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The present-day vertebrate fauna of Tonga contains 17 species of lizards from three families: Gekkonidae, Iguanidae, and Scincidae. Are any of these lizard species members of a fauna before humans arrived? This question is examined and partially resolved. Endemic taxa, such as Lepidodactylus euaensis, Emoia adspersa, and E. tongana, are likely inhabitants whose ancestors arrived, before the arrival of humans, via waif dispersal and subsequently differentiated in isolation. Recognition of these species is essential to interpret correctly the evolutionary history of the Tongan herpetofauna. The largest surviving Tongan skink previously has been identified incorrectly as a population of the Fijian Emoia trossula lineage. It is not and, herein, is differentiated from Emoia trossula and other central Pacific members of the Emoia samoensis species group and subgroup. Emoia mokolahi Zug, Ineich, Pregill & Hamilton, n. sp., differs from its sister taxa in the Emoia samoensis species subgroup by body size, dorsal and digital scalation, and coloration.
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Lizards of Tonga with Description of a New Tongan Treeskink
(Squamata: Scincidae: Emoia samoensis Group)
Author(s) :George R. Zug, Ivan Ineich, Gregory Pregill, and Alison M. Hamilton
Source: Pacific Science, 66(2):225-237. 2012.
Published By: University of Hawai'i Press
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Pacific Science (2012), vol. 66, no. 2:225 237
© 2012 by University of Hawai‘i Press
All rights reserved
The extant Tongan lizard fauna consists
of eight geckos, eight skinks, and an iguana
(Table 1). A large terrestrial, likely semifosso-
rial, skink (Tachygyia microlepis) is presumably
extinct (Ineich and Zug 1996). The first and
only record of this Tongan lizard is from
the early nineteenth-century report of the
L’Astrolabe expedition (Dumont d’Urville
1832) when they were discovered. During the
expedition’s around-the-world scientific ex-
ploration, it spent a month on Tongatapu in
1827 and brought two specimens back to
P aris. This large, reduced-limbed lizard was
described subsequently as Eumeces microlepis
by Duméril and Bibron (1839) and has never
been seen again in the Islands, hence known
only by the two syntypes. Other lizards oc-
curred in the Tonga archipelago but disap-
peared shortly after the arrival of the Polyne-
sians (Pregill and Dye 1989). An archeological
excavation in the Hai‘apai group revealed the
remains of an iguana, significantly larger than
the iguana (Brachylophus fasciata) currently oc-
curring in the Tongatapu group. This extinct
iguana was subsequently described (Pregill
and Steadman 2004) as Brachylophus gibbonsi.
Lizards of Tonga with Description of a New Tongan Treeskink
(Squamata: Scincidae: Emoia samoensis Group)1
George R. Zug,2,6 Ivan Ineich,3 Gregory Pregill,4 and Alison M. Hamilton5
Abstract: The present-day vertebrate fauna of Tonga contains 17 species of
lizards from three families: Gekkonidae, Iguanidae, and Scincidae. Are any of
these lizard species members of a fauna before humans arrived? This question is
examined and partially resolved. Endemic taxa, such as Lepidodactylus euaensis,
Emoia adspersa, and E. tongana, are likely inhabitants whose ancestors arrived,
before the arrival of humans, via waif dispersal and subsequently differentiated in
isolation. Recognition of these species is essential to interpret correctly the
e volutionary history of the Tongan herpetofauna. The largest surviving Tongan
skink previously has been identified incorrectly as a population of the Fijian
Emoia trossula lineage. It is not and, herein, is differentiated from Emoia trossula
and other central Pacific members of the Emoia samoensis species group and sub-
group. Emoia mokolahi Zug, Ineich, Pregill & Hamilton, n. sp., differs from its
sister taxa in the Emoia samoensis species subgroup by body size, dorsal and digital
scalation, and coloration.
1 Research supported by Smithsonian Visiting Schol-
ars program and Action Transversal du MNHN (ATM)
“Biodivesité actuelle et fossile” to I.I.; National Geo-
graphic Society 5032-93, University Professorship Uni-
versity of San Diego for G.P.; National Science Founda-
tion (DEB 0408010, DEB 0445213, DBI 0400797) to
Christopher C. Austin and A.M.H.; an EPSCoR Fellow-
ship to A.M.H.; grants from Graduate Women in Sci-
ence, American Society of Ichthyologists and Herpetolo-
gists, Society for the Study of Amphibians and Reptiles,
Sigma Xi (LSU chapter), and Louisiana State University
(Museum of Natural Science and BioGrads) to A.M.H.;
and the National Geographic Society, Smithsonian
Scholarly Studies Program, and NMNH-Research Op-
portunities Fund to G.R.Z. Manuscript accepted 30 June
2 Department of Vertebrate Zoology, National Mu-
seum of Natural History, Smithsonian Institution, Wash-
ington, D.C. 20013.
3 Département Systématique & Evolution, Muséum
national d’Histoire naturelle, UMR 7205 (OSEB), CP30,
25 rue Cuvier, 75005 Paris, France (e-mail: ineich@
4 Department of Biology, University of San Diego,
5998 Alcala Park, San Diego, California 92110 (e-mail:
5 Department of Ecology and Evolutionary Biology,
University of California, Los Angeles, California 90095
6 Corresponding author (e-mail:
226 PACIFIC SCIENCE · April 2012
The extinction of these two large species and
possibly also smaller lizard species generates
several questions.
What was the lizard fauna of the Tongan
Islands before humans arrived? We examine
this question subsequently in our Biogeo-
graphic Comments; however, we realize that
our present-day faunal data set of extant liz-
ards and those that arrived before humans is
inadequate and will provide an incomplete
answer. Closely associated with this primary
question is how many components of the cur-
rent lizard fauna are members of the fauna
before human arrival? One hypothesis is that
species endemic or indigenous to the Tongan
Islands represent natural dispersal events,
whose populations had thousands or more
years to differentiate and adapt before the
a rrival of the first human settlers. Another
possibility is that one or more of the Tongan
endemics occurred more broadly in the cen-
tral Pacific but is now restricted to Tonga. A
third hypothesis is that widespread Pacific
species and species that are largely genetically
uniform over wide reaches of Oceania are re-
cent dispersants, arriving with or subsequent
to the first human settlers. We will examine
these propositions later.
Extant Terrestrial Reptiles of Tonga
Taxa Island and Island Groups
Gekkonidae Niuafo‘ou Niuatoputapu Vava‘u Ha‘apai Tongatapu ‘Eua
Gehyra insulensis ——++
Gehyra oceanica
Hemidactylus frenatus ——++
Hemidactylus garnotii ——+
Hemiphyllodactylus typus ——+——+
Lepidodactylus euaensis ——+
Lepidodactylus lugubris ++++++
Nactus pelagicus ——++ + +
Brachylophus fasciatus
Cryptoblepharus poecilopleurus +++ + +
Emoia adspersa +——
Emoia cyanura ++++++
Emoia impar ++++++
Emoia nigra ++—— +c
Emoia mokolahi ——++ + +
Emoia tongana ++++——
Lipinia noctua ++++++
Sources: Gill (1987, 1990), Gill and Rinke (1990), Gill et al. (1994), Zug and Gill (1997), Zug and Ineich field notes 1992 (Ton ga-
tapu, ‘Eua), 1993 ( Vava‘u, Ha‘apai, Tongatapu).
Note: Symbols: —, no museum voucher specimens or reliable literature records; +, occurrence confirmed by museum voucher
specimens or reliable literature records.
a The presence of Gehyra vorax in Tonga was proposed tentatively by Beckon (1992:450): “Fiji and perhaps Tonga (Fig. 5).” He saw
no Tongan G. vorax specimens, and no specimens with unquestionable Tongan locality data exist. A recent proposal for a Society Island
occurrence was based on specimens with questionable locality data.
b Pregill and Steadman (2004) argued for the Tongan B. fasciatus as a pre-European introduction from the Lau group. Their argu-
ment is strong owing to the absence of subfossil B. fasciatus in Tonga in contrast to its abundance as subfossils in the Lau group of islands
(Steadman et al. 2002), and the molecular identity of the Tongan iguanas demonstrating their origin from Lau iguanas ( Keogh et al.
c The Natural History Museum, London, collection ( BMNH) contains specimens of Emoia nigra and E. lawesi ( BMNH,, respectively) with Tongatapu locality datum. The occurrence vouchered by these specimens has been not confirmed by any
recent (since the 1950s) herpetological fieldwork. Darevsky and Orlov (1994 [1993]) reported E. atrocostata and E. caeruleocauda from
Niuafo‘ou; those records are considered erroneous because of other peculiarities associated with their species identifications from
other Pacific island groups (Zug 1991:10); however, we accept their Niuafo‘ou records of E. cyanura, a sample of which included E.
impar, because those vouchers were examined and identity confirmed (I.I.).
