Description of a new species of the genus Cnemaspis Strauch, 1887 (Reptilia: Squamata: Gekkonidae) from the Nilgala Savannah forest, Uva Province of Sri Lanka
Author
Karunarathna, Suranjan
Author
Bauer, Aaron M.
Author
Silva, Anslem De
Author
Surasinghe, Thilina
Author
Somaratna, Lankani
Author
Madawala, Majintha
Author
Gabadage, Dinesh
Author
Botejue, Madhava
Author
Henkanaththegedara, Sujan
Author
Ukuwela, Kanishka D. B.
text
Zootaxa
2019
2019-01-18
4545
3
389
407
journal article
27628
10.11646/zootaxa.4545.3.4
92bd3b92-5be7-419b-ad51-301d63c4b0f1
1175-5326
2618952
D7F2BB9B-B6D6-40F0-82DF-733C6E65520E
Cnemaspis nilgala
sp. nov.
(
Figures 2–3
;
Tables 1–4
)
Holotype
.
2018.07.01.NH,
Adult
male,
32.9 mm
SVL
(
Figure 2
), collected from rock cave in
Serawa
,
Bibila
,
Monaragala District
,
Uva Province
,
Sri Lanka
(
7.264075 N
,
81.356997 E
,
elevation
260 m
a.s.l.
WGS1984+-) collected on
6 November 2002
by
Aaron M. Bauer
&
Anslem de Silva.
Paratypes
.
NMSL
2018.06.01.NH, Adult female,
31.5 mm
SVL
, collected from rockcave in
Pitakumbura
,
Bibila
,
Monaragala District
,
Uva Province
,
Sri Lanka
(
7.264069 N
,
81.359025 E
,
elevation
275 m
a.s.l.
WGS1984+-), collected on
6 November 2002
by
Aaron M. Bauer
& Anslem
de Silva
; 2018.06.02.NH,
Adult
male,
31.1 mm
SVL
(
Figure 3
) and 2018.06.03.NH,
Adult
male,
31.7 mm
SVL
, collected from rockcave in
Yakunhela
,
Bibila
,
Monaragala District
,
Uva Province
,
Sri Lanka
(
7.200950 N
,
81.329731 E
,
elevation
282 m
a.s.l.
), collected on
25 June 2018
by
Suranjan Karunarathna
.
Diagnosis.
Cnemaspis nilgala
sp. nov.
, can be readily distinguished from its peninsular Indian and Sri Lankan congeners by a combination of the following morphological and meristic characteristics and color pattern: maximum SVL
32.9 mm
; dorsum with homogeneous, unkeeled granular scales; internasal present; ventral scales smooth, venter subimbricate; two enlarged postmentals including median chin scale; each postmental bounded by 6–7 posterior postmental scales including medial chin scale; chin, throat, gular, pectoral and abdominal scales smooth; 17–19 ventral scales across midbody; 4 very weakly developed tubercles on posterior flank; 179–187 paravertebral granules linearly arranged; precloacal pores absent in males, 7–9 femoral pores on each side separated by 14–15 unporedfemoro-precloacal scales, 5–6 enlarged femoral scales; 122–129 ventral scales; subcaudals smooth, median row enlarged, in an irregular series of subhexagonal scales, subequal in width; 7–8 supralabials; 6–7infralabials; 17–18 subdigital lamellae on fourth digit of pes.
FIGURE 2.
Close-ups of
Cnemaspis nilgala
sp. nov.
male holotype (2018.07.01.NH): (
a
) dorsal head, (
b
) lateral head, (
c
) ventral head, (
d
) cloacal characters and femoral pores,(
e
) subdigital lamellae on manus, (
f
) subdigital lamellae on pes, (
g
) smooth ventral scales, (
h
) dorsal granules of the body, (
i
) dorsal and ventral aspects of male holotype (2018.07.01.NH), (
j
) dorsal and ventral aspects of female paratype (2018.06.01.NH) (Photos: Madhava Botejue).
