Discovery of a new species of Euphlyctis (Anura: Dicroglossidae) from the western coastal plains of peninsular India
Author
Dinesh, K. P.
Zoological Survey of India (ZSI), Western Regional Centre (WRC), Pune- 411044, India
Author
Channakeshavamurthy, B. H.
Zoological Survey of India (ZSI), Western Ghats Regional Centre (WGRC), Calicut- 673006, India