Lizards of Tonga · Zug et al. 227
Because our biogeographic questions re-
quire the resolution of the origins of Tongan
lizards, we demonstrate the unique status of
the largest surviving Tongan treeskink. This
skink is currently recognized as a population
of the putatively widespread central Pacific
Emoia trossula. Our field observations revealed
that the Tongan E. “trossula” differed in ap-
pearance from individuals of the various F ijian
and Samoan populations. Subsequently, phy-
logenetic analysis of a mitochondrial and nu-
clear DNA data set (Hamilton et al. 2010: fig.
2) revealed that the Tongan “trossula” was a
member of a large clade composed of Samoan
and Fijian populations, yet was genetically
quite distinct from other populations. The
Tongan population represents a basal or early
divergence within a Samoan-Fijian clade
(Figure 1) and indicates an early arrival and
subsequent in situ speciation within the Ton-
gan archipelago. This Samoan-Fijian sister
group contains several distinct genetic lin-
eages. The taxonomy of these lineages will be
addressed in subsequent reports.
Figure 1. A schematic cladogram showing relationships of Emoia mokolahi to its nearest sister-group relatives in the
South-central Pacific. All listed populations are members of the Emoia samoensis species subgroup. This cladogram
derives from a phylogeny constructed using Maximum Likelihood and Bayesian Inference on a mitochondrial and
nuclear DNA data set (Hamilton et al. 2010: fig. 2).
228 PACIFIC SCIENCE · April 2012
materials and methods
The large Tongan skink has mistakenly been
identified with Fijian Emoia trossula largely
because of its large size and general color-
ation. Its affinities (Figure 1) are with mem-
bers of the E. samoensis subgroup, and it is
with those taxa that the Tongan skink is com-
pared and differentiated (Appendix).
Our character set contains 13 mensural
and 20 scalation (meristic) characters, al-
though not all characters are reported herein.
Sex and maturity were determined by exami-
nation of gonads. Locality data for the exam-
ined specimens are in the Appendix. All
m ensural characters are straight-line mea-
surements of body segments to the nearest 0.1
mm with dial calipers. Scalation features of
head, body, and limbs were recorded from the
right side on paired features. All statistical
analyses were performed with SYSTAT 11.
Sexual dimorphism among adults was tested
by Student’s t tests (P < .05).
The character set is an expansion of the set
defined in a study of morphological variation
of Emoia tongana (Zug and Gill 1997) and
s ubsequently expanded and new characters
defined in the description of Emoia tuitarere
(Zug et al. 2011). The following lists provide
character names and their abbreviations.
Measurements: Eye ear length (EyeEar);
head height (HeadH); head length (HeadL);
hindlimb length (HindlL); interorbital width
(Interorb); jaw width ( JawW ); naris eye
length ( NarEye); snout – eye length (SnEye);
snout width (SnW ); snout forelimb length
(SnForel); snout vent length (SVL); tail
length (TailL); trunk length (TrunkL). Scala-
tion: Anterior loreal shape (AntLor); au-
ricular lobes, number (AuricL); dorsal body
scales, number (Dorsal); eyelid scales, number
(Eyeld); frontoparietal scale (Frontpa); infra-
la bial scales, number (Inflab); interparietal
scale, present or absent (Interpa); keeling of
body scales, number of keels (DorsKN,
L atKN, VntlKN ); loreal scales, number
(Lor); midbody scale rows, number (Mid-
body); nuchal scales, number of pairs ( Nu-
chal); precloacal scales size (Precl); prefrontal
scales, in contact or not (Prefr); subdigital
l amellae, number on fourth finger (4FingLm)
and on fourth toe (4ToeLm); supralabial
scales, number (Suplab); supralabial scale
b elow orbit (BlwEye); supraocular scales,
number (Suproc); supraciliary scales, number
taxonomic results
Emoia mokolahi Zug, Ineich, Pregill & Hamil-
ton, n. sp.
Figures 2, 3
type material. Holotype: USNM 333684,
adult female from Kingdom of Tonga, Vava‘u
group, Vava‘u (Island), approximately 1 km
W of Neiafu (18° 39 S, 173° 59 W ), south
side of Mt. Talau, collected by George R.
Zug, 10 November 1993.
Paratypes: All specimens from the King-
dom of Tonga. Vava‘u group: AIM LH1304,
Vava‘u (Island) near Holonga, by B. J. Gill, 27
September 1989; AIM LH1312, Vava‘u (Is-
land) near Sia Ko Kafoa, by B. J. Gill, 28 Sep-
tember 1989; CAS 158241, USNM 259331
259332, Vava‘u (Island), by J. R. H. Gibbons,
January 1985. Ha‘apai group: AMNH 40567
40568, Tonomaia (Island) [=Tonumeai 20°
28 S, 174° 46 W], by Rollo H. Beck, 18 July
1925; USNM 333763, Lifuka (Island), 1.5 2.0
km ESE of Pangai, by G. R. Zug, 14 Novem-
ber 1993; USNM 333764, Lifuka (Island), Point
Port au Prince, by G. R. Zug, 15 November
1993. Tongatapu group: AMS R116162, Ton-
gatapu (Island), Euaiki Island, east of Ton-
gatapu (21° 7 S, 174° 58 W ), H. G. Cogger,
10 November 1984; CAS 159999, Tongatapu
(Island), Toloa forest, by M. Miller, 20 Feb-
ruary 1986; USNM 333577, Tongatapu (Is-
land), ca. 2 km W of Kolovai, by G. R. Zug,
19 November 1993. ‘Eua: AMS R96577 – R96578
‘Eua Island, Tonga group (21° 23 S, 174° 57
W ), H. Ehmann, 10 May 1980; AMS R96584,
‘Eua Island, Tonga group (21° 23 S, 174° 57
W ), H. Ehmann, 10 May 1980; CAS 158245,
‘Eua (Island), by J. R. H. Gibbons, January
1985; CAS 159407 159408, ‘Eua (Island), by
J. R. H. Gibbons, 19 20 October 1985; FMNH
191762, ‘Eua (Island), by N. L. H. Kraus, 24
February 1972; SDSNH 66147, ‘Eua (Island), 2
km E of Houma village, by G. K. Pregill, 21
November 1987; USNM 259333, ‘Eua (Island),
Lizards of Tonga · Zug et al. 229
by J. R. H. Gibbons, January 1985; USNM
322228, ‘Eua (Island), 0.5 2.0 km W of Pan-
gai, by I. Ineich and G. R. Zug, 9 October
1992; USNM 322229, ‘Eua (Island), 2 6 km E
and SE of Petani, by I. Ineich and G. R. Zug,
10 October 1992; USNM 322230, ‘Eua (Island),
0.5 2.5 km W of Pangai, by I. Ineich and
G. R. Zug, 12 October 1992.
Juvenile females: AMS R116262, FMNH
191762, USNM 259333; juvenile males: USNM
322228, 333763 333764; unsexed juvenile:
USNM 322229; adult females: AIM LH1304,
AMS R96577, R96584, CAS 158241, 158245,
159407; adult males: AIM LH1312, AMNH
40567 – 40568, AMS R96578, CAS 159408,
159999, SDSNH 66147, USNM 259331 – 259332,
322230, 333577.
diagnosis. Emoia mokolahi is a member
of the Emoia samoensis species group and the
samoensis subgroup (Zug et al. 2011). Emoia
mokolahi differs from other subgroup mem-
bers by a combination of traits. Emoia moko-
lahi females average (mean 96 mm, range
86 105 mm SVL) larger than E. tuitarere fe-
males (81 mm, 72 93 mm) (Table 2) and the
E. trossula type-series females (90 mm, 87 101
mm), and smaller than Samoan E. samoensis
females (97 mm, 86 109 mm) and Vanuatuan
E. sanfordi females (103 mm, 97 109 mm). In
female scalation, E. mokolahi averages more
dorsal scales [Dorsal] (65, 62 69) than E. san-
fordi (58, 56 61) and Samoan E. samoensis (63,
62 – 66); E. mokolahi has fewer 4th-finger la-
mellae [4FingLm] (34, 32 36) than E. sanfordi
(47, 43 51) and E. tuitarere (37, 36 40) and
fewer 4th-toe lamellae [4ToeLm] than E. san-
fordi (66, 57 71) and E. tuitarere (49, 47 51).
description of holotype. An adult
f emale, 97.9 mm SVL (103.9 mm in life),
136 mm TailL (135 mm in life, two-thirds
Figure 2. A paratype of Emoia mokolahi, n. sp., USNM 322230, from ‘Eua. A, Dorsal view of head; B, lateral view of
head; C, ventral view of right hind foot.
