang, Peninsular Malaysia MN414386, MN414425
S. praesignis LSUHC 8058 3 = Fraser’s Hill, Pahang, Peninsular Malaysia MN414387, MN414426
S. praesignis LSUHC 9095 3 = Fraser’s Hill, Pahang, Peninsular Malaysia —, MN414427
S. praesignis LSUHC 8085 3 = Fraser’s Hill, Pahang, Peninsular Malaysia —, MN414428
S. praesignis LSUHC 9852 1 = Bukit Larut, Perak, Peninsular Malaysia —, MN414429
S. praesignis LSUHC 9853 1 = Bukit Larut, Perak, Peninsular Malaysia —, MN414430
S. praesignis LSUHC 9040 1 = Bukit Larut, Perak, Peninsular Malaysia —, MN414431
S. praesignis LSUHC 10593 1 = Bukit Larut, Perak, Peninsular Malaysia —, MN414432
S. preylangensis
sp. nov.
CBC 2348 21 = Phnom Chi, Prey Lang, Kampong Thom,
Cambodia
MN414388, —
S. preylangensis
sp. nov.
CBC 2403 21 = Phnom Chi, Prey Lang, Kampong Thom,
Cambodia
MN414389, MN414433
S. preylangensis
sp. nov.
CBC 2405 21 = Phnom Chi, Prey Lang, Kampong Thom,
Cambodia
MN414390, MN414434
S. stellatus LSUHC 13483 1 = Bukit Larut, Perak, Peninsular Malaysia MN414391, MN414435
Tropidophorus
berdmorei
CAS 204900 Sagaing, Myanmar MN414392, MN414436
T. berdmorei CAS 204901 Sagaing, Myanmar MN414393, MN414437
T. berdmorei CAS 204902 Sagaing, Myanmar MN414394, MN414438
......continued on the next page

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TABLE 2. (Continued)
Taxon Catalog no. Map locality = Locality data GenBank no.
T. berdmorei CAS 210182 Sagaing, Myanmar —, MN414439
T. berdmorei CAS 206629 Bago, Myanmar MN414395, MN414440
T. berdmorei CAS 208417 Bago, Myanmar MN414396, MN414441
T. berdmorei CAS 208474 Bago, Myanmar MN414397, MN414445
T. berdmorei CAS 222108 Bago, Myanmar MN414398, MN414442
T. berdmorei CAS 228558 Tanintharyi, Myanmar MN414399, MN414443
T. hainanus ROM 30497 Hainan Island, China AB222944, AB222960
T. murphyi ROM 41223 Quang Thanh Village, Cao Bang, Vietnam AB222945, —
T. murphyi ROM 41224 Quang Thanh Village, Cao Bang, Vietnam —, AB222961
T. robinsoni MNHN 1999-7694 Phang-Nga, Thailand AB222939, AB222955
Tropidophorus sp. 1 CAS 243847 Tanintharyi, Myanmar MN414401, MN414446
Tropidophorus sp. 1 CAS 243950 Tanintharyi, Myanmar MN414402, MN414447
Tropidophorus sp. 1 CAS 246790 Tanintharyi, Myanmar MN414403, MN414448
Tropidophorus sp. 1 CAS 246791 Tanintharyi, Myanmar MN414404, MN414449
Tropidophorus sp. 1 CAS 246792 Tanintharyi, Myanmar MN414405, —
Tropidophorus sp. 1 CAS 247240 Tanintharyi, Myanmar MN414406, MN414450
Tropidophorus sp. 1 CAS 274451 Tanintharyi, Myanmar MN414407, MN414451
Tropidophorus sp. 1 CAS 247793 Tanintharyi, Myanmar MN414408, —
Tropidophorus sp. 1 CAS 247848 Tanintharyi, Myanmar MN414409, —
Tropidophorus sp. 1 CAS 247849 Tanintharyi, Myanmar MN414410, —
Tropidophorus sp. 2 CAS 244969 Kachin, Myanmar MN414411, MN414452
Tropidophorus sp. 2 LSUHC 14563 Kachin, Myanmar MN414413, MN414453
Tropidophorus sp. 2 LSUHC 14655 Kachin, Myanmar MN414414, MN414454
T. thai KUZR 27510 AB222940, AB222956
Two model-based phylogenetic analyses were employed. A Maximum Likelihood (ML) analysis was imple-
mented in IQ-TREE (Nguyen et al. 2015). One-thousand bootstrap pseudoreplicates via the ultrafast bootstrap
(UFB) approximation algorithm (Hoang et al. 2018; Minh et al. 2013) were employed and nodes having UFB val-
ues of 95 and above were considered highly supported (Minh et al. 2013). A Bayesian inference (BI) phylogenetic
analysis was implemented in MrBayes 3.2.3. on XSEDE (Ronquist et al. 2012) using the CIPRES Science Gateway
(Cyberinfrastructure for Phylogenetic Research; Miller et al. 2010) employing default priors and an HKY+Gamma
model of evolution for the tRNA and the second codon position and GTR+G to the first and third codon positions.
Two independent Markov Chain Monte Carlo (MCMC) analyses were performed with four chains, three hot and
one cold. The simulation ran for 100 million generations, was sampled every 10 thousand generations using the
MCMC, and the first 25% of each run was discarded as burn-in. Convergence and stationarity of all parameters from
both runs were checked in Tracer v1.6 (Rambaut et al. 2014) to ensure effective sample sizes (ESS) were above
200. Converged trees from both runs were combined using the sumt command and a 50% majority-rule consensus
tree was constructed. Nodes with Bayesian posterior probabilities (BI) of 0.95 and above were considered well-sup-
ported (Hulsenbeck et al. 2001; Wilcox et al. 2002). After removing outgroup taxa, MEGA7 (Kumar et al. 2016)
was used to calculate uncorrected pairwise sequence divergence among the ingroup species.
Morphological data and analyses. All measurements were made with MitutoyoTM digital calipers to the near-
est 0.1 mm. Scale counts were made on the right side of the body when possible under a Nikon SMZ 1500 dissect-
ing microscope. Scale terminology (Fig. 2) is modified from Taylor (1935), Nguyen et al. 2011, and Grismer et al.
(2018a). Measurements taken were snout–vent length (SVL) measured from the tip of the rostral scale to the vent;
tail length (TAL) measured from the vent to the tip of the tail; head length (HL) measured from the posterior margin
of the retroarticular process to the tip of the snout; head width (HW) measured at the widest point of the head pos-
terior to the eyes; head height (HH) measured across the highest part of the head posterior to the eyes; snout length
(SNL) measured from the anterior border of the orbit (not the eyeball) to the tip of the snout; forelimb to snout (SFL)
measured from the anterior margin of the forelimb insertion on the body to the tip of the snout; distance from tip