The new species most closely resembles Sri Lankan congeners in the
C. podihuna
clade (
Agarwal
et al
., 2017
):
C. alwisi
,
C. gemunu
Bauer, de Silva, Greenbaum & Jackman
,
C. kandambyi
Batuwita & Udugampala
,
C. molligodai
Wickramasinghe & Munindradasa
,
C. phillipsi
Manamendra-Arachchi, Batuwita & Pethiyagoda
,
C. podihuna
,
C. punctata
Manamendra-Arachchi, Batuwita & Pethiyagoda
,
C. rajakarunai
,
C. rammalensis
Vidanapathirana, Rajeev, Wickramasinghe, Fernando & Wickramasinghe
, and
C. scalpensis
Ferguson
(systematic position confirmed based on presence of enlarged subcaudals, and hexagonal or subhexagonal-shaped scales on the tail). Of these similar species, the new species differs from
C. kandambyi
,
C. molligodai
and
C. podihuna
from the absence (
versus
presence) of precloacal pores. It can be diagnosed from
C. alwisi
,
C. punctata
and
C. rajakarunai
,
respectively, by the presence of 122–129 (
versus
146–152, 131–135 and146–186) ventral scales, by having fewer unpored femoro-precloacal scales ranging from 14–15 (
versus
18–19, 24–26 and 20–22), by the presence of 7–8 (
versus
8–10
,
7–10 and 9–11
) supralabials, body relatively short, relatively smaller SVL of
31.5–32.9 mm
(
versus
37.8–39.9 mm
, 35.2–37.1 and 36.2–40.1) (
Table 3
). The new species also differs from
C. gemunu
,
C. phillipsi
,
C. rammalensis
and
C. scalpensis
, respectively, by the presence of fewer femoral pores ranging from 7–9 (
versus
11– 14, 15–16, 15 and 13–15). The new species further differs from
C. phillipsi
,
C. rammalensis
and
C. scalpensis
, respectively, by the presence of 17–19 (
versus
21–25, 28 and 21–23) fewer belly scales across the ventral at midbody and from
C. gemunu
by the presence of 17–19 (
versus
13–16) more ventral scales across the mid body.
The new species further differs from the following species in having unkeeled gular, pectoral, and abdominal scales (
versus
keeled):
Cnemaspis amith
Manamendra-Arachchi, Batuwita & Pethiyagoda
,
Cnemaspis clivicola
Manamendra-Arachchi, Batuwita & Pethiyagoda
,
Cnemaspis kallima
Manamendra-Arachchi, Batuwita & Pethiyagoda
,
Cnemaspis kandiana
(Kelaart)
,
Cnemaspis kumarasinghei
Wickramasinghe & Munindradasa
,
Cnemaspis latha
Manamendra-Arachchi, Batuwita & Pethiyagoda
,
Cnemaspis menikay
Manamendra-Arachchi, Batuwita & Pethiyagoda
,
Cnemaspis pava
Manamendra-Arachchi, Batuwita & Pethiyagoda
,
Cnemaspis pulchra
Manamendra-Arachchi, Batuwita & Pethiyagoda
,
Cnemaspis retigalensis
Wickramasinghe & Munindradasa
,
Cnemaspis samanalensis
Wickramasinghe & Munindradasa
,
Cnemaspis silvula
Manamendra-Arachchi, Batuwita & Pethiyagoda
,
Cnemaspis tropidogaster
(Boulenger)
, and
Cnemaspis upendrai
Manamendra-Arachchi, Batuwita & Pethiyagoda. The
new species
further differs from
C. clivicola
,
C
.
kallima
,
C
.
kandiana
,
C
.
menikay
,
C
.
pava
,
C
.
pulchra
,
C
.
retigalensis
,
C
.
samanalensis
,
C
.
silvula
,
C
.
tropidogaster
, and
C
.
upendrai
by having homogeneous dorsal scales (versus heterogeneous). The new species can be separated from
Cnemaspis amith
,
C
.
kumarasinghei
, and
C
.
latha
, by absence of (versus 3–5) precloacal pores.
TABLE 1.
A comparison of average morphometric ratios (adjusted for snout length) between
Cnemaspis nilgala
sp. nov.