230 PACIFIC SCIENCE · April 2012
r egenerated), 48.1 mm TrunkL, 34.1 mm
S nForel, 44.8 mm HindlL, 20.3 mm HeadL,
13.4 mm JawW, 9.8 mm HeadH, 8.6 mm
S nEye, 6.8 mm NarEye, 7.9 mm EyeEar, 3.7
mm SnW, and 7.2 mm Interorb. Body pro-
portions: 49% TrunkL/SVL, 46% HindlL/
SVL, 35% SnForel/SVL, 21% HeadL/SVL,
and 9% S nEye/SVL.
Scalation right side for bilateral traits:
modest-sized semilunate rostral posteriorly
contacting 1st supralabial, anterior n asal, elon-
gate rectangular supranasal and medially large
pentagonal frontonasal; large r ectangular pre-
frontals with moderate contact medially, large
elongate pentagonal frontal, large hexagonal
frontoparietal, elongate triangular interpari-
etal (with distinct parietal eye) separating paired
large rectangular parietals except posteriorly,
large paired nuchals; 4 Supoc 1st and 2nd sub-
equal in area and largest Supoc, 8 Supcil, 10
Eyeld, horizontal elliptical palpebral disk about
one-third area of lower eyelid; large circular
naris dividing nasal into equal-sized anterior
and posterior halves, AntLor nearly square
and posterior loreal longer than high, two
l oreals subequal in area, 2 p reoculars and 1
subocular on anterior margin of orbit, double
row of postoculars with dorsalmost one l argest,
2 modest-sized primary temporals, lower
twice size of upper, 2 large secondary tempo-
rals, upper twice size of lower; 8 Suplab, 6th
BlwEye, 8 Inflab, moderate nearly circular ear
opening with 4 blunt-triangular AuricN on
anterior border; 66 smooth Dorsal, 33 Mid-
body, 35 smooth 4FingLm, 48 4ToeLm, and
precloacal scale distinctly enlarged.
Coloration in life: Dorsally head unicolor
coppery brown merging into brown with
Summary of Select Mensural Characters (Mean ± Standard Deviation and Range) in Central Pacific Samples of
Adult Members of the Emoia samoensis Species Group Taxa
Taxon SVL HeadL
Emoia mokolahi (Tonga)
Females [8] 96.2 ± 6.50 20.2 ± 1.03* 0.50 ± 0.027 0.47 ± 0.026 0.35 ± 0.017 0.21 ± 0.006*
86.0 – 105.2 18.8 – 21.5 0.46 – 0.55 0.45 – 0.53 0.32 – 0.36 0.20 – 0.22
Males [11] 96.9 ± 4.60 21.9 ± 1.15* 0.48 ± 0.024 0.49 ± 0.026 0.37 ± 0.024 0.23 ± 0.006*
90.5 – 103.7 19.5 – 23.3 0.44 – 0.51 0.43 – 0.52 0.34 – 0.40 0.21 – 0.24
Emoia samoensis (Samoa)
Females [13] 97.2 ± 5.55 21.2 ± 1.29* 0.49 ± 0.027* 0.47 ± 0.028* 0.37 ± 0.024 0.22 ± 0.011*
84.3 – 108.8 19.9 – 24.7 0.44 – 0.53 0.43 – 0.54 0.34 – 0.43 0.21 – 0.25
Males [15] 100.0 ± 7.64 23.1 ± 1.83* 0.48 ± 0.015* 0.48 ± 0.022* 0.37 ± 0.021 0.23 ± 0.010*
86.8 – 111.9 20.0 – 25.7 0.46 – 0.51 0.45 – 0.52 0.34 – 0.41 0.22 – 0.25
Emoia sanfordi ( Vanuatu)
Females [11] 102.8 ± 4.49 22.4 ± 0.82* 0.49 ± 0.017 0.43 ± 0.024* 0.35 ± 0.015* 0.22 ± 0.005*
96.9 – 110.5 21.3 – 23.9 0.46 – 0.52 0.41 – 0.48 0.33 – 0.38 0.21 – 0.22
Males [8] 102.0 ± 7.10 24.7 ± 1.92* 0.49 ± 0.032 0.47 ± 0.028* 0.37 ± 0.022* 0.24 ± 0.011*
91.8 – 114.8 22.5 – 26.9 0.42 – 0.54 0.43 – 0.51 0.34 – 0.40 0.23 – 0.26
Emoia trossula (type series
Females [11] 90.2 ± 7.48 20.2 ± 2.19 0.48 ± 0.031 0.48 ± 0.031 0.38 ± 0.019 0.22 ± 0.010*
87.0 – 101.2 17.4 – 24.9 0.45 – 0.55 0.45 – 0.55 0.36 – 0.41 0.21 – 0.25
Males [18] 90.9 ± 8.53 21.2 ± 2.16 0.46 ± 0.02 0.49 ± 0.034 0.38 ± 0.020 0.23 ± 0.008*
75.9 – 102.4 17.0 – 24.2 0.42 – 0.50 0.40 – 0.55 0.35 – 0.43 0.22 – 0.25
Emoia tuitarere (Cook Islands)
Females [13] 80.8 ± 5.49 17.5 ± 0.80* 0.49 ± 0.019* 0.47 ± 0.031* 0.36 ± 0.017* 0.22 ± 0.010*
72.0 – 92.6 16.3 – 19.3 0.46 – 0.52 0.42–0.53 0.33 – 0.38 0.20 – 0.24
Males [9] 83.7 ± 7.06 19.6 ± 1.50* 47.0 ± 0.015* 0.50 ± 0.030* 0.38 ± 0.015* 0.23 ± 0.004*
67.5 – 93.0 16.1 – 21.3 0.45 – 0.49 0.45 – 0.53 0.36 – 0.40 0.23 – 0.24
Note: *, Denotes statistically significant sexual dimorphism (Student t, P .05). Sample size in brackets; SVL and HeadL in mm.
a Excludes the Rotuma specimens; main Fiji Islands only.
Lizards of Tonga · Zug et al. 231
t arnished copper tint on neck, trunk, and tail,
from midneck to base of tail a series of short
longitudinal dark-edged streaks of cream and
infrequent small dark brown spots; streaks
a rranged in about nine transverse series with
five to six streaks per series and streaks b ecome
shorter and more irregularly arranged after
midbody, streaks confined to dorsal surface;
laterally three modest-sized dark brown spots,
one on neck, another above shoulder, and
nal one on anterior trunk; dorsally limbs
uniform brown of dorsum. Uniform brown of
top of head extends ventrally on upper lips in
front of eye; posteriorly and below eye diffuse
cream with a dusky blotch at upper corner of
jaw; eyelids’ edges coppery brown. Latero-
ventrally neck and trunk lighten and merge
into cream-colored venter with orange high-
lights, chin to anterior chest immaculate, dark
speckling begins behind axilla and continues
on to base of tail. Undersides of limbs lighter
colored than venter and underside of manus
and pes bright yellow.
Coloration in preservative: Coloration is
modestly muted by preservation. Pattern of
dark and light markings unchanged. Dorsal
ground color retains coppery brown back-
ground, venter with light olive cast, limbs re-
main uniform cream.
description. A large Emoia ranging in
adult size from 86 to 105 mm SVL, females
86.0 – 105.2 mm (adult Ƃ, n = 8); males 90.5
103.7 mm (adult ƃ, n = 11) with HeadL
18.8 – 21.5 mm (Ƃ) 19.5 23.3 mm (ƃ), JawW
10.2 – 13.9 mm (Ƃ) 12.7 15.9 mm (ƃ), HeadH
8.7 – 9.9 mm (Ƃ) 9.3 11.5 mm (ƃ), SnEye
8.3 – 9.8 mm (Ƃ) 8.8 10.9 mm (ƃ), NarEye
5.9 – 7.0 mm (Ƃ) 6.3 8.1 mm (ƃ), EyeEar
6.4 – 12.3 mm (Ƃ) 6.9 12.2 mm (ƃ), SnW
3.3 – 3.7 mm (Ƃ) 2.8 3.8 mm (ƃ), Interorb
7.0 – 7.9 mm (Ƃ) 7.0 8.8 mm (ƃ), SnForel
32.9 – 34.4 mm (Ƃ) 31.7 40.4 mm (ƃ),
TrunkL 42.1 55.6 mm (Ƃ) 40.9 52.5 mm
(ƃ), and HindlL 42.4 47.7 mm (Ƃ) 41.1 54.1
mm (ƃ).