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386 · Zootaxa 4683 (3) © 2019 Magnolia Press
of snout to anterior border of ear opening (STL); eyeball diameter (ED) measured from the posterior to the anterior
margins of the visible portion of the eyeball; eye to tympanum (ET) measured from the anterior margin of the ear
opening to the posterior margin of the orbit; tympanum diameter (TD) measured as the vertical length across the ear
opening; axilla-groin length (AG) measured from the anterior margin of the hind limb at its insertion point of the
body to the posterior margin of the forelimb at its insertion point on the body with the upper limb sections held at
right angles to the body; forelimb length (FIL) measured from the insertion point of the forelimb on the body to the
base of the fourth finger with the brachium held at a right angle to the body; and hind limb length (HIL) measured
from the insertion point of the hind limb on the body to the base of the fourth toe with the thigh held at a right angle
to the body.
Scale counts taken were the number of supraoculars contacted by the frontoparietal, midbody scale rows (MB)
counted as the number of longitudinal scale rows encircling the body at a point midway between the limb insertions,
paravertebral scale rows (PV) counted as the number of scales in a line from, but not including, the nuchal scales to
a point on the dorsum opposite the vent, ventral scale rows (VS) counted as a row of scales between the postmental
and the precloacal scales, nuchal scales (NU) counted as the number of the scales between opposing upper second-
ary temporals (ST) on each side of the head that contact the parietals, post-parietal scales (PPS) counted as the num-
ber of scales contacting the parietals (NU plus upper ST), number of primary, secondary, and tertiary temporals (PT,
ST, and TT, respectively), superciliaries (SC), supraoculars (So), loreals (AL & PL), preoculars (Pr), postsuboculars
(#), supralabials (SL), infralabials (IL), fourth toe and finger subdigital lamellae (TL4 and FL4, respectively), num-
ber of caudal scales around the tail at the position of the tenth subcaudal scales, and size (enlarged or not relative
to adjacent scales) of subcaudal scales. Color pattern characters included the presence or absence of dark vertebral
and lateral stripes, blotching on the head, labial patterning, the presence or absence of large, dark anterolateral spots,
presence or absence of dark labial sutures, and dark dorsal and subcaudal banding (bars). Museum acronyms follow
Sabaj (2016) except for LSUHC, La Sierra University Herpetological Collection, Riverside, California, USA and
LSUDPC La Sierra University Digital Photo Collection, Riverside, California, USA.
All statistical analyses were performed using the platform R v 3.2.1 (R Core Team 2015). Twelve of the 23
preserved specimens of Sphenomorphus setalltus sensu lato used in this study were not represented in the molecular
phylogenetic analyses. An a priori decision as to their placement in one of the four mitochondrial lineages prior to
additional downstream statistical analyses, was based on distribution and the presence or absence of dark vertebral
and lateral stripping. CUMZ 35440 from Khao Sebab (=Khao Soi Dao), Thailand was so faded that striping was not
discernable and its lineage placement was based only on distribution. Following this, all individuals were subjected
to a discriminant function analysis (DFA) using the MASS Package in R (Ripley et al. 2018) based on nine meristic
characters (PPS, SC, SL, IL, MB, PV, VS, TL4, FL4) to assess the probability of the placement of each individual
into a particular mitochondrial lineage. DFA uses linear combinations of untransformed data to characterize and
separate predefined groups and explicitly attempts to model the difference between them. The predict() command
was used to calculate the posterior probability for the lineage membership of each individual. In all but one case, a
priori (see below) membership assignment was correct.
A multivariate analysis of variance (MANOVA) using Wilks’ lambda (owing to unequal sample sizes) was
conducted to ascertain if the population/lineage pairs delimited in the molecular phylogenies were significantly dif-
ferent (p < 0.05) in multivariate morphological space. Morphospatial positions were subsequently visualized using
principal component analysis (PCA) from the ADEGENET package in R (Jombart et al. 2010) to determine if their
positioning was consistent with the putative species boundaries delimited by the molecular phylogenetic analy-
ses and coroborated by statistical differences reveled in the ANOVA and TukeyHSD analyses (see below). PCA,
implemented by the prcomp() command in R, is an indiscriminate analysis plotting the overall variation among
individuals (i.e. data points) while treating each individual independently (i.e. not coercing data points into pre-de-
fined groups). Meristic data used were PPS, SC, SL, IL, MB, PV, VS, TL4 and FL4. The number of caudal scales
at the position of tenth subcaudal scale was not used as these data were missing for some specimens. Because the
data were highly skewed by values ranging from 5–77, all characters were scaled to their standard deviation prior to
analysis in order to standardize their distribution so as to ensure characters with very large and very low values did
not over-leverage the results owing to intervariable nonlinearity and to ensure the data were analyzed on the basis
of correlation not covariance.

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FIGURE 2. Head scale nomenclature and their positional relationship and size illustrated by the adult female Sphenomorphus
stellatus LSUHC 13843 (SVL = 88.0 mm) from the type locality of Bukit Larut, Perak, Malaysia. A) dorsal view and B) right
lateral view. Terminology is modified from Taylor (1935). AL = anterior loreal, Cs = chinshield; F = frontal, Fn = frontonasal,
Fp = frontoparietal, IL = infralabial, Ip = interparietal, M = mental, N = nasal, Nu = nuchal, P = parietal, Pf = prefrontal, PL =
posterior loreal, Pm = postmental, Pr = preocular, Prs = presubocular, PT = primary temporal, Psl = postsupralabial, Pso = post-
supraocular (maybe homologous to the last superciliary of Taylor (1935), Pto = postocular, R = rostral, SL = supralabial, So =
supraocular, ST = secondary temporal, and TT = tertiary temporal. * = superciliary and # = postsubocular. Illustration by LLG.

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388 · Zootaxa 4683 (3) © 2019 Magnolia Press
Independent of the MANOVA, analyses of variance (ANOVA) were conducted to determine which, if any,
character means differed statistically (p ≤ 0.05) between any combinations of population/lineage pairs. Characters
bearing statistical mean differences were subjected to a Tukey HSD test to ascertain which populations differed
significantly from each other. The differences were visualized using boxplot analyses.
Results
Both the ML and BI phylogenetic analyses recovered trees with identical topologies bearing four relatively deeply
divergent mitochondrial lineages with all nodes strongly supported (BI 1.00/UFB 100; Fig. 3). Sphenomorphus
stellatus from Peninsular Malaysia was recovered as the sister species of S. praesignis and not S. stellatus from
Indochina. Additionally, the analyses recovered a relatively deep uncorrected pairwise sequence divergence of 6.9
% between two reciprocally monophyletic Indochinese lineages (Fig. 3).
FIGURE 3. Maximum likelihood consensus tree. Black circles represent nodes supported by BI and UFB support values of 1.00
and 100, respectively. Numbers in parentheses correspond to the localities in Figure 1.
The DFA correctly placed all specimens of Sphenomorphus annamiticus (see below for the resurrection of this
nomen), S. preylangensis sp. nov. (see below for its description), and S. praesignis in the appropriate mitochon-

TAXONOMY OF SPHENOMORPHUS STELLATUS AND S. PREASIGNIS Zootaxa 4683 (3) © 2019 Magnolia Press · 389
drial clade. CUMZ 33450 from Khao Soi Dao whose color pattern was too faded to be evaluated, was placed in
S. annamiticus by the DFA with a 99.9% probability. Furthermore, we have examined a photograph of a specimen
(LSUDPC 10975) from the same locality that has the diagnostic dark vertebral and lateral stripes (Fig. 4A). One
specimen (BMNH 1921.4.1.158) from Dalat, Annam, Vietnam was placed in S. stellatus sensu stricto (see below
for the geographic restriction of this nomen) with a 79.1% probability and within S. annamiticus with a 21.0% prob-
ability. BMNH 1921.4.1.158 bears the dark vertebral and lateral stripes of all other specimens of S. annamiticus in-
cluding those in the phylogeny and its distribution is geographically intermediate between the northern and southern
Vietnamese populations of S. annamiticus (Figs 1). Therefore, based on color pattern and geography we consider
BMNH 1921.4.1.158 to be S. annamiticus.
FIGURE 4. Sphenomorphus annamiticus. A. LSUDPC 10975 from Khao Soi Dao Wildlife Sanctuary, Chantaburi Province,
Thailand. Photograph by Ian Dugdale. B. CBC 02530 from Bokor National Park, Kampot Province, Cambodia. Photograph by
Hun Seiha. C. LSUDPC 4853 from Kon Tum, Kon Tum Province, Vietnam. Photograph by Nikolai Orlov. D. ZISP 19804 from
Buon Luoi Village, An Khe District, Gia Lai Province, Vietnam. Photograph by Nikolai Orlov.
The MANOVA indicated that highly significant morphospacial differences existed within the data set (MANO-
VA Wilks’ lambda, p=2.2-16) as visualized in the PCA (Fig. 5). The ANOVA and subsequent Tukey HSD tests indi-
cated that all four mitochondrial lineages bear statistically significant mean differences among them across various
combinations of characters (Table 3; Fig. 6). The PCA analysis is consistent with the phylogenetic analyses and the
ANOVA/Tukey HSD analyses by recovering all four mitochondrial lineages as occupying non-overlapping mor-
phospatial regions for nearly all combinations of species along the collective ordination of the first two principal
components (Fig. 5). Principal component 1 (PC1) accounted for 27.6 % of the variation in the data set and loaded
most heavily for ventral scales (Table 4). PC2 accounted for 21.2% of the variation and loaded most heavily for
fourth finger and toe lamellae and PC3 counted for an additional 16.1% of the variation and loaded most heavily for
infralabial scales. An ANOVA and subsequent Tukey HSD tests of the combined factor loadings for PC1, PC2, and
PC3 which account for 64.9% of the variation in the data set (Table 4) and are collectively the three most informa-
tive PCs for the location of the lineage centroids, indicate that all species occupy a statistically different location
from one another in morphospace (Table 5). The DAPC showed wide separation among all species with the excep-
tion of slight overlap of the 95% confidence ellipses of S. stellatus sensu stricto and S. annamiticus.