(
n
=6),
C. alwisi
(
n
=8),
C. rajakarunai
(
n
=8) and
C. punctata
(
n
=8). All 17 morphometric ratios showed significant differences between species (
p
<0.05).
Morphometric |
Average ± S.E. |
Chi-square |
p
- value
|
parameter |
C. nilgala
|
C. alwisi
|
C. rajakarunai
|
C. punctata
|
value (
d.f
=3)
|
ED |
0.518 (±0.004) |
0.435 (±0.004) |
0.369 (±0.016) |
0.345 (±0.004) |
23.295 |
0.0000 |
EN |
0.863 (±0.003) |
0.807 (±0.006) |
0.882 (±0.009) |
0.760 (±0.009) |
21.600 |
0.0001 |
SN |
0.253 (±0.004) |
0.165 (±0.004) |
0.173 (±0.003) |
0.173 (±0.005) |
16.102 |
0.0011 |
EL |
0.172 (±0.003) |
0.200 (±0.006) |
0.167 (±0.004) |
0.217 (±0.004) |
20.640 |
0.0001 |
IO |
0.271 (±0.004) |
1.153 (±0.008) |
1.166 (±0.010) |
0.662 (±0.011) |
23.938 |
0.0000 |
HL |
2.521 (±0.006) |
2.235 (±0.011) |
2.295 (±0.023) |
2.278 (±0.012) |
16.973 |
0.0007 |
HW |
1.444 (±0.005) |
1.390 (±0.004) |
1.390 (±0.017) |
1.382 (±0.008) |
12.432 |
0.0060 |
HD |
0.740 (±0.006) |
0.845 (±0.009) |
0.757 (±0.011) |
0.798 (±0.010) |
20.402 |
0.0001 |
JL |
1.531 (±0.005) |
1.437 (±0.015) |
1.399 (±0.012) |
1.407 (±0.013) |
15.807 |
0.0012 |
IN |
0.290 (±0.004) |
0.268 (±0.006) |
0.284 (±0.008) |
0.313 (±0.010) |
11.934 |
0.0076 |
SED |
2.298 (±0.006) |
2.065 (±0.044) |
2.118 (±0.013) |
1.983 (±0.006) |
18.559 |
0.0003 |
LAL |
1.482 (±0.006) |
1.390 (±0.005) |
1.235 (±0.008) |
1.243 (±0.008) |
24.462 |
0.0000 |
SVL |
8.793 (±0.032) |
8.008 (±0.038) |
8.313 (±0.031) |
9.065 (±0.015) |
27.154 |
0.0000 |
TRL |
4.153 (±0.004) |
3.448 (±0.029) |
3.884 (±0.046) |
3.413 (±0.024) |
24.008 |
0.0000 |
TBL |
1.750 (±0.005) |
1.672 (±0.008) |
1.467 (±0.018) |
1.457 (±0.013) |
23.942 |
0.0000 |
TAL |
7.732 (±0.026) |
9.093 (±0.093) |
9.935 (±0.026) |
9.785 (±0.132) |
21.717 |
0.0001 |
TBW |
0.930 (±0.006) |
0.888 (±0.016) |
0.966 (±0.028) |
1.015 (±0.009) |
12.5580 |
0.0057 |
TABLE 2.
Uncorrected pairwise genetic distances of the ND2 gene between
Cnemaspis nilgala
sp. nov.
and other species of the
Cnemaspis podihuna
clade in Sri Lanka.
Species |
gemunu
|
alwisi
|
cf. gemunu
|
cf. podihuna
|
phillipsi
|
podihuna
|
punctata
|
scalpensis
|
nilgala
sp. nov.
|
sp. 0 9 |
sp. 10 |
C.
|
C.
|
C.
|
C.
|
C.
|
C.
|
C.
|
C.
|
C.
|
C.
|
C.