Emoia mokolahi is sexually dimorphic in
most mensural features of the head, with only
EyeEar and SnW monomorphic between
adult females and males. Males are larger than
females in all other head metrics. In contrast,
none of the body metrics is dimorphic. Males
average slightly larger (96.9 mm SVL) than
females (96.2 mm), although the means
are not significantly different, similarly for
TrunkL (48.1, 46.5 mm; means females
[n = 8], males [11], respectively), HindlL
(45.3, 47.7 mm), and SnForel (33.8, 36.2
mm). Only two proportions show significant
dimorphism: HeadL/SVL (21, 23%) and
S nEye/SVL (9.8, 10.0%). The nondimorphic
metrics are TrunkL/SVL (50, 48%), HindlL/
SVL (47, 49%), HindlL/TrunkL (95, 103%),
SnForel/SVL (35, 37%), JawW/HeadL (63,
65%), NarEye/SnEye (75, 75%), EyeEar/
S nEye (107, 89%), and SnW/HeadL (17,
None of the scalation traits displays or sug-
gests sexual dimorphism (Table 3). The inter-
parietal is always present, frontoparietal al-
ways single, and prefrontals usually in contact;
4 Supoc, 8 (uncommonly 7 or 9) Supcil, 9 15
Eyeld, 8 (rarely 9) Suplab, 6th (rarely 7th)
BlwEye, and 7 (uncommonly 8) Inflab on
each side. Palpebral disk small, about one-
fourth to one-third area of lower eyelid area;
moderate-sized, oblong vertical (occasionally
oblique) ear opening with 0 5 (median 2)
A uricN, usually blunt, on anterior margin.
Trunk scales usually smooth, uncommonly
weakly tricarinate or striated dorsally and lat-
erally, with 58 72 Dorsal (median 64), single
pair of Nuchal, 30 36 Midbody (34). Subdig-
ital lamellae smooth, 29 38 4FingLm (34),
42 52 4ToeL (47).
Variation is relatively low in most m ensural
and meristic traits, typically V 10 for men-
sural ones and <6 for meristic ones. This low
variation suggests the presence of little or in-
significant morphological variation among
the four island groups ( Vava‘u, Ha‘apai, Ton-
gatapu, ‘Eua). Unfortunately, although we
were able to test for intra-archipelago varia-
tion in the nondimorphic meristic traits, our
adult sample sizes were too small for testing
dimorphism in mensural traits. Of the meris-
tic traits, nine have sufficient variation to
demonstrate potential interisland variation.
Six (Pref, Suprcil, Eyeld, AntLor, AuricL,
Midbody) have identical or near identical (1)
medians. The greatest difference among is-
land populations is seen in the 4ToeLm trait.
The Ha‘apai sample (n = 4) has a 44 4ToeLm
232 PACIFIC SCIENCE · April 2012
median, whereas the other three localities
( Vava‘u [n = 8)], Tongatapu [9], ‘Eua [10])
have medians of 47 or 48.
There is a slight indication of interisland
difference in coloration (here dependent
upon coloration in alcoholic specimens). The
ground color of adults from Vava‘u to ‘Eua is
a medium brown, usually with a coppery
sheen, most evident anteriorly. The top of the
head and anterodorsal portion of the neck is
unicolor. Adults from Vava‘u (Figure 3B)
have the fewest dark brown markings on the
neck and trunk. The first dorsal dark mark-
ings occur above the shoulders as small dark
streaks and these occur sporadically on the
anterior two-thirds of the trunk. Bright light
yellow to cream streaks lie in transverse series
from the base of the neck onto the base of the
tail; the streaks gradually become shorter and
fewer in each series posteriorly. Laterally, a
diffuse dark smudge occurs in the temporal
area; a small but well-defined dark spot lies
midway between ear opening and axilla; a di-
agonally vertical, dark, linear spot is over the
axilla; and no dark spots occur on the sides of
the trunk. The venter bears numerous widely
scattered dark flecks (dark scales) from chest
onto the base of the tail.
We have two adult males in our Ha‘apai
sample and one adult male from Tongatapu.
The Ha‘apai males are preservative darkened
and the pattern is masked. The Tongatapu
male has a few paired dark spots on the dor-
sum and a series of four widely spaced dark
spots laterally on the trunk; the shoulder,
midneck, and temporal marks are similar to
those of Vava‘u specimens. The Tongatapu
males lack the elongate yellow streaks on the
dorsum and instead have a few dull yellow
spots (single scale in size) on the shoulder and
Summary of Select Scalation Characters (Median ± Standard Deviation and Range) in Central Pacific Samples of
Adult Members of the Emoia samoensis Species Group Taxa
Taxon Dorsal Midbody 4FingLm 4ToeLm
Emoia mokolahi (Tonga)
Females [8] 64.5 ± 2.2 33.5 ± 1.2 34 ± 1.2 47.5 ± 2.1
62 – 69 32 – 34 32 – 36 44 – 50
Males [11] 65 ± 4.4 34 ± 1.6 33 ± 2.2 46 ± 2.8
58 – 72 30 – 36 29 – 38 43 – 52
Emoia samoensis (Samoa)
Females [13] 63 ± 1.5 31 ± 1.1* 33 ± 1.2 47 ± 2.4*
62 – 66 30 – 33 31 – 35 44 – 51
Males [15] 63 ± 1.6 32 ± 0.8* 33 ± 1.3 45 ± 1.8*
60 – 65 31 – 34 31 – 35 42 – 48
Emoia sanfordi ( Vanuatu)
Females [11] 58 ± 1.8 31 ± 0.9 47 ± 2.6 66 ± 4.0
56 – 61 30 – 32 43 – 51 57 – 71
Males [8] 58 ± 1.1 31 ± 0.9 48 ± 1.8 66.5 ± 2.2
57 – 60 30 – 32 46 – 51 63 – 69
Emoia trossula (type series
Females [11] 65 ± 2.7 34 ± 1.4 33 ± 2.2 47 ± 3.7
62 – 71 31 – 36 30 – 37 42 – 55
Males [18] 65 ± 3.0 33 ± 1.5 33.5 ± 2.5 46.5 ± 3.4
59 – 70 31 – 36 30 – 38 41 – 55
Emoia tuitarere (Cook Islands)
Females [13] 65 ± 2.3 32 ± 1.0 37 ± 1.4 49 ± 1.0
62 – 69 32 – 35 36 – 40 47 – 51
Males [9] 64 ± 1.1 33 ± 0.9 36 ± 2.6 50 ± 2.3
62 – 65 32 – 34 34 – 42 46 – 53
*, Denotes statistically significant sexual dimorphism (Student t, P .05). Sample size in brackets.
a Excludes the Rotuma specimens; main Fiji Islands only.