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TABLE 3. Significant Tukey HSD p values between species pairs bearing statistically different mean values for six mer-
istic characters.
Character Species pair p value
Fourth finger lamellae stellatus-annamiticus 0.0001
Fourth finger lamellae stellatus-praesignis 5.52E-05
Fourth finger lamellae stellatus-preylangensis sp. nov 2.15E-05
Fourth toe lamellae stellatus-annamiticus 0.02809
Fourth toe lamellae stellatus-praesignis 0.0014
Fourth toe lamellae stellatus-preylangensis sp. nov 0.0021
Infralabials preylangensis sp. nov.-praesignis 0.0096
Midbody scales praesignis-annamiticus 1.56E-13
Midbody scales preylangensis sp. nov.-praesiginis 9.47E-09
Midbody scales stellatus-praesignis 3.19E-06
Paravertebral scales praesignis-annamiticus 2.19E-06
Paravertebral scales preylangensis sp. nov.-annamiticus 3.72E-05
Paravertebral scales stellatus-annamiticus 0.0053
Ventral scales praesignis-annamiticus 2.94E-06
TABLE 4. Summary statistics and principal component analysis scores for Sphenomorphus preylangensis sp. nov., S.
annamiticus, S. praesignis, and S. stellatus. Abbreviations are listed in the Materials and methods.
PC1 PC2 PC3 PC4 PC5
Standard Deviation 1.575533895 1.382509842 1.203923207 0.982769596 0.759571282
Proportion of Variance 0.27581 0.21237 0.16105 0.10732 0.06411
Cumulative Proportion 0.27581 0.48818 0.64923 0.75655 0.82065
Eigenvalue 2.482307055 1.911333463 1.449431088 0.965836079 0.576948532
PPS -0.322061724 -0.259762979 0.38859758 0.237307125 -0.634443577
SC 0.321310667 -0.331470466 -0.425853075 0.139241222 -0.342683416
SL 0.084061626 0.183876385 0.515535523 0.640289877 0.235450581
IL 0.127649562 -0.010199426 0.532966364 -0.645888855 -0.267172806
MB -0.509866468 -0.104703803 -0.217050943 -0.068003701 0.094220514
PV -0.482338352 -0.041733577 -0.081547477 0.188167174 -0.184742573
VS -0.514529227 0.210167464 0.013554165 -0.231325845 0.240292144
TL4 0.103985923 0.631861424 -0.021064327 -0.00283318 -0.153120635
FL4 -0.038825698 0.576725387 -0.251838309 0.060021739 -0.478578701
TABLE 4. (Continued)
PC6 PC7 PC8 PC9
Standard Deviation 0.724591992 0.674448929 0.589934506 0.53498238
Proportion of Variance 0.05834 0.05054 0.03867 0.0318
Cumulative Proportion 0.87899 0.92953 0.9682 1
Eigenvalue 0.525033556 0.454881358 0.348022722 0.286206147
PPS 0.418186457 -0.101436223 -0.17472664 -0.057091325
SC -0.211606082 0.457834895 -0.260305574 -0.382840679
SL -0.183115409 0.429556017 0.068768452 -0.07182907
IL -0.340405151 0.300917535 0.05665729 0.036845839
MB 0.100917146 0.603529207 -0.10444565 0.532089757
PV -0.775778296 -0.294042866 -0.00087994 0.033576506
VS 0.10587999 0.149061893 -0.115193874 -0.730036976
TL4 -0.034660369 -0.048172215 -0.732856726 0.15949772
FL4 0.080671466 0.172567219 0.576640428 -0.031877325

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FIGURE 5. A. Plot of the principal component analysis ordinated along the first two principal components. B. Plot of the dis-
criminant analysis of principal components.
TABLE 5. Significant Tukey HSD p values between all possible species pairs based of the means from the combined
factor loadings of PC1, PC2, and PC 3.
Species pair p value
praesignis-annamiticus 3.56E-05
preylangensis sp. nov.-annamiticus 8.50E-01
stellatus-annamiticus 1.00E-01
preylangensis sp. nov.-praesignis 2.36E-02
stellatus-praesignis 4.10E-03
stellatus-preylangensis sp. nov.9.18E-01
Taxonomy
The phylogenetic relationships render Sphenomorphus stellatus sensu lato paraphyletic with respect to S. preasignis
(Fig. 3). The data show that the four mitochondrial lineages of this clade 1) bear relatively deep genetic divergences,
2) are diagnosable in various combinations by discrete color pattern differences (Fig. 7) and meristic characters
with statistically different means (Tables 3, 5), and 3) occupy statistically different regions in morphospace (Fig. 5
and Table 3) which we interpret as evidence that these four lineages are on non-reticulating evolutionary trajecto-
ries. Therefore, to construct a taxonomy that is consistent with the evolutionary history of this clade, we describe
the unstriped specimens from Prey Lang (Phnom Chi) as a new species. Boettger (1901) described Lygosoma
(Hinulia) annamiticum from two specimens from “Phuc-Son in Annam” (now Phuoc Son District in Quang Nam
Province, southwest of Da Nang, Fig. 1). Boettger (1901) noted the type specimens had “drei breiten schwarzen
Fleckenbandern” [three broad black flecked bands] (stripes) that are still visible on the lectotype SMF 14445.
Lygosoma annamiticum was subsequently synonymized with S. stellatus by Smith (1935). In the present paper,
we follow Boettger’s (1901) original definition and resurrect this taxon as S. annamiticus (Boettger, 1901) for the
striped specimens from Thailand, Cambodia, and Vietnam (the adjectival species name is adjusted to the gender of
“Sphenomorphus” which is masculine). The nomen S. stellatus is herein restricted to populations from Peninsular
Malaysia while taxonomy of S. preasignis remains unchanged.

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FIGURE 6. Boxplots of characters bearing significantly different mean values between the species pairs listed above each plot
as determined by Tukey HSD tests. Boxes represent the 50% quartiles, the horizontal black bars the medians, and the blue circles
the means. Abbreviations are in the Materials and Methods.
Sphenomorphus preylangensis sp. nov.
Suggested Common Name: Prey Lang Forest Skink
(Figs. 7–9, 11)
Holotype. Adult female CBC 02348 from Phnom Chi, Prey Lang Wildlife Sanctuary, Preah Vihear Province, Cam-
bodia (11°34.187’ N 104°53.274’ E, at 320 m in elevation) was collected by Neang Thy & Hun Seiha on 23 June
2014.