|
C. gemunu
|
-
|
C. alwisi
|
19.3 |
- |
C. cf. gemunu
|
7.1 |
18.2 |
- |
C. cf. podihuna
|
20.4 |
17.6 |
19.1 |
- |
C. phillipsi
|
11.1 |
18.7 |
10.0 |
19.4 |
- |
C. podihuna
|
20.6 |
17.8 |
19.0 |
7.30 |
19.2 |
- |
C. punctata
|
21.5 |
13.9 |
19.8 |
18.5 |
19.8 |
18.9 |
- |
C. scalpensis
|
11.1 |
18.5 |
10.7 |
19.6 |
5.0 |
19.4 |
20.1 |
- |
C. nilgala
sp. nov.
|
20.5 |
13.5 |
18.5 |
17.6 |
18.7 |
17.6 |
13.9 |
18.2 |
- |
C.
sp. 0 9
|
20.0 |
13.1 |
19.0 |
16.6 |
18.9 |
16.9 |
14.1 |
18.3 |
7.8 |
- |
C.
sp. 10
|
19.8 |
12.9 |
17.6 |
17.2 |
19.7 |
17.5 |
15.0 |
18.8 |
13.1 |
12.9 |
- |
C.
sp. 11
|
22.3 |
19.5 |
19.8 |
19.8 |
22.2 |
20.2 |
21.9 |
22.3 |
21.7 |
20.5 |
20.5 |
Description of
Holotype
.
An adult male,
32.9 mm
SVL. Head relatively short (HL 28.2% of SVL, HL 60.6% of TRL), narrow (HW 16.0% of SVL, HW 56.8% of HL), depressed (HD 8.5% of SVL, HD 30.0% of HL) and distinct from neck (
Table 3
). Snout relatively long (ES 70.1% of HW, ES 39.8% of HL), less than twice the length of eye diameter (ED 53.5% of ES), more than half length of jaw (ES 66.1% JL), snout slightly concave in lateral view; eye relatively small (ED 21.3% HL), larger than the ear (EL 33.8% ED), pupil rounded; orbit length equals to eye-to-ear distance (OD 100.1% EE) and to the length of IV digit in manus (OD 99.2% DLM IV); supraocular ridges are not prominent or absent; ear opening very small (EL 7.2% HL), deep, taller than wide, larger than nostrils, smaller than eyes; two rows of scales separates orbit from supralabials; interorbital gap is narrow (IO 11.1% of SN), subequal to snout to nostril length (IO 107.3% of HL); eye to nostril distance greater than the eye to ear distance (EN 81.3% of EE); granules on snout very smooth, larger than those on interorbital and occipital regions; canthus rostralis nearly absent, 12, smoothly round scales from eye to nostril; scales of the interorbital region ovular and smooth; tubercles absent both on the sides of the neck and around the ear (
Tables 4
). Unkeeled, rounded, juxtaposed scales present on the chin and throat raised, smooth, small; unkeeled, imbricate scales on the gular and pectoral regions, and the abdomen. Rostral scale wider than long, 4/5 partially divided by a medial groove, in contact with first supralabial. Nostrils separated by two enlarged supranasals with a single internasal (
Figure 2
); no enlarged scales behind the supranasals. Nostrils oval, dorsolaterally orientated; nostrils not in contact with first supralabial. Two postnasals smooth, larger than nostrils, the lower one partially in contact with first supralabial. Mental sub-rhomboid in shape, as wide as long, posteriorly in contact with two enlarged postmentals (smaller than mental, and lager than chin scale); postmentals in contact medially and bordered posteriorly with seven unkeeled posterior-postmental scales (smaller than postmentals), in contact with the 1
st
and 2
nd
infralabials; ventral scales smaller than posterior-postmentals. Supralabials 7/7, infralabials 7/7, becoming smaller towards the gape (
Figure 3
). Ear opening oval vertically, backward slanted (EL,
0.67 mm
), 19 scales between anterior margin of the ear opening and the posterior margin of the eye. Body slender, relatively short (AG 46.6% of SVL). Middorsal granules homogeneous, 179 paravertebral granules; 122 midventral scales, smooth; 78 midbody scales; four very weakly developed tubercles on the flanks; ventro-lateral scales enlarged; pectoral and abdominal scales smooth, subimbricate to imbricate towards precloacal region, abdominal scales slightly larger than dorsals; 17 belly scales across ventral; smooth scales around vent and base of tail, subimbricate; no pore-bearing precloacal scales or precloacal depressions; 8 and 7 femoral pores on left and right sides, respectively; 14 unpored femoroprecloacal scales in between pores in each side; 5 enlarged femoral scales (
Figure 2
).