Lizards of Tonga · Zug et al. 233
anterior one-third of the trunk. The venter is
yellowish green from the base of the throat
onto the underside of the tail; chin to throat is
ivory; and numerous dark flecks occur from
chin onto tail. ‘Eua adults (Figure 3A) are
similar to the Tongatapu pattern, although
with more numerous dark spots on the dor-
sum and sides of the trunk; the yellow flecking
is also reduced and dull. The venter color-
ation is as in Tongatapu adults. Juvenile to
subadult patterns match those of adults, per-
haps brighter. The two Ha‘apai juveniles have
a pattern similar to the adult pattern described
here for Vava‘u.
distribution. Emoia mokolahi is wide-
spread in the Tongan Islands, extending in
the north from the Vava‘u group to ‘Eua in
the south. There are no records from the
northern outliers of Niuafo‘ou and Ni-
uatoputapu, although Emoia tongana occurs
etymology. The specific name derives
from two Tongan words, lahi (adjective) for
big and moko (noun) for lizard, hence mokolahi
(following Tongan word order) refers to this
taxon being the largest extant skink in the
Tongan Islands. It is proposed as a noun in
Comparison with samoensis Subgroup Taxa
Currently, there are five named species in the
samoensis subgroup: mokolahi (Tonga), samo-
ensis (Samoa and Fiji), sanfordi ( Vanuatu), tros-
sula (Fiji), and tuitarere (Cook Islands). The
major differences between E. mokolahi and the
other four are detailed in the preceding Diag-
nosis. A brief review here highlights the dif-
ferences and similarities among all members
of the subgroup (Tables 2, 3). All subgroup
taxa are moderately large skinks. Emoia tuita-
rere is the smallest with a SVL range of 68 93
mm and E. sanfordi the largest (92 115 mm);
the other three species are predominantly
88 100 mm SVL. All share similar body pro-
All also share similar scalation, although in
some scalation traits means and ranges are
strikingly different. In this respect, E. sanfordi
is the most divergent. It has the lowest num-
ber of Dorsal and the highest number of
4FingLm and 4ToeLm. All five taxa have
near identical ranges of Midbody. We note
that our E. trossula sample consists only of
specimens from the type series and is pre-
dominantly a northern Fiji sample. This geo-
graphic restriction is intentional because
K adavu and southern Lau samoensis subgroup
specimens display genetic and morphological
differences from one another and the n orthern
samples, but samples from those areas are
currently inadequate to address these differ-
Coloration differs strikingly among the
subgroup members. Emoia sanfordi is the most
distinct taxon with its bold green body,
unicolor in many instances, and a large black
patch on its head. The other four taxa have a
brown to olive ground color with a pattern of
dark and light spots. Of these, E. trossula and
Figure 3. Dorsolateral views of two Emoia mokolahi from the extremities of the distribution. A, Individual from ‘Eua,
USNM 322229, paratype; B, individual from Vava‘u, USNM 333684, holotype.
234 PACIFIC SCIENCE · April 2012
E. tuitarere have the boldest pattern of dark
spots and blotches usually arranged in trans-
verse series, hence the origin of the name
barred skinks; both also have numerous bright
yellow streaks spread through the dark spots.
Emoia mokolahi and E. samoensis have some of
this dark spotted pattern with lighter streaks,
but their coloration is much less bold than the
former two taxa.
Natural History
Emoia mokolahi is found both on the ground
and in low shrub trees or on the vertical trunks
of larger trees such as coconut palm. The fre-
quency of discovery in these two situations
was nearly equal; hence we label E. mokolahi
semiarboreal. We never found them in for-
ests, rather at the edge of forests, in scrubby
fencerows, and on palms and other isolated
trees within gardens or pastures. This obser-
vation likely derives from their wariness and
ease of hiding in a dense cluster of trees. In
open situations, they move to the opposite
side of tree trunks from the observer and
a lmost always begin an upward climb. Often,
they were heard, then seen on the ground,
presumably foraging; these individuals imme-
diately moved to a tree or dense growth, a
common behavior of semiarboreal skinks.
Recently, Shea and Stone (2009) reported
mating of E. mokolahi in Va‘vau. The observa-
tion occurred in early March on “the deck of
their house,” although the photograph sug-
gests an “arboreal” copulation on the sides of
a wooden louver or awning. The male had
grasped ( biting) the female’s abdomen imme-
diately behind her right forelimb.
Biogeographic Comments
We noted in a recent report (Zug et al. 2011)
that our morphological and molecular data
support the monophyly of the Emoia samoensis
species group and, further, that molecular
data suggest paraphyly of the two subgroups
(Hamilton et al. 2010). Critically, molecular
and morphological diversity is considerably
greater than our current taxonomy indicates.
Until this diversity is better resolved and de-
scribed, biogeographic hypotheses are likely
premature; nevertheless, we offer a few com-
ments on geographic patterns that are begin-
ning to emerge.
First, Emoia trossula has been briefly (mid-
1980s through the first decade of 2000)
c onsidered a widely occurring species in the
South-central Pacific. It is not! Instead, mo-
lecular data (Hamilton et al. 2010) and mor-
phological data (here and Zug et al. 2011)
demonstrate a high level of interisland diver-
sification, which we interpret as allopatric
speciation. Colonization by samoensis group
members (emphasis on the plural because the
molecular data suggest multiple propagules,
likely arriving at different times and via dif-
ferent routes) happened well before human
dispersal into and colonization of the South
Pacific. We consider the recency (4,000 yr
B.P.) of human colonization as insufficient
time for evolutionary divergence and specia-
tion of the E. samoensis group members.
The data currently available (Hamilton
2008, Hamilton et al. 2010) suggest Vanuatu
as the source of the initial samoensis group
propagules. It has the greatest number of
e xtant samoensis group species, many of which
remain undescribed, and some outer-island
species (e.g., E. parkeri ) have their sister-
group species living in Vanuatu.
What lizard species composed the herpe-
tofauna of Tonga before human arrival? What
species became extinct through anthropo-
genic activities? Pregill’s surveys (Pregill and
Dye 1989, Pregill 1993, Pregill and Steadman
2004) of subrecent fossils (middens and caves)
in Ha‘apai and ‘Eua demonstrated the extinc-
tion of a large iguana (Brachylophus gibbonsi )
and a moderately large gecko (Perochirus sp.)
shortly after human colonization of Tonga.
Two extant skinks, Emoia cyanura ( perhaps
also E. impar because it is osteologically indis-
tinguishable from E. cyanura) and Emoia cf.
mokolahi, were found in the prehuman-arrival
strata of the ‘Eua cave deposits. Other lizards
that are endemic to Tonga and /or nearby is-
land groups are also likely inhabitants before
humans arrived: Lepidodactylus euaensis, Emoia
adspersa, E. tongana, and Tachygyia microlepis.
These two sets of data indicate a lizard fauna
Lizards of Tonga · Zug et al. 235
of eight or nine species before humans ar-
Thus, the extinct, subfossil, and endemic
lizards indicate a minimum lizard fauna of one
iguana, two geckos, and five or six skinks
b efore humans arrived. Emoia adspersa and E.
tongana currently are found in the Ha‘apai
group and northward. It is possible that these
two species were not original members of
Tongan herpetofauna, but rather they derive
from Samoa and were accidently transported
to Tonga by Polynesians or even later by Eu-
ropean and American traders or whalers. The
Pacific parthenogenetic species (Hemidactylus
garnotii, Hemiphyllodactylus typus, Lepidodacty-
lus lugubris, Nactus pelagicus) likely arose from
human transport of one parental species into
the distribution of another species and their
subsequent hybridization. These parthenoge-
netic species likely arrived subsequently in
Tonga and did not arise there. In the instance
of L. lugubris, there is a possibility of a Ton-
gan bisexual species being displaced by the
parthenogen, as appears to occur elsewhere in
the Pacific (Ineich 1999).
Gehyra insulensis and Hemidactylus garnotii
are likely pre-twentieth century arrivals from
the Pacific Rim islands or Asia. Hemidactylus
frenatus is the most recent arrival, rapidly
spreading through the South-central Pacific
in the 1980s and 1990s. The history of two
widespread lizards, Gehyra oceanica and Emoia
nigra, remains enigmatic. Neither has been
found as prehuman-arrival fossils. Although
G. oceanica displays genetic differences be-
tween populations north of and south of the
equator (Fisher 1997), its subfossil absence
suggests that it arrived with the early human
colonizers and may have aided in the extirpa-
tion of endemic Perochirus. Morphology sug-
gests the presence of two Emoia nigra taxa in
the Pacific, one from Vanuatu eastward into
the Pacific and the other one in the Solomon
Islands. It is possible that the Fijian and other
outer Oceania populations received human
assistance in their eastward dispersal. The
nal widespread lizard, Cryptoblepharus poe-
cilopleurus, is another candidate for human-
assisted dispersal. Morphological evidence
hints that this largely Polynesian-distributed
species has eastern Melanesian affinities. If
this proves correct, that will increase the
l ikelihood of its invasive occurrence in the
southern Pacific. The preceding conjectures
derive from a hypothetical bias that the Ocea-
nia lizard faunas were much less diverse than
today’s faunas, and the historical perspective
that lizard diversity decreases incrementally
from west to east.
The collections management staffs of nu-
merous museums have greatly aided our ex-
amination of members of the Emoia samoensis
species group. We appreciate this assistance
and thank D. Kizirian, R. Pascocello, and D.