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TABLE 6. Summary statistics and diagnostic characters among Sphenomorphus preylangensis sp. nov., S. annamiticus,
S. stellatus, and S. praesignis. SD = standard deviation and n = sample size.
S. preylangensis sp. nov. S. annamiticum S. stellatus S. praesignis
postparietal scales (PPS)
mean (±SD) 6.0 (±0.00) 5.4 (±0.67) 5.4 (±0.54) 5.8 (±0.38)
range 6 5–7 5 or 6 5 or 6
n 6 12 5 18
superciliary scales (SC)
mean (±SD) 8.8 (±0.20) 8.6 (±0.45) 8.4 (±0.55) 8.4 (±0.85)
range 8 or 9 8 or 9 8 or 9 6–9
n 6 12 5 18
supralabial scales (SL)
mean (±SD) 7.2 (±0.26) 7.0 (±0.00) 7.0 (±0.00) 6.9 (±0.32)
range 7 or 8 7 7 6 or 7
n 6 12 5 18
infralabials (IL)
mean (±SD) 7.0 (±0.00) 6.4 (0.51) 6.4 (0.58) 6.3 (0.46)
range 7 6 or 7 6 or 7 6 or 7
n 6 12 5 18
midbody scale rows (MB)
mean (±SD) 24.0 (±0.00) 23.3 (±1.56) 24.8 (±1.30) 28.3 (±0.97)
range 24 21–26 23–26 27–30
n 6 12 5 18
paravertebral scales (PV)
mean (±SD) 64.8 (±2.32) 58.2 (±3.04) 63.0 (±0.71) 64.0 (±2.52)
range 61–68 53–62 62–64 59–69
n 6 12 5 18
ventral scales (VS)
mean (±SD) 66.5 (±2.95) 61.5 (±3.15) 65.8 (±1.64) 69.6 (±4.29)
range 63–71 55–65 64–68 59–69
n 6 12 5 18
fourth toe lamellae (TL4)
mean (±SD) 17.7 (±0.82) 19.4 (±1.52) 22.8 (±2.39) 18.4 (±2.68)
range 17–19 17–22 20–26 14–23
n 6 12 5 18
fourth finger lamellae (FL4)
mean (±SD) 12.3 (±1.03) 13.1 (±1.44) 16.0 (±01.58) 13.1 (±0.68)
range 11–14 11–16 14–18 12–15
n 6 12 5 18
Dark vertebral and lateral stripes absent present absent absent
Dark markings on top of head large blotches large blotches small speckles large blotches
Dark transverse subcaudal bars present present absent present
Thin dark dorsal caudal bands present present absent present
Labial margins edged in black present present absent present
Large dark anterolateral spots absent absent absent present
Paratypes. CBC 02349 (female) and CBC 02403-06 (juveniles) bear the same collection data as the holotype.
Diagnosis. Sphenomorphus preylangensis sp. nov. can be separated from all other species of Sphenomorphus
by having the unique combination of a maximum adult female SVL of 87.6 mm; head, body, and supracaudal
scales smooth; frontal scale not divided; prefrontals not in contact; parietals in contact posterior to interparietal;

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parietals not divided; six scales bordering the parietals; four nuchals; four supraoculars; two loreals; anterior loreal
not divided; loreals in contact with supralabials; no deep postnasal groove; eight or nine superciliaries; superciliary
row not interrupted by fourth supraocular; lower eyelid scales large; seven or eight supralabials; seven infralabials;
three pairs of chinshields; one primary temporal scale; two secondary temporals; upper secondary temporal large;
no subtemporals; 24 midbody scale rows; 61–68 paravertebrals; paravertebrals slightly wider than other dorsals;
63–71 ventrals; two enlarged precloacals; 11–13 scales around tail at level of tenth subcaudal; anterior subcaudals
divided; unpaired subcaudals enlarged; 17–19 subdigital lamellae beneath fourth toe; 11–14 subdigital lamellae
beneath fourth finger; no wide, dark, vertebral or lateral stripes or blotches; dark blotches on top of head; no dark
anterolateral spots on the flanks; dark transverse subcaudal bars on original tail; thin, dark, dorsal caudal bands; and
labial margins edged with black. The nine diagnostic meristic and the six color pattern characters are scored across
all clade members in Table 6.
FIGURE 7. A. Sphenomorphus stellatus (LSUHC 13483) from the Bukit Larut, Perak, Peninsular Malaysia. Photograph by L.
L. Grismer. B. Sphenomorphus annamiticus (ZISP 30194) from Mang Canh Village, Kon Tum Province, Vietnam. Photograph
by Nikolai Orlov. C. Sphenomorphus preylangensis sp. nov. (CBC 02404) from Phnom Chi, Prey Lang Wildlife Sanctuary,
Cambodia. Photograph by Neang Thy. D. Sphenomorphus praesignis (LSUDPC 9558) from Fraser’s Hill, Pahang, Peninsular
Malaysia. Photograph by L. L. Grismer.
Description of holotype. Adult female, SVL 79.9 mm; TAL 53.3 mm, partially regenerated; head moderate,
snout slightly pointed, rounded in dorsal and lateral profile, subtriangular, distinct from neck; head scales large,
smooth; HL 16.5 mm, longer than wide, HW 10.5 mm; head somewhat depressed, HH 8.1 mm; rostral 2.5 mm wide,
0.9 mm long, in contact with first supralabials and nasals laterally, frontonasal dorsally; frontonasal wider than long,
single, in contact with nasal and first loreal laterally, prefrontals and frontal posteriorly; prefrontals separated, con-
tacting loreals and preoculars laterally and first superciliary posteriorly; frontal subtriangular, in lateral contact with
first superciliary and first, second, and third supraoculars, and frontoparietals posteriorly; four supraoculars, first
subtriangular, second subrectangular, third rectangular, fourth semicircular; frontoparietals divided medially, each
in lateral contact with third and fourth supraoculars, and parietals and interparietal posteriorly; interparietal subtri-
angular, eyespot present; large parietals in contact posterior to interparietal, contacting upper secondary temporal
laterally and nuchals posteriorly; six scales bordering posterolateral margins of parietals; four nuchals in contact
with parietals; 7R/L supralabials, seventh largest, fifth below center of eye; nostril in lower part of nasals; nasals
large, in contact with first and second supralabials ventrally, first loreal posteriorly; two undivided loreals similar
in size contacting supralabials; second loreal larger than first, horizontally subrectangular, in contact with second
and third supralabials ventrally, preoculars posteriorly, first superciliary and frontonasal dorsally; two preoculars,
lower slightly larger; eight superciliaries, not interrupted by fourth supraocular; two presuboculars; lower eyelid
bearing large scales; one postocular, in contact with first postsubocular anteriorly, primary temporal ventrally, post-

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supraocular dorsally, upper secondary temporal and parietal posteriorly; four postsuboculars, last three contacting
seventh supralabial; one postsupraocular; one primary temporal, two secondary temporals, lower one overlapping
the upper one; three tertiary temporals; one postsupralabial; seven infralabials, first smallest, first two contacting
postmental; mental large, semicircular; postmental large, single; three pairs of large chinshields in broad contact
with supralabials; second pair separated by a gular scale, third pair separated by three gulars; external ear opening
large, vertically elongate, vertical diameter 2.3 mm, horizontal diameter 1.2 mm, lacking anterior lobules; tympa-
num deeply recessed.
FIGURE 8. Dorsal, lateral, and ventral view of the holotype of Sphenomorphus preylangensis sp. nov. (CBC 02348) from
Phnom Chi, Prey Lang Wildlife Sanctuary, Cambodia. Photographs by Neang Thy.
Body scales smooth, cycloid, imbricate; dorsals larger than ventrals and flank scales; paravertebrals slightly
larger than adjacent dorsals; 24 longitudinal scale rows around midbody; 65 paravertebral scale rows intermittently