FIGURE 3.
Cnemaspis nilgala
sp. nov.
male paratype (2018.06.02.NH) live in-situ (
a
) dorsolateral view of the full body; (
b
) dorsal view of the full body; (
d
) cloacal characters, femoral pores, and subcaudals pattern; (
d
) dorsal head; (
e
) lateral head; (
f
) ventral head; (
g
) smooth ventral area of the body; (
h
) subdigital lamellae on pes (Photos: Madhava Botejue).
Forelimbs moderately long, slender (LAL 16.4% of SVL, UAL 13.7% of SVL); hind limbs long, tibia relatively shorter than the femur (TBL 19.5% of SVL, FEL 21.7% of SVL). Dorsal, anterior, ventral and posterior surfaces of upper arm with unkeeled and less imbricate scales, scales of the anterior surface twice larger than those of the other parts; ventral scales unkeeled. Scales on dorsal, ventral and tail less imbricate. Dorsal and anterior surfaces of lower arm with unkeeled and less imbricate scales, ventral and posterior surfaces with keeled scales those are less imbricate. Scales on dorsal surface of the thigh less keeled and granular, imbricate scales on the anterior, posterior and ventral surfaces, scales on the anterior and ventral surfaces are twice the size than those of the other parts. Dorsal, anterior, ventral and posterior surfaces of tibia with unkeeled and less imbricate scales, scales of the ventral surface twice larger than those of the other parts, dorsal and posterior surfaces with unkeeled homogeneous granules.
Dorsal and ventral scales on the manus and the pes with unkeeled granules. Dorsal surface of digits with granular scales. Digits elongate and slender with an inflected joint, all bearing slightly recurved claws. Subdigital lamellae entire (except the divided lamellae at first interphalangial joint), unnotched; subdigital lamellae on manus: digit I, 11, digit II, 13, digit III, 15, digit IV, 17, digit V, 15; subdigital lamellae on pes: digit I, 11, digit II, 13, digit III, 15, digit IV, 17, digit V, 13; interdigital webbing absent; relative length of digits of manus: IV (
2.6 mm
)>V (
2.1 mm
)> III (2.0 mm)> II (
1.8 mm
)> I (
1.5 mm
); relative length of digits of pes IV (
3.3 mm
)> V (
2.9 mm
)> III (
2.7 mm
)> II (
2.3 mm
)> I (
1.3 mm
). Regenerated tail of
holotype
shorter than the snout-vent length (86.3% of SVL); tail base greatly swollen (TBW 3.4), homogeneous scales on the dorsal aspect of the tail directed backwards, no spine-like tubercles at the base of tail; tail with 4–5 enlarged flattened obtuse scales forming whorls; a small postcloacal spur on each side, dorso-ventrally flattened and narrow (
Figure 3
); subcaudals smooth and are arranged into an irregular subhexagonal median series.
TABLE 3.
Morphometric data for the holotype and three paratypes of
Cnemaspis nilgala
sp. nov.
from Nilgala savannah
forest,
Sri Lanka
.