Dickey, American Museum of Natural His-
tory (AMNH); B. Gill, Auckland Institute and
Museum (AIM); R. Sadlier, Australian
M useum-Sydney (AMS); C. McCarthy, The
Natural History Museum, London (
C. Kishinami and K. Igeta, Bernice P. Bishop
Museum (
BPBM); J. Vindum, California Acad-
emy of Sciences (CAS); D. Watling, private
collection, Suva (DW ); A. Resetar, Field Mu-
seum of Natural History (FMNH); P. Couper,
Queensland Museum of Natural History
(QM); J. Rosado, Museum of Comparative Zo-
ology, Harvard University (MCZ); B. Holling-
sworth, San Diego Natural History Museum
(SDSNH); and S. Gotte, J. Jacobs, K. Tighe,
and R. Wilson, National Museum of Natu-
ral History, Smithsonian Institution (USNM).
Field research was pursued with the approval
of the Office of Prime Minister and the
M inistry of Lands, Surveys, and Natural Re-
sources, Kingdom of Tonga. We greatly ap-
preciate their assistance and permission to
conduct field research throughout the King-
dom and to export voucher material. Our
r esearch into the biology and evolution of
P acific lizards has received support from nu-
merous sources (see footnote 1). We thank
these organizations and their representatives
for enabling our biodiversity research. We
also thank R. Fisher and P. Zug for help with
information and for their editorial recom-
mendations, and M. D. Griffin for the illus-
tration of the paratype. We greatly appreciate
the assistance of A. L. Kaeppler in naming
this species.
236 PACIFIC SCIENCE · April 2012
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Lizards of Tonga · Zug et al. 237
Specimens Examined
Emoia mokolahi Tonga: AMNH 40567 – 40568; AMS
96577 – 96579, 96584; CAS 158241 158242, 158245,
159407 – 159408, 159999; FMNH 58144, 191762;
S DSNH 66147, 66186; USNM 259331 259333, 267849,
322228 322230, 333577, 333684, 333763 333764.
Emoia sanfordi Vanuatu: FMNH 13664, 13666, 13668
13670, 13672 13673; USNM 122176, 334035 334046,
334261 – 334265.
Emoia samoensis Samoa: AMNH 27668 – 27672, 27676,
27695, 27702, 27706, 29244 29245, 41738, 41741;
USNM 215295 215301, 215304, 268376 268380,
215244, 215247 215249, 215251.
Emoia trossula from type series Fiji: AMNH 20927,
29010 – 29011, 29017 – 29022, 40196, 40442 – 40443,
40445, 40491, 40503, 40506, 40539; BMNH,,,, 1938.8.2.9; BPBM
1504; CAS 155958, 155960 – 155962, 156128 – 156130;
DW F524 – 525, F541 – 542; FMNH 13644 – 13645; MCZ
R16941 – 16942, R16945, R16965; USNM 230201.
Emoia tuitarere Cook Islands: AIM LH1896; CAS
183322 – 183325; QM J42397, J45620, 45622 45623;
SDSNH 66114 – 66117, 66145 – 66146; USNM 249663
249666, 252391, 533712, 539181 539190.
... nov.; A. michaelguiheneufi sp. nov.; A. mokolahi (Zug, Ineich, Pregill and Hamilton, 2012); A. nigromarginata (Roux, 1913); A. oriva Zug, (2012); A. parkeri (Brown, Pernetta and Watling, 1980); A. rosssadlieri sp. nov., A. trossula (Brown and Gibbons, 1986); A. tuitarere (Zug, Hamilton and Austin, 2011). ...
Eight new skink genera and 45 newly named species associated with Emoia Gray, 1845 sensu lato that reflects ancient divergence and recent speciation within the assemblage (Reptilia: Squamata). ABSTRACT The lizard genus Emoia Gray, 1845 within the Lygosominae as recognized in 2019 contains about 80 recognized species. Morphological studies have long recognized various species groups (e.g. Brown 1991). More recent molecular studies show ancient divergences. In fact some of these groups are not even closely related to one another, but in fact occur some distance away in the Lygosominae sub familial tree (e.g. Pyron et al. 2013). Based on both morphological and molecular divergence as cited, seven new genera of skinks formerly placed within Emoia as currently recognized are formally named according to the rules of the International Code of Zoological Nomenclature (Ride et al. 1999). Species in the new genera were mainly placed within the so-called E. samoensis group as defined by Brown (1991). The genus Emoa Girard, 1857, type species Emoa nigra, is resurrected for this divergent taxon, also previously placed in the E. samoensis group. The taxon also subdivided into 6 allopatric species. A subgenus for the taxon described as Emoia parkeri Brown, Pernetta and Watling, 1980 is also assigned as well as another subgenus for the species Emoia ponapea Kiester, 1982, the latter being within Emoia sensu stricto. The putative species originally described as Lygosoma stellatus Boulenger, 1900, more recently known as Sphenomorphus stellatus (Boulenger, 1900), is in fact not closely related to other Sphenomorphus Fitzinger, 1843 species at all. Instead the species group is closest to a clade treated as being within Emoia sensu lato, this being the so-called E. samoensis group. However it is divergent enough from that group to be formally placed in a newly named genus, giving a total of eight newly named genera of skinks associated with Emoia sensu lato. Furthermore, 45 obvious but previously unnamed species within relevant genera are also named according to the rules of the International Code of Zoological Nomenclature (Ride et al. 1999) for the first time. There also remains further unrecognized and unnamed species within this assemblage. Keywords: taxonomy; nomenclature; lizards; subfamily; Lygosominae; skinks; genus; Emoia; Sphenomorphus; Emoa; Pacific; Asia; New Guinea; Fiji; Solomon Islands; Indonesia; Papua New Guinea; Malaysia; panopea; nigra; atrocostata; concolor; loyaltiensis; stellatus; new genus; Notanemoia; Cannotbeemoia; Silvaemoia; Griseolaterus; Aintemoia; Caeruleocaudascincus; Ventripallidusscincus; Shireenhoserscincus; new subgenus; Paraemoia; Aquilonariemoia; new species; kimaniadilboden; timdalei; karkarensis; tonylovelinayi; anggigidaensis; stefanbroghammeri; euanedwardsi; paulmulvanyi; martinmulvanyi; paulwoolfi; jamesbondi; richardwarneri; morriedorisioi; minusguttata; dorsalinea; bougainvilliensis; boreotis; aquacauda; yusufmohamudi; davidaltmani; stephengoldsteini; rodneysommerichi; roberteksteini; georgemariolisi; karlagambellae; cathysonnemannae; neilsonnemanni; robvalentici; dannygoodwini; latishadarwinae; stevebennetti; lucybennettae; clivebennetti; craigbennetti; brettbarnetti; williambennetti; kamahlbenneti; drubennetti; jaibennetti; danielbenneti; graysonoconnori; michaelguiheneufi; rosssadlieri; shireenhoserae; daranini. Australasian Journal of Herpetology 40:3-49. Published 10 July 2019. LSID
... Emoia is a genus of 77 species of skinks distributed from western Indonesia (Mentawai Islands) and southeastern Asia to eastern Polynesia (Marquesas, Tuamotus) and Clipperton Island (Brown, 1991;Ineich and Zug, 1991;Zug and Ineich, 1995;How et al., 1998;Zug, 2012;Zug et al., 2011Zug et al., , 2012Shea, 2016). Except for four wide-ranging species (E. ...
I describe a new species of Emoia that is the sixth member in the E. cyanogaster group. It differs from all other Emoia species in its distinctive pattern of serrated black stripes on an emerald-green ground color. Further distinguishing features include its relatively small size, long and narrow snout, large number of toe lamellae, and lack of a distinct interparietal. Specimens of the new species had previously been assigned to E tetrataenia, but the more elongated snout and unique color pattern easily distinguish it from the latter, which is restricted to the D'Entrecasteaux Islands. The new species is known only from Rossel Island in the Louisiade Archipelago, the southeasternmost island of Papua New Guinea, and it is likely endemic to that island. A combination of morphological and distributional evidence suggests that the new species, E. tetrataenia, and E kordoana are probably each other's closest relatives.