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interrupted by smaller scales; 69 ventrals; two enlarged, medial, precloacals; subcaudals similar in size to dorsal
caudals, larger than lateral caudals; limbs moderate in length, in contact when adpressed; palmar and plantar scales
rounded; single row of supradigitals; 14(R,L) smooth, subdigital lamellae beneath fourth finger; 19 (L,R) smooth,
subdigital lamellae beneath fourth toe.
Coloration in preservation (Fig. 8). Dorsum, head, flanks, limbs and tail bronze overlain with small, trans-
verse dark-brown markings countershaded posteriorly with light-brown markings giving the appearance of scat-
tered, short light-colored bars; darker scale edges in paravertebrals most distinct anteriorly; upper flanks bear a
darker bronze than the dorsum; irregularly shaped dark markings on head and neck. Scattered light-colored bars on
flanks and tail; ventral flanks and surfaces of body dull-yellow; dark edges on caudal scales form faint crossbands
encircling tail.
Variation (Fig. 9). All paratypes closely resemble the holotype in coloration and pattern. Paratype CBC 02405
is lighter and less boldly marked overall. Only the holotype CBC 02348 has the paravertebral scale series intermit-
tently interrupted by smaller scales. Caudal banding on juvenile paratypes (CBC02404-06) is more distinct and
pronounced. Paratype CBC 02403 has a regenerated tail and the tails of CBC 02405–06 are broken one-half to two-
thirds of the way down, respectively. That of CBC 02349 is missing. There seems to be no appreciative ontogenetic
change in color pattern although hatchlings have never been observed. Variation in meristics and mesurements is
presented in Table 7.
FIGURE 9. Type series of Sphenomorphus preylangensis sp. nov. from Phnom Chi, Prey Lang Wildlife Sanctuary, Cambodia.
Photograph by Neang Thy.

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TABLE 7. Meristic, mensural, and color pattern data from the type series of Sphenomorphus preylangensis sp. nov. Ab-
breviations are listed in the Materials and methods. R = right, L = left, / = data unobtainable or not applicable.
CBC CBC CBC CBC CBC CBC
2349 2406 2404 2348 2405 2403
Phnom Chi Phnom Chi Phnom Chi Phnom Chi Phnom Chi Phnom Chi
paratype paratype paratype holotype paratype paratype
Elevation (m) 320 320 320 192 320 320
Sex/maturity female juvenile juvenile female juvenile juvenile
Head scales large large large large large large
Head scales keeled no no no no no no
Frontonasal divided no no no no no no
Prefrontals in contact no no no no no no
Parietals contact posteriorly yes yes yes yes yes yes
Parietals divided no no no no no no
Interparietal eye spot yes yes yes yes yes yes
Scales bordering posterolateral
parietals
6 5 6 6 6 6
Nuchals 4 3 4 4 4 4
Supraoculars 4 4 4 4 4 4
Loreals 2 2 2 2 2 2
Anterior loreal divided no no no no no no
Loreals separated from supralabi-
als
no no no no no no
Postnasal groove deep absent absent absent absent absent absent
Superciliaries 8 8 8 8 8 9R/8L
Superciliary row interrupted by
4th supraocular
no no no no no no
Lower eyelid large scales large scales large scales large scales large scales large scales
Supralabials 7 6R/7L 7 7R/8L 7R/8L 7
2nd and 3rd supralabials keeled no no no no no no
Infralabials 7 7 7 7 7 7
1st infralabial elongate no no no no no no
Chinshields 3 3 3 3 3 3
1° temporals 1 1 1 1 1 1
2° temporals 2 2 2 2 2 2
Upper 2° temporal large yes yes yes yes yes yes
Subtemporals 0 0 0 0 0 0
Midbody scale rows 24 24 24 24 24 24
Paravertebrals 68 66 64 65 61 65
Paravertebral scales slightly
widened
yes yes yes yes yes yes
Dorsal body scales keeled or
smooth
smooth smooth smooth smooth smooth smooth
Ventral scales 66 63 65 69 65 71
Enlarged precloacals 2 2 2 2 2 2
R precloacal overlapped by L yes no yes no no yes
Medial cloacals enlarged / / / / / /
Supracaudals smooth or keeled smooth smooth smooth smooth smooth smooth
Scale rows at 10th subcaudal broken tail broken 11 13 11 11
Subcaudals slightly enlarged yes yes yes yes yes yes
......continued on the next page

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TABLE 7. (Continued)
CBC CBC CBC CBC CBC CBC
2349 2406 2404 2348 2405 2403
Phnom Chi Phnom Chi Phnom Chi Phnom Chi Phnom Chi Phnom Chi
paratype paratype paratype holotype paratype paratype
4th toe lamellae 18 17 18 19 17 17
4th finger lamellae 13 12 11 14 12 12
Coloration
Wide, dark, vertebral stripe or
blotches
no no no no no no
Wide, dark, dorsolateral stripe no no no no no no
Top of head blotched or speckled blotched blotched blotched blotched blotched blotched
Dark, transverse, subcaudal bars
or blotches
yes yes yes yes yes yes
Thin, dark, dorsal, caudal bands / yes yes / / /
Labial margins edged with black yes yes yes yes yes yes
Mensural (mm)
SVL 87.6 53.3 51.4 79.9 52.4 54.8
TAL broken broken 55.6 53.3 broken regenerated
AG 48.7 28.2 26.3 44.0 27.4 29.2
SNL 5.9 4.5 4.1 6.0 4.5 4.8
SFL 30.9 19.9 19.6 26.6 20.6 20.6
HL 17.2 12.2 11.6 16.5 11.2 12.6
HW 11 7.8 7.6 10.5 7.6 8
HH 7.5 5.3 5.1 8.1 5.5 5.5
STL 14.6 10.4 10.1 13.8 10.7 10.9
ED 4 2.8 2.7 3.6 2.6 2.9
ET 5.6 3.6 3.5 5.9 3.9 4.2
TD 2.3 1.8 1.9 2.3 1.6 1.7
FIL 23.1 14.9 14.3 21.4 14.6 14.9
HIL 28.4 19.3 19.3 27.8 19.0 20.3
Distribution (Fig. 1). Sphenomorphs preylangensis sp. nov. is known only from Phnom Chi in the Prey Lang
Wildlife Sanctuary, Kampong Thom Province, Cambodia (Fig. 1, locality 21). Cox et al. (1998) state that S. stel-
latus occurs in northeastern Thailand although no voucher specimens exist. They did present a photograph of a Thai
specimen (p. 117) taken by the late Jarujin Nabhitabhata but with no locality data. Chan-ard et al. (2015:127) state
that S. stellatus occurs at “Phu Wiang, Khon Kean Province in northeastern Thailand” (Fig. 1, locality 24) and at
“Khao Sa Bab (=Khao Soi Da), Chantaburi Province, in southeastern Thailand” (Fig. 1, locality 9). We suspect Phu
Wiang is likely the northeastern locality to which Cox et al. (1998) and Chan-ard et al. (2015) are referring to being
that Jarujin Nabhitabhata took the photograph and was an author on both books. Furthermore, skinks from Khao Sa
Bab (=Khao Soi Da) are S. annamiticus. Chan-ard et al. (2015) also stated that S. stellatus is found in “dead bark of
standing trees” which is from Taylor (1963:1009 “underneath dead bark on a standing tree”) referring to the Khao
Soi Da specimen and “in leaf litter” (p. 234) which likely refers to the Phu Wiang specimen. The photograph in Cox
et al. (1998) however, is not S. stellatus as the body stature is less robust and the color pattern is far too bold and
its lack of black vertebral and lateral stripes also precludes it from being S. annamiticus. However, the specimen is
indistinguishable in appearance from S. preylangensis sp. nov. (approximately 470 km to the southeast) and based
on the above inferences, we suspect this is another population of S. preylangensis sp. nov. or more likely a new,
closely related species. At this point we refer to this population as Sphenomorphus sp.
Etymology. The specific epithet preylangensis is a Latinized toponymic adjective named after the Prey Lang
Wildlife Sanctuary.