Measurements |
Holotype (Male) 2018.07.01.NH |
Paratype (Female) 2018.06.01.NH |
Paratype (Female) 2018.06.02.NH |
Paratype (Male) 2018.06.03.NH |
ED |
2.0 |
1.8 |
2.0 |
2.0 |
OD |
2.6 |
2.3 |
2.7 |
2.5 |
EN |
3.2 |
3.1 |
3.2 |
3.3 |
ES |
3.7 |
3.6 |
4.0 |
4.2 |
SN |
1.0 |
0.9 |
1.0 |
1.0 |
NW |
0.1 |
0.1 |
0.1 |
0.1 |
EE |
2.6 |
2.6 |
2.7 |
2.7 |
SA |
16.1 |
14.8 |
16.7 |
16.7 |
EL |
0.7 |
0.7 |
0.7 |
0.7 |
IO |
1.0 |
1.0 |
1.1 |
1.2 |
HL |
9.3 |
9.2 |
9.0 |
9.4 |
HW |
5.3 |
5.2 |
5.5 |
5.5 |
HD |
2.8 |
2.7 |
3.4 |
3.5 |
JL |
5.6 |
5.6 |
6.1 |
6.3 |
IN |
1.0 |
1.1 |
1.1 |
1.0 |
SED |
8.5 |
8.4 |
8.6 |
8.5 |
UAL |
4.5 |
4.5 |
4.8 |
4.8 |
LAL |
5.4 |
5.4 |
4.9 |
5.2 |
PAL |
4.3 |
4.3 |
4.4 |
4.4 |
DLM (i) |
1.5 |
1.5 |
1.5 |
1.5 |
DLM (ii) |
1.8 |
1.8 |
1.9 |
1.9 |
DLM (iii) |
2.0 |
2.0 |
2.0 |
2.0 |
DLM (iv) |
2.6 |
2.6 |
2.6 |
2.7 |
DLM (v) |
2.1 |
2.0 |
2.1 |
2.1 |
SVL |
32.9 |
31.5 |
31.1 |
31.7 |
TRL |
15.3 |
15.1 |
15.3 |
15.4 |
TW |
5.8 |
5.7 |
5.8 |
5.8 |
TD |
3.9 |
3.9 |
3.8 |
3.9 |
FEL |
7.1 |
7.1 |
7.3 |
7.3 |
TBL |
6.4 |
6.4 |
6.3 |
6.3 |
HEL |
6.3 |
6.3 |
6.4 |
6.4 |
DLP (i) |
1.3 |
1.2 |
1.3 |
1.3 |
DLP (ii) |
2.3 |
2.3 |
2.3 |
2.3 |
DLP (iii) |
2.7 |
2.7 |
2.7 |
2.7 |
DLP (iv) |
3.3 |
3.3 |
3.3 |
3.3 |
DLP (v) |
2.9 |
2.8 |
2.9 |
2.9 |
TAL |
28.4 (Rg) |
28.4 (Rg) |
Broken |
Broken |
TBW |
3.4 |
3.4 |
3.4 |
3.4 |
Color in life.
The color of the head, body and limbs on the dorsal side generally vary from light grey to brown with small black and white spots on the entire dorsum, paired black paravertebral blotches can be seen; an oblique black line is present in between the eye and the nostrils on either side, and dirty white lines are present in the occipital area; there is a narrow ‘V’ shaped, pale grey patch on the occipital area with scattered cream white spots. Two distinct black spots on the dorsolateral surfaces of the shoulders; tail is dirty golden-brown on the dorsum, 7– 9 faded cream white cross-bands present along the tail; three straight, dark brown postorbital stripes extend from eyes downward and backwards (
Figure 3
); the pupil is circular and black with the surrounding scales being yellowish brown in color; supralabials are cream white and spotted, and infralabaials are bright yellow with dusted with black; chin, throat, gular and lower shoulder scales are bright orange-yellow without dark spots; pectoral, abdomen and cloacal scales cream white without dark spots; post-cloacal spur and subcaudal scales pale orangeyellow; limbs have white patches; manus and pes with black and white stripe arrangement.
Color of preserved specimens.
Dorsally dark brown with pale colored, dark paravertebral blotches distinct; Ventral surface cream colored with some scales on thigh, tail base and arms with dark brown margins. Color patterns in preservative not similar to that in life, all the dark marking fades, with the dorsal background color becoming slightly darker; chin, throat, gular and lower shoulder scales are cream color without dark spots (
Figure 2
).
TABLE 4.
Meristic data of holotype and three paratypes of
Cnemaspis nilgala
sp. nov.
from Nilgala savannah forest, Sri
Lanka.