... and Grant (1961), Somaweera and Somaweera (2009), Stejneger (1989, 1905, Stoliczka (1870), Stubbs et al. (2017), Supsup et al. (2016), Taylor ( , 1917Taylor ( , 1918Taylor ( , 1919Taylor ( , 1922aTaylor ( , 1922bTaylor ( , 1944, Trautmann (1988), Turner and Green (1996), Volobouev et al. (1993), Wellington (1984, 1985), Werner (1900Werner ( , 1913, Wilson and Swan (2010), Ota (1998, 2005), Yamashiro et al. (2000), Zug (1991Zug ( , 2006, Zug and Kaiser (2014), Zug et al. (2003Zug et al. ( , 2011Zug et al. ( , 2012 and sources cited therein. In terms of the nomenclature adopted within this paper, the following points should also be noted. ...
ABSTRACT There have been numerous studies published on species in the genera Lepidodactylus Fitzinger, 1843, Luperosaurus Gray, 1845, and Pseudogekko Taylor, 1922 with a view to assigning correct genus-level placement. Some authors have split the genera into species groups, while others have reassigned species between genera. More recently in view of newly available molecular data, it has been proposed to merge one or more genera into an expanded genus Gekko Laurenti, 1768. Relying on ancient divergences between species groups ascertained via molecular studies and consistent morphological differences between them, this paper provides a new taxonomy for the relevant genera (excluding Gekko and Ptychozoon Kuhl and Van Hassett, 1822, which are dealt with in separate papers) to better reflect known phylogeny of the relevant species. The result is a division of Lepidodactylus including the groups 1-3 as defined by Brown and Parker (1977) are divided into 9 genera, eight formally named for the first time, as well as two newly named subgenera, Luperosaurus into four genera, two being named for the first time as well as a newly named subgenus and Pseudogekko retained as a single genus, but with a new subgenus formally named to accommodate the most divergent species. Two other subgenera within Lepidodactylus sensu lato are formally named for the first time. Twenty six obviously unnamed species are also formally described for the first time. Keywords: Reptile; Taxonomy; Gecko; Lizard; Asia; Oceana; South-east Asia; Nomenclature; Luperosaurus; Lepidodactylus; Gekko; Pseudogekko; Ptychozoon; new genus; Shireenhosergecko; Jackyhosergecko; Bobbottomcolotes; Martinekcolotes; Adelynhosergecko; Allengreercolotes; Borneocolotes; Rosssadliercolotes; Charlespiersoncolotes; Georgemarioliscolotes; new subgenus; Borealiscolotes; Solomoncolotes; Haroldcoggercolotes; Robwatsoncolotes; new species; shireenhoserae; robjealousi; dalegibbonsi; jarradbinghami; petewhybrowi; jackyhoserae; bobbottomi; potens; crusmaculosus; adelynhoserae; sloppi; huonensis; madangensis; judyfergusonae; haydnmcphiei; matteoae; brettbarnetti; stevebennetti; lucybennettae; lachlanmcpheei; allengreeri; pauldarwini; paulwoolfi; haroldcoggeri; daranini; jenandersonae. Australasian Journal of Herpetology 38:32-64.
... As it happens the trail of published literature alone supports the taxonomy and nomenclature herein and so I cite it all here. The important published material relevant to the taxonomy and nomenclature of Gehyra sensu lato as defined herein and the decisions made herein are as follows: Andersson (1913), Barbour (1912), Bauer (1994), Bauer and Günther (1991), Beckon (1992), Bobrov and Semenov (2008), Boettger (1895), Bonetti (2002), Schüttler (1982, 1983), Boulenger (1883Boulenger ( , 1885aBoulenger ( , 1885bBoulenger ( , 1887, Brongersma (1930Brongersma ( , 1948, Brown (2014), Brown (1955, Brown et al. (2015), Bourke et al. (2017), Buden and Taboroši (2016), Chan-ard et al. (1999Chan-ard et al. ( , 2015, Chrapliwy et al. (1961), Cogger (2014, Cogger et al. (1983), Crombie and Pregill (1999), Daan and Hillenius (1966), Davies (2012), de Rooij (1915, de Vis (1890), Doody et al. (2015), Doughty et al. (2012), Duméril and Bibron (1836), Duméril and Duméril (1851), Ezaz et al. (2009), Fallend (2007), Fisher (1997), Fitzinger (1843, Flecks et al. (2012), Fry (1914, Garman (1901), Gibbons and Clunie (1984), Girard (1858), Glauert (1955), Goldberg (2014), Gray (1834Gray ( , 1842aGray ( , 1842bGray ( , 1845, Grismer et al. (2007), Günther (1877), Hagey et al. (2017), Hall (2002, Hediger (1933), Heinicke et al. (2011), Horner (2005), Hoser (1989, Hutchinson et al. (2014), King (1979King ( , 1982aKing ( , 1982bKing ( , 1984aKing ( , 1984b, King and Horner (1989), Kinghorn (1924), Kluge (1982Kluge ( , 1993, Kopstein (1926), Laube and Langner (2007), Lesson (1830), Loveridge (1934Loveridge ( , 1948, Low (1979), Lucky and Sarnat (2010), Macleay (1877), Manthey and Grossmann (2007), Maryan (2009), McCoy (2015, Mertens (1974), Meyer (1874), Moritz et al. (2017), Oliver et al. (2010, 2012, 2016a, 2016b, 2017, Mitchell (1965), Oudemans (1894), Peters (1874Peters ( , 1875, Peters and Doria (1878), Pianka (1969), Pianka and Pianka (1976), Ride et al. (1999), Rocha et al. (2009), Rösler (2000, 2017, Rösler et al. (2005), Sang et al. (2009), Shea and Sadlier (1999), Sistrom et al. (2009Sistrom et al. ( , 2012Sistrom et al. ( , 2013, Skipwith and Oliver (2014), Strauch (1887), Steindachner (1867), Sternfeld (1925), Storr (1978Storr ( , 1982, Taylor (1962Taylor ( , 1963, Tiedemann et al. (1994), Tonione et al. (2016), Underwood (1954), Wiegmann (1834), Wellington (1984, 1985), Werner (1901), Wilson and Knowles (1988), Wilson and Swan (2017), Yamashiro and Ota (2005), Zug (1991Zug ( , 2013, Zug and Kaiser (2014), Zug et al. (2011Zug et al. ( , 2012 and sources cited therein. In terms of the nomenclature herein, no names should be altered in any way unless absolutely mandatory under the rules of the International Code of Zoological Nomenclature (Ride et al. 1999). ...
ABSTRACT The lizard genus Gehyra Gray, 1834 as currently recognized consists of roughly 50 recognized species found naturally occurring from mainland south-east Asia to Australia and nearby islands to the north and east including the mid Pacific. This number of currently unrecognized species probably exceeds already described species-level taxa, even though this paper formally names 9 new species and 2 new subspecies, all bar one of which have been confirmed by published molecular data. In spite of the ancient heritage of the assemblage, which is unusual in that numerous species occur on both the Asian and Australian continental plates, divergent lineages with antiquity measured potentially in excess of 25 MYA continue to be treated as being within a single genus. To correct the anomaly, this paper recognizes major divergent species groups as self-contained genera using available and newly created genus names in accordance with the International Code of Zoological Nomenclature (Ride et al. 1999). The assemblage of Gehyra as recognized by most authors to date is herein divided into 14 genera, ten of which are formally named for the first time. The species remaining within Gehyra are further divided into two subgenera, one of which is formally named for the first time. The species within Dactyloperus Fitzinger, 1843 are divided into five subgenera, four of which are formally named for the first time. Another of the newly named genera Edaxcolotes gen. nov. is also divided into two subgenera. All newly named genera and subgenera have divergences of more than 10 MYA from all other species based on numerous published phylogenetic studies. Keywords: Taxonomy; Nomenclature; Lizard; Gekkota; Gekkonidae; Gecko; Dtella; Gehyra; Perodactylus; Peropus; Phryia; Phreodora; Dactyloperus; Asia; Australia; New Guinea; Cambodia; Thailand; new genus; Propemaculosacolotes; Crocodilivoltuscolotes; Edaxcolotes; Extensusdigituscolotes; Brevicaudacolotes; Parvomentumparmacolotes; Papuacolotes; Quattuorunguiscolotes; Colotesmaculosadorsum; Thaigehyra; New subgenus; Halmaherasaurus; Purpuracolotes; Maculocolotes; Wedgedigitcolotes; Saxacolinecolotes; Macrocephalacolotes; species; lacerata, membranacruralis; xenopus; serraticauda; brevipalmata; fehlmanni; oceanica; australis; occidentalis; pilbara; new species; hangayi; paulhorneri; bradmaryani; sadlieri; glennsheai; shireenhoserae; marleneswileae; federicorossignolii; grismeri; new subspecies; bulliardi; graemecampbelli.