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TABLE 8. Meristic, mensural, and color pattern data from Sphenomorphus annamiticus. Abbreviations are listed in the Materials and methods. R = right, L = left, / = data unob-
tainable or not applicable.
Location in Fig. 1 10 11 9 14 13 12 15 16 17 19 18 20
FMNH CBC EHT BMNH ZMMU ZMMU ZMMU ZISP ZISP ZISP ZISP ZISP
267739 2530 35440 1921.4.1.158 R-13810 R-14016 R-14618 19804 30191 30192 30193 30194
Chum
Noab
Bokor Khao Soi
Dao
Lam Dong,
Dalat
Dong Nai,
Cat Tien
Dong Nai,
Ma Da
Kon Tum,
Thac Nham
Gia Lai,
Buon Luoi
Gia Lai,
Tram Lap
Kon Du
2005
Kon Tum,
Mang Canh
Kon Tum,
Mang Canh
Cambodia Cambodia Thailand Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam
Elevation (m) 200 126 ~1550 200 100 1200 1982 1985 2005 2006 2018
Sex/maturity m m juv m m f f m subadult
Head scales large large large large large large large large large large large large
Head scales keeled no no no no no no no no no no no no
Frontonasal divided no no no no no no no no no no no no
Prefrontals in contact no no yes no no no no yes yes yes yes yes
Parietals contact poste-
riorly
yes yes yes yes yes yes yes yes yes yes yes yes
Parietals divided no no no no no no no no no no no no
Interparietal eye spot yes yes yes yes yes yes yes yes yes yes yes yes
Scales bordering poste-
rolateral parietals
6 7 5 6 5 5 6 5 5 5 5 5
Nuchals 4 5 5 4 3 3 4 3 3 3 3 3
Supraoculars 4 4 4 4 4 4 5R/4L 4 4 4 4 4
Loreals 2 2 2 2 2 2 2 2 2 2 2 2
Anterior loreal divided no no no no no no no no no no no no
Loreals separated from
supralabials
no no no no no no no no no no no no
Postnasal groove deep yes absent present absent absent absent absent yes yes yes yes yes
Superciliaries 9 8 9 8 9 8 9 9 9 9 9 9
Superciliary row inter-
rupted by 4th supraocu-
lar
no no no no no no no no no no no no
Lower eyelid large
scales
large
scales
large
scales
large scales large scales large
scales
large scales large scales large scales large
scales
large scales large scales
Supralabials 7 7 7 7 7 7 7 7 7 7 7 7
......continued on the next page

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400 · Zootaxa 4683 (3) © 2019 Magnolia Press
TABLE 8. (Continued)
Location in Fig. 1 10 11 9 14 13 12 15 16 17 19 18 20
FMNH CBC EHT BMNH ZMMU ZMMU ZMMU ZISP ZISP ZISP ZISP ZISP
267739 2530 35440 1921.4.1.158 R-13810 R-14016 R-14618 19804 30191 30192 30193 30194
Chum
Noab
Bokor Khao Soi
Dao
Lam Dong,
Dalat
Dong Nai,
Cat Tien
Dong Nai,
Ma Da
Kon Tum,
Thac Nham
Gia Lai,
Buon Luoi
Gia Lai,
Tram Lap
Kon Du
2005
Kon Tum,
Mang Canh
Kon Tum,
Mang Canh
Cambodia Cambodia Thailand Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam
2nd and 3rd supralabials
keeled
no no no no no no no no no no no no
Infralabials 6 7 7 7 6 7 6 6 6 6 7 6
1st infralabial elongate no no no no no no no no no no no no
Chinshields 3 3 3 3 3 3 3 3 3 3 3 3
1° temporals 1 1 1 1 1 1 1 1 1 1 1 1
2° temporals 2 2 2 2 2 2 2 2 2 2 2 2
Upper 2° temporal large yes yes yes yes yes yes yes yes yes yes yes yes
Subtemporals 0 0 0 0 0 0 0 0 0 0 0 0
Midbody scale rows 21 23 22 24 23 23 24 22 26 24 26 22
Paravertebrals 59 57 54 58 53 55 57 62 60 62 61 60
Paravertebral scales
slightly widened
yes yes yes yes yes yes yes yes yes yes yes yes
Dorsal body scales
keeled or smooth
smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth
Ventral scales 61 59 62 65 62 65 65 62 63 62 55 57
Enlarged precloacals 2 2 2 2 2 2 2 2 2 2 2 2
R precloacal overlapped
by L
no yes no no no no no 5 6 6 6 5
Medial cloacals enlarged / / / / / / / / / / / /
Supracaudals smooth or
keeled
smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth smooth
Scale rows at 10th
subcaudal
16 13 12 13 13 13 13 11 13 12 13 11
Subcaudals slightly
enlarged
yes yes yes yes yes yes yes yes yes yes yes yes
4th toe lamellae 20 17 17 22 20 18 20 21 20 19 20 19
4th finger lamellae 12 11 12 16 14 13 14 15 13 13 12 12
......continued on the next page

TAXONOMY OF SPHENOMORPHUS STELLATUS AND S. PREASIGNIS Zootaxa 4683 (3) © 2019 Magnolia Press · 401
TABLE 8. (Continued)
Location in Fig. 1 10 11 9 14 13 12 15 16 17 19 18 20
FMNH CBC EHT BMNH ZMMU ZMMU ZMMU ZISP ZISP ZISP ZISP ZISP
267739 2530 35440 1921.4.1.158 R-13810 R-14016 R-14618 19804 30191 30192 30193 30194
Chum
Noab
Bokor Khao Soi
Dao
Lam Dong,
Dalat
Dong Nai,
Cat Tien
Dong Nai,
Ma Da
Kon Tum,
Thac Nham
Gia Lai,
Buon Luoi
Gia Lai,
Tram Lap
Kon Du
2005
Kon Tum,
Mang Canh
Kon Tum,
Mang Canh
Cambodia Cambodia Thailand Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam Vietnam
Coloration
Wide, dark, vertebral
stripe or blotches
yes yes / yes yes yes yes yes yes yes yes yes
Wide, dark, dorsolateral
stripe
yes yes / no no yes yes yes yes yes yes yes
Top of head blotched or
speckled
blotched blotched / blotched blotched blotched blotched blotched blotched blotched blotched blotched
Dark, transverse, sub-
caudal bars or blotches
yes yes yes no yes yes no / / / / /
Thin, dark, dorsal, cau-
dal bands
yes yes / yes yes yes yes / / / / /
Labial margins edged
with black
yes yes / yes yes yes yes yes yes yes yes yes
Mensural (mm)
SVL 51.1 67.7 57.9 66.8 53.0 49.4 66.9 77.1 75.9 71.6 62.8 41.5
TAL 53.1 72.3 58.2 49.6 26.5 53.5 68.6 / / / / /
AG 25.3 35.9 28.1 33.8 28.7 25.0 33.2 41.4 38.3 38.9 30.2 20.3
SNL 4.2 4.7 4.1 5.9 4.8 4.7 6.1 6.3 6.1 6.7 5.9 4.7
SFL 19 24.2 22.8 25.3 19.8 18.2 26.9 28.4 28.1 27.9 24.1 20.4
HL 10.9 13.4 9.9 14.5 10.3 9.6 13.4 18.8 18.9 18.2 16.6 12.2
HW 6.6 8.7 7.0 8.7 7.7 7.0 10.5 10.4 10.7 10 9.3 6.9
HH 4.7 7.1 5.9 67.0 6.1 5.3 8.0 8.5 8.4 8.4 6.9 4.3
STL 10 12.3 10.9 5.5 10.9 9.9 14.0 15.3 14.9 14.1 13.4 8
ED 2.7 3.4 2.5 3.8 2.9 2.7 3.3 4 4.2 3.9 3.3 2.8
ET 3.7 4.4 4.2 4.9 4.1 3.9 5.8 6.1 5.8 6 5.1 3.5
TD 1.3 1.8 0.91 1.8 1.7 1.3 2.0 1.6 1.8 1.8 1.6 1.2
FIL 15.7 18.1 16.2 20.2 16.8 15.4 22.3 27.3 26.9 26.2 22.7 14.7
HIL 21.1 23.6 21.8 34.4 21.5 18.6 28.2 35.5 33.5 32.8 30.1 18.6