Characters |
Holotype (Male) 2018.07.01.NH |
Paratype (Female) 2018.06.01.NH |
Paratype (Male) 2018.06.02.NH |
Paratype (Male) 2018.06.03.NH |
Flank spines |
4 |
4 |
4 |
4 |
SUP (L, R) |
7/7 |
7/7 |
8/8 |
7/7 |
INF (L, R) |
7/7 |
7/7 |
6/6 |
7/7 |
INTS |
31 |
29 |
29 |
30 |
PM |
3 |
3 |
3 |
3 |
PP |
7 |
7 |
7 |
6 |
SUN (L, R) |
2 |
2 |
2 |
2 |
PON (L, R) |
1 |
1 |
1 |
1 |
INT |
1 |
1 |
1 |
1 |
SUS |
17 |
13 |
16 |
15 |
BET (L, R) |
19 |
21 |
19 |
17 |
CAS (L, R) |
12/12 |
11/12 |
11/11 |
10/11 |
SLM (i) (L, R) |
11/11 |
11/11 |
12/11 |
11/11 |
SLM (ii) (L, R) |
13/13 |
13/13 |
14/14 |
14/14 |
SLM (iii) (L, R) |
15/15 |
15/15 |
16/15 |
15/15 |
SLM (iv) (L, R) |
17/17 |
17/17 |
17/17 |
17/17 |
SLM (v) (L, R) |
15/15 |
15/15 |
15/15 |
15/15 |
PG |
179 |
184 |
187 |
181 |
MBS |
78 |
76 |
71 |
75 |
MVS |
122 |
125 |
129 |
127 |
BLS |
17 |
19 |
19 |
19 |
SLP (i) (L, R) |
11/11 |
11/11 |
11/12 |
11/11 |
SLP (ii) (L, R) |
13/13 |
15/15 |
14/14 |
15/15 |
SLP (iii) (L, R) |
15/15 |
15/15 |
15/15 |
15/15 |
SLP (iv) (L, R) |
17/17 |
17/17 |
18/18 |
17/17 |
SLP (v) (L, R) |
13/ 13 |
13/ 13 |
13/ 13 |
13/ 14 |
PCP |
0 |
0 |
0 |
0 |
FP (L, R) |
7/8 |
0 |
8/8 |
8/9 |
FS |
5 |
– |
6 |
5 |
UP |
14 |
– |
15 |
15 |
FIGURE 4.
Distribution of
Cnemaspis nilgala
sp. nov.
in Nilgala savannah forest, Monaragala District, Sri Lanka. Holotype locality is indicates solid triangle, Paratype localities are marked with solid squares, and additional localities are with solid circles.
Variation.
The SVL of adult specimens in the
type
series (
n
=4) size ranges from
31.5 to 32.9 mm
; number of supralabials 7–8, and number of infralabials 6–7; number of interorbital scales 29–31; number of supraciliaries above the eye is between 13–17; number of canthul scales 10–12; number of scales from eye to tympanum 17–21; number of lamellae on digit I of the manus is between 11–12, number of lamellae on digit II of manus is between 13–14; number of lamellae on digit III of manus is between
1 5–16
; number of ventral scales 122–129; number of belly scales across ventral 17–19; number of midbody scales 71–78; number of lamellae on digit I of pes is between 11–12; number of lamellae on digit II of pes is between 13–15; number of lamellae on digit IV of pes is between 17–18; number of lamellae on digit V of pes is between 13–14, and number of paravertebral granules 179– 187 (
Table 3–4
).
Etymology.
The species name is an eponym (
nilgala
) for the region it inhabits, the Nilgala savannah forest in
Sri Lanka
(7.133333–
7.233333 N
and 81.266667–
81.335400 E
), formed here as a noun in apposition.
Suggested vernacular names.
The vernacular names suggested for the species are: Nilgala diva-sari huna (in Sinhala), Nilgala pahal-palli (in Tamil), Nilgala day gecko (in English).
Remarks.
The records of
Cnemaspis alwisi
from Nilgala forest and vicinity (7.133333–
7.233333 N
and 81.266667–
81.335400 E
) by
Karunarathna & Amarasinghe (2011)
refer to
Cnemaspis nilgala
sp. nov.
Distribution and habitat.