The purpose of the present application, under Articles 74.1.1 and 81.1 of the Code, is to maintain consistent usage of the commonly used name Emoia nigra (Hombron & Jacquinot, 1853) by setting aside a lectotype designation for Gongylus (Eumeces) freycineti Duméril & Bibron, 1839 by Wells & Wellington in 1985 in favour of a later lectotype designation by Brown in 1991.
Six new genera of skinks associated with Lipinia Gray, 1845 based on morphological and evolutionary divergence as well as twenty seven previously undiagnosed species within the same assemblage. ABSTRACT An ongoing audit of the genus-level classification of the Lygosominae skinks for the genus Lipinia Gray, 1845 and associated species was conducted. It found that the genus-level classification as used in 2019 did not reflect relationships between species or even morphological similarities between groups. As a result of these discrepancies, a new classification framework for the relevant species is given here. This includes reassignment of species between genera, including via resurrection of old and available names as well as the formal erection of six new genera in accordance with the International Code of Zoological Nomenclature (Ride et al. 1999) to accommodate divergent taxa. The new taxonomy and nomenclature is based on peer reviewed scientific evidence. This includes both morphological and molecular evidence as cited and because of this, it is robust and likely to substantively withstand the test of time. The audit also found significant underestimation of the species-level diversity within these genera and twenty seven of these unnamed taxa are formally named for the first time.
Invasive mammals are implicated in the decline or extinction of numerous insular vertebrate species worldwide, yet rediscoveries of supposedly extinct vertebrates occur regularly. In particular, recent records of secretive amphibian and reptile taxa in the Fiji Islands show that earlier claimed extirpations of Fijian wildlife were erroneous. We add to this growing body of evidence by documenting the Fiji barred treeskink Emoia trossula (Squamata: Scincidae) from Vanua Levu island, Fiji, where it was widely considered extirpated. Regional literature, coupled with this new record, emphasizes the conservation importance of remote forest blocks in Fiji as refugia against nonnative predatory mammals. Moreover, a clear need exists for additional survey work in Fiji to document the contemporary distribution of endemic and endangered herpetofaunal species across the archipelago.
The Nactus pelagicus complex consists of a unisexual lineage, N. pelagicus, as well as several genetically distinct bisexual lineages. The unisexual and bisexual lineages are rarely sympatric but do co-occur on two islands in southern Vanuatu. Nactus pelagicus and the bisexual N. multicarinatus co-occur on Aneityum and Tanna Islands, although the distribution of N. multicarinatus may be limited on Aneityum and may be limited to a single locality (Port Resolution) on the eastern coast of Tanna. Previous analyses suggested that these species have different chin scalation patterns. However, species identifications were assigned solely on presence or absence of males from localities. Moreover, because these species occupy different regions, morphological analyses can be confounded by interisland variation. To evaluate whether chin scalation patterns differ consistently between N. pelagicus and N. multicarinatus as previously suggested, we used molecular sequence data to delimit species from nine populations on a single island in Vanuatu. All N. multicarinatus examined had a single chin scalation pattern whereas variation in this trait was observed in N. pelagicus; there was no overlap in this trait between the species. We hypothesize that the variation in this trait in the unisexual species N. pelagicus could result from developmental instability as a result of perturbations during development caused by incompatibility between the two parental genomes that contributed to the formation of this unisexual lineage.
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We use 1344 bp of mitochondrial (ND2) and nuclear (RAG1) DNA sequence data to elucidate the phylogenetic position of the giant New Caledonian scincid lizard Phoboscincus bocourti (Brocchi) which has recently been rediscovered after more than a century. This is one of the largest skinks in the world and one of the only New Caledonian skinks for which molecular data are lacking. The species is a member of the monophyletic Tasmantis clade of Eugongylus group skinks, which is weakly-supported in this study but is consistent with previous molecular studies of this group. The Tasmantis clade includes the endemic skink genera occurring on New Caledonia, New Zealand and Lord Howe Island. Within this radiation P. bocourti receives strong Bayesian support as the sister to its congener, Phoboscincus garnieri (Bavay). We were not able to confirm or refute a possible sister relationship between bocourti and the extinct giant Tongan skink Tachygyia microlepis (Duméril & Bibron) as suggested recently by Ineich on morphological criteria. However, if P. bocourti and T. microlepis are indeed closest relatives our results would imply that Tachygyia is derived from within a New Caledonian clade of skinks.
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The grounds for the synonymization of Gehyra vorax and G. oceanica are critically reassessed on the basis of external morphological measurements made on specimens from throughout the known ranges of these geckos. Ample justification is found for distinguishing the two species. In addition, three morphologically distinct forms are recognized within each species. The closely related Moluccan gecko, G. marginata, is provisionally treated as a fourth form of G. vorax. The distribution of the forms of G. oceanica may provide some evidence of patterns of prehistoric human immigration and commerce in the Pacific, because this species evidently was occasionally transported inadvertently aboard the sailing craft of early Pacific settlers. Gehyra vorax is generally more wary of humans and, therefore, was probably less frequently transported in this manner. Thus, its distribution may reflect more ancient patterns of human traffic. Alternatively it may have colonized Melanesia unassisted by such transport within the last 6-8 million years.
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INEICH I. & ZUG G.R., 1997 - Tachygyia, the giant Tongan skink: extinct or extant ? Cryptozoology, 12 (1993-1996) [1997]: 30-35.
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We examined variation in measurements and scalation of 114 specimens of Murphy's tree skink Emoia murphyi from five island groups of the southwest Pacific. In the largest sample (Niuafo'ou) males were significantly longer than females. Populations from Futuna, Samoa, Niuafo'ou, Vava'u and Ha'apai showed little morphological divergence, and there were no geographic trends in scalation. We conclude that the various populations are conspecific. The lack of morphological discontinuity suggests that the lizards dispersed between the far‐flung island groups recently, and makes more likely the possibility that Polynesian seafaring rather than natural spread was the agent of dispersal. The source population—whether within or beyond the known distribution of E. murphyi—is at present indeterminate.
The Pacific island geckos Gehyra mutilata and Gehyra oceanica were studied on several Pacific Basin archipelagos to determine the degree that their distributions have been modified by humans (as commensals), through the analysis of protein variation using starch gel electrophoresis. Gehyra mutilata is an anthropophilic species that is widespread in the Pacific Basin and Southeast Asia. No protein variation was found in the Pacific Basin and southern Asia, although there were fixed allelic differences between populations of southern Asia and those further north. These results suggest possible recent human-aided transport across the Pacific from a population that experienced a genetic bottleneck in southern Asia. Gehyra oceanica, based on protein variation, consists of two natural groups in the Pacific, a northern (Micronesian) form and a southern (Melanesian and Polynesian) form. The northern form has very similar gene frequencies across its range in Micronesia. The southern form has its greatest allelic diversity in the south-central Pacific. F-statistics for G. oceanica in the south fall within the range of values in the literature for mainland Australian species of Gehyra that are not human commensals and for other island lizards that have been considered as natural dispersers. These values are consistent with the hypothesis that G. oceanica was naturally dispersed across the Pacific, prior to the arrival of humans and that the equatorial currents are a barrier to natural, north-south gene flow/dispersal in Pacific Basin lizards. However, human-aided dispersal within the northern and southern regions cannot be ruled out. By comparing the ecology of these two species, G. oceanica has the adaptations necessary for natural oversea dispersal, whereas G. mutilata has an ecology consistent with human-mediated dispersal, in support of the conclusions from the genetic data.
The diversity and distribution of Pacific island iguanas were altered drastically following human colonization around 2800 years ago. A giant iguana recovered from archaeological sites in the Ha'apai group of islands, Kingdom of Tonga, became extinct within a century of human arrival. We describe this iguana as a new species of Brachylophus, a genus with two small arboreal species found today in Fiji (Brachylophus fasciatus, Brachylophus vitiensis) and parts of Tonga (Brachylophus fasciatus). Additional evidence suggests that B. fasciatus was probably introduced to Tonga (the type locality) by prehistoric people 2000 years after extinction of the giant form. Lapitiguana impensa, described in 2003 from Fiji by G. K. Pregill and T. H. Worthy was an even larger extinct iguana that also succumbed to human impact. The two living species are relicts of a much richer evolutionary history than previously known.