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402 · Zootaxa 4683 (3) © 2019 Magnolia Press
Comparisons (Fig. 6; Table 4). Sphenomorphs preylangensis sp. nov. can be distinguished from S. stellatus by
having statistically fewer fourth toe (17–19 vs. 20–26) and fourth finger (11–14 vs. 14–18) subdigital lamellae and
having large, dark blotches as opposed to small speckles on the top of the head as well as dark transverse dorsal and
subcaudal bars/bands and black labial sutures as opposed to their absence. From S. annamiticus it is differentiated
by having statistically more paravertebral (61–68 vs. 53–62) and ventral (63–71 vs. 55–65) scales, and lacking as
opposed to having wide, dark vertebral and lateral blotches. Sphenomorphus preylangensis sp. nov. is distinguished
from S. praesignis by having statistically more infralabial scales (seven vs. six or seven, modally six) and statisti-
cally fewer midbody scale rows (24 vs. 27–30); and by the absence of large, dark anterolateral spots.
Natural history. Sphenomorphs preylangensis sp. nov. inhabits semi-evergreen forests in the vicinity of 200
m elevation (Fig. 10) where lizards are most often found on tree trunks during the day approximately 2 m above the
ground where they commonly take refuge in tree cavities. Local people cut cavities into the trunks of the trees in
order to harvest resin that accumulates within the cavities. Lizards utilize the cavities, often submerging themselves
in the resin with no apparent harm (Fig. 11). Lizards also seek shelter beneath loose bark on the trunk. CBC 02349,
however, was found in a rock crevice. Others were seen foraging among rocks during the day.
FIGURE 10. Semi-evergreen forest habitat of the type locality of Sphenomorphus preylangensis sp. nov. (CBC 2348) from
Phnom Chi, Prey Lang Wildlife Sanctuary, Cambodia. Photograph by Neang Thy.
Miscellaneous notes on Sphenomorphus annamiticus. Based on this study, it appears Sphenomorphus an-
namiticus has a disjunct circum-continental distribution along the southern and eastern hilly margins of the Indo-
chinese Peninsula from at least Khao Soi Dao, Thailand through the Cardamom Mountains of southern Cambodia
to the Bokor Plateau at the western margin of the Mekong Delta. Its distribution begins again in the lowland areas
of Ma Da and Cat Tien, Dong Nai Province on the eastern margin of the Mekong Delta in Vietnam and continues
northward to at least the type locality of Phuoc Son in Quang Nam Province (Fig. 1). Despite this, our limited ge-
netic data showed no evidence of geographically structured genetic variation nor were any such trends recovered
with the morphological data (Table 8; Fig. 3).
Little has been written concerning the natural history of Sphenomorphus annamiticus. CBC 02350 from Bokor
National Park (no. 11 in Fig. 1) was found among rocks during the day at 126 m and Stuart and Emmet (2006) report
finding FMNH 267739 (no. 10 in Fig. 1) in a pitfall trap at 200 m. LSUDPC 10975 from Khao Soi Dao Wildlife

TAXONOMY OF SPHENOMORPHUS STELLATUS AND S. PREASIGNIS Zootaxa 4683 (3) © 2019 Magnolia Press · 403
Sanctuary (no. 9 in Fig. 1) was photographed on the side of a tree at 350 m in elevation, and CUMZ 35440 was taken
from the summit of Khao Soi Dao at approximately 1550 m in elevation beneath exfoliating bark on a standing
tree (Taylor 1963). Vietnamese populations range from 80–2018 m in elevation. Darevsky & Ngyeun (1983) report
finding a specimen on the ground along the side of a road at the edge of primary forest. Vassilieva et al. (2016), who
first reported this species from lowland semideciduous forests in southern Vietnam, noted that S. annamiticus is a
very secretive, mainly terrestrial species, but sometimes was observed climbing on tree trunks. They reported their
diet to include beetles and ants (Vassilieva et al. 2016).
Miscellaneous notes on Sphenomorphus stellatus. Sphenomorphus stellatus is endemic to Peninsular Malay-
sia although it very likely ranges farther north up the Thai-Malay Peninsula to at least the Isthmus of Kra. Spheno-
morphus stellatus is rarely seen, and in fact there are only five specimens known in collections (Table 9) and only
one other vouchered sighting from Fraser’s Hill (LSUDPC 10976; no. 3 Fig. 12). Prior to this study, Grismer (2011)
reported S. stellatus from Bukit Larut, Perak (the type locality), Fraser’s Hill, Pahang, Ulu Muda, Kedah below 596
m in elevation (Norsham et al. 2005), and the Bukit Lagong Forest Reserve, Selangor at 300 m in elevation (Lim
1967). We now consider the latter two localities to be erroneous because no voucher specimens were collected for
these reports and this species is not known to occur below 1100 m. We report two new localities here from Pahang
accompanied by vouchered specimens: Cameron Highlands at 1500 m (MCZ 39283) and Genting Highlands at
1800 m (CM 65530) (Fig. 1).
Grismer (2011) reports seeing individuals moving along the ground at the edge of a house at Bukit Larut and
others (Nick Baker and Rupert Gassby-Lewis pers. comm.) have found specimens beneath pieces of wood and
within leaf litter at Fraser’s Hill. We have seen specimens 3–5 meters up on the sides of trees at the type locality
basking in sunlight (Fig. 12B) and often in pairs. These observations indicate that this species is terrestrial as well
as tree trunk-dweller.
TABLE 9. Meristic, mensural, and color pattern data of Sphenomorphus stellatus from Peninsular Malaysia. Abbrevia-
tions are listed in the Materials and methods. R = right, L = left, / = data unobtainable or not applicable.
Location in Fig. 1 1 1 1 2 4
LSUHC BMNH BMNH MCZ CM
13483 1946.8.3.26 1946.8.17.10 39283 65530
Bukit Larut Bukit Larut
syntype
Bukit Larut
syntype
Cameron
Highlands
Genting
Highlands
Elevation (m) 1100 1341 1341 1500 ~1800
Sex/maturity f / / f m
Head scales large large large large large
Head scales keeled no no no no no
Frontonasal divided no no no no no
Prefrontals in contact yes yes yes no no
Parietals contact posteriorly yes yes yes yes yes
Parietals divided no no no no no
Interparietal eye spot yes yes yes yes yes
Scales bordering posterolateral parietals 5 5 5 6 6
Nuchals 3 3 3 4 4
Supraoculars 4 4 4 4 4
Loreals 2 2 2 2 2
Anterior loreal divided no no no no no
Loreals separated from supralabials no no no no no
Postnasal groove deep absent absent absent yes absent
Superciliaries 9 8 8 9 8
Superciliary row interrupted by 4th supraocular no no no no no
Lower eyelid large scales / large scales large scales large scales
Supralabials 7 7 7 7 7
......continued on the next page