The Nilgala savannah forest (NSF) is a savannah dominated forest approximately 12,432 ha in size, situated in the lower plains of the
Uva Province
, Monaragala District (intermediate bioclimatic zone) in the eastern part of
Sri Lanka
(
Figure 4
). The NSF approximately lies between 7.133333–
7.233333 N
and 81.266667–
81.335400 E
. Different parts of the NSF are under the protection of both the Department of Wildlife Conservation and Forest Department, although the statutory protection status remains uncertain (
Goonewardene
et al.
2003
;
Karunarathna
et al
. 2013
;
Kumara
et al
. 2017
). The mean annual rainfall varies between
1500 and
2000
mm, received mainly during the north-east monsoon (October– January) (de
Silva
et al
. 2004
). The mean annual temperature of the area is 28–31°C, and its elevation range is
220–
570 m
. The major vegetation of NSF can be classified as dry monsoon grassland (savannah), although the area around Nilgala is mostly lowland tropical dry mixed evergreen forests (
Gunatileke & Gunatileke 1990
). Furthermore, four other secondary vegetation categories were identified within NSF: savannah grasslands, deciduous seasonal forests (
Figure 5
), anthropogenically modified vegetation (e.g. croplands and home gardens) and degraded lands predominantly covered by thorny weeds (
Karunarathna & Amarasinghe 2011
). So far, this species is only recorded from rock outcrops with prehistoric granite caves of the
type
similar to those that have been subjected been subjected to historical (since stone-age until the colonial period) human occupancy (
Goonewardene
et al
. 2003
). It is likely that this species occurs throughout the NSF and nearby habitats, but aggregated in these relatively undisturbed granite caves.
Autecology.
Cnemaspis nilgala
sp. nov.
was scarce in and around NSF. Our survey revealed only 3 (±1) geckos per man-hour (approximately a total surveyed area of
25 km
2
). This species was restricted to rock outcrops (2 locations, 7 individuals) and granite caves embedded in forested areas, and ascended up to
4 m
along vertical surfaces (4 locations, 21 individuals) (
Figure 5
). These habitats were relatively moist and cool in comparison to the cave exterior where temperature of the rock surface of the cave interior varied between 27.5–28.2 ˚C. Inside the caves, the light intensity and the humidity were 0–582 Lux and 82–96%, respectively. The geckos were active during the day time (0700–1700 h) and, when disturbed, sought refuge in the crevices of the rocky outcrops. The new species was sympatric (at both local habitat and the microsite) with several other micro-endemic cavedwelling geckos (
Calodactylodes illingworthorum
Deraniyagala
,
Cnemaspis
sp.,
Cyrtodactylus
sp.,
Hemidactylus depressus
Gray
,
H. frenatus
Duméril and Bibron
,
H. hunae
Deraniyagala
,
H. triedrus
(Daudin)
,
H. parvimaculatus
Deraniyagala
). During the survey, across six distinct locations (
Figure 4
), we documented
14 females
, nine males, five juveniles, and 63 unhatched eggs (likely belong to the new species given their proximity to the habitats of adults) deposited in six different communal egg laying sites within an extent of ca.
40km
2
area. From July to September (2016), hatchlings, juveniles and gravid females carrying one or two eggs were observed. Older and newly laid eggs were observed on granite rock crevices, typically laid in pairs. The eggs were pure white in color almost spherical in shape (mean diameter 5.16 ±
0.02 mm
(
n
=26)), with a slightly flattened side attached to the rocky substrate.
Conservation status.
Application of the IUCN Red List criteria indicates that
C. nilgala
sp. nov.
is Critically Endangered due to having an area of occupancy (AOO) <
10km
2
(six locations,
4.7 km
2
in
total assuming a
500 m
radius around the georeferenced location) and an extent of occurrence (EOO) <
100 km
2
(
32.43 km
2
) in the lower elevations of
Uva Province
[applicable criterion is B2-b (iii)]. Further, the characteristic habitats of this species, monsoon-influenced savannah grasslands embedded with rock outcrops and granite rock caves, are not spatially extensive in the intermediate zone of
Sri Lanka
, which suggests that the habitat area suitable for this species is small. See the map (
Figure 4
) for distribution data of
C. nilgala
sp. nov.