GRISMER ET AL.
404 · Zootaxa 4683 (3) © 2019 Magnolia Press
TABLE 9. (Continued)
Location in Fig. 1 1 1 1 2 4
LSUHC BMNH BMNH MCZ CM
13483 1946.8.3.26 1946.8.17.10 39283 65530
Bukit Larut Bukit Larut
syntype
Bukit Larut
syntype
Cameron
Highlands
Genting
Highlands
2nd and 3rd supralabials keeled no no no no no
Infralabials 6 6 7 6 7
1st infralabial elongate no no no no no
Chinshields 3 3 3 3 3
1° temporals 1 1 1 1 1
2° temporals 2 2 2 2 2
Upper 2° temporal large yes yes yes yes yes
Subtemporals 0 0 0 0 0
Midbody scale rows 26 23 25 26 24
Paravertebrals 64 63 62 63 63
Paravertebral scales slightly widened no no no no no
Dorsal body scales keeled or smooth smooth smooth smooth smooth smooth
Ventral scales 65 68 67 65 64
Enlarged precloacals 2 2 2 2 2
R precloacal overlapped by L yes yes no yes no
Medial cloacals enlarged / / / / /
Supracaudals smooth or keeled smooth smooth smooth smooth smooth
Scale rows at 10th subcaudal 13 / 14 14 13
Subcaudals slightly enlarged yes yes yes yes yes
4th toe lamellae 20 26 24 21 23
4th finger lamellae 15 18 17 14 16
Coloration
Wide, dark, vertebral stripe or blotches no no no no no
Wide, dark, dorsolateral stripe no no no no no
Top of head blotched or speckled speckled speckled speckled speckled speckled
Dark, transverse, subcaudal bars or blotches no no no no no
Thin, dark, dorsal, caudal bands no no weakly no no
Labial margins edged with black no no no no no
Mensural (mm)
SVL 88.0 76.6 46.6 78.2 63.5
TAL 113.0 / 64.6 / 84.9
AG 45.0 42.7 23.8 41.9 31.4
SNL 6.9 5.74 5.1 6.7 6.1
SFL 29.5 30.8 19.6 28.9 23.0
HL 20.3 17.4 12.4 17.7 15.6
HW 12.1 10.1 7.1 11.6 9.5
HH 9.7 8.5 6.4 9.5 7.8
STL 16.9 16.1 11.5 16.3 14.4
ED 4.3 5.2 3.01 4.0 3.7
ET 7.2 6.9 4.7 6.6 5.0
TD 1.7 2.2 1.5 2.1 1.6
FIL 29.8 26.8 18.0 27.4 23.5
HIL 42.9 44.1 24.8 39.9 33.7

TAXONOMY OF SPHENOMORPHUS STELLATUS AND S. PREASIGNIS Zootaxa 4683 (3) © 2019 Magnolia Press · 405
FIGURE 11. Human-made resin collecting depression cut into the side of tree (C) forming the microhabitat of a Sphenomor-
phus preylangensis sp. nov. (A and B; CBC 2403) from Phnom Chi, Prey Lang Wildlife Sanctuary, Cambodia. B. The skink is
actually submerged in the resin. Photographs by Neang Thy.

GRISMER ET AL.
406 · Zootaxa 4683 (3) © 2019 Magnolia Press
FIGURE 12. Sphenomorphus stellatus from Peninsular Malaysia. A. LSUDPC 10976 subadult from Fraser’s Hill, Pahang.
Photograph by Kurt Orion. B. In situ photograph of LSUDPC 9721 from Bukit Larut, Perak. Photograph by L. L. Grismer.

TAXONOMY OF SPHENOMORPHUS STELLATUS AND S. PREASIGNIS Zootaxa 4683 (3) © 2019 Magnolia Press · 407
Discussion
The discovery of multiple species within the widely distributed Sphenomorphus stellatus sensu lato is not surprising
as it mirrors the taxonomic results of many recent and ongoing studies of Indochinese and Sundaic species com-
plexes (e.g. Stuart et al. 2006; Malhotra et al. 2011; Sheridan & Stuart 2018; Grismer et al. 2019b; Hartmann et al.
2013; Geissler et al. 2015a; Poyarkov et al. 2017, 2019; Chen et al. 2018; Murdoch et al. 2019). It was surprising,
however that there was no clear phylogeographic substructuring in S. annamiticus on opposite sides of the Mekong
Delta as this area has been shown to harbor and generate a number of endemic species (e.g. Grismer and Ngo 2007;
Grismer & Grismer 2017; Nguyen et al. 2018) and the Mekong Valley is often regarded as an important biogeo-
graphic barrier for herpetofauna (Bain & Hurley 2011; Geissler et al. 2015b). The discovery of S. preylangensis sp.
nov. continues to underscore the high degree of site-specific endemism in isolated hilly regions within the Indochi-
nese Peninsula (e.g. Bain & Hurley 2011; Chan-ard et al. 2015; Murdoch et al. 2019) and the need for additional
field research throughout these insular habitats.
Conservation
Much of the following comes from an unpublished Biodiversity Assessment Report by Hayes et al. (2015). The Prey
Lang Wildlife Sanctuary (PLWS) stretches over the provinces of Kratie, Kampong Thom, Stung Treng and Preah
Vihear and lies within three watersheds—the Stung Sen, Stung Chinit and Siem. It traverses the hydrological divide
between the Tonle Sap and Mekong Basins and contains one of the largest remnants of Cambodia’s once vast, wet,
lowland evergreen forest which composes part of the Indo-Burma Hotspot (Myers et al. 2004). Across all areas of
Prey Lang, there is considerable habitat degradation. The high diversity and relatively high proportion of globally
threatened species of amphibians and reptiles found in the PLWS are critically important as they are the indicators
of a healthy environment (Hartwell et al. 1998). Currently, the herpetofauna is threatened by many unsustainable
activities, the most severe of which are the conversion of forest for settlement, agriculture and development, and
habitat fragmentation by the construction of infrastructure. Past and current selective logging have changed the for-
est composition and structure, altering the microclimate and increasing sedimentation in hydrological systems. This
leads to shallower water regimes and unfavorable conditions for breeding and shelter for water dependent species.
Based on conversations with local people by Neang Thy, professional poachers and loggers in developed areas
supplement their diet with large-bodied amphibians such as Hylarana mortenseni (Boulenger), Hoplobatrachus
rugulosus (Wiegmann) and Kaloula pulchra Gray while reptiles are collected for both bush meat and trade. Vara-
nus bengalensis (Daudin) were observed hanging in stores for sale in Boeung village at Prey Lang and a number
of Physignathus cocincinus Cuvier were seen being carried by local hunters during a survey in August 2014. The
Reticulated Python (Malayopython reticulatus Schneider) and all turtle species in the area are reportedly hunted for
both local consumption and trade, according to people from Siem Bok, Srepring, and Chhvang. Sphenomorphus
preylangensis sp. nov. is the first endemic species of reptile to be described from Prey Lang and it is hoped that its
presence increases the needed conservation profile of the area. Continued field work is likely to recover additional
yet-undiscovered species.
Acknowledgements
We would like to thank the following museum curators for the loan of specimens: Valentina F. Orlova (ZMMU
R); Natalia Ananjeva and Konstantin Milto (ZISP); Alan Resetar (FMNH); and Patrick Campbell (BMNH). For
field assistance in Malaysia, we thank Anthony Cobos, and we are also grateful to the Department of Wildlife and
National Parks, Peninsular Malaysia for issuing a research permit (P-00074-15-18). We thank Eduard Galoyan
(ZMMU), Anna Vassilieva (Severtsov Institute of Ecology and Evolution RAS) and Peter Geissler (Museum Natur
und Mensch, Freiburg) for support. We thank Adam Henson for his help in facilitating the delivery of tissue mate-
rial from Cambodia. We thank Hinrich Kaiser for the translation of Boettger (1901) and helping us to determine the
type locality and color pattern of the syntypes of Sphenomorphus annamiticus. This paper is contribution number
901 of the Auburn University Museum of Natural History. This work was carried out with financial support from the

GRISMER ET AL.
408 · Zootaxa 4683 (3) © 2019 Magnolia Press
Russian Science Foundation (RSF grant № 19-14-00050 to NAP, molecular analyses) and was partially supported
by RFBR grants No. 19-54-54003 Viet to NLO.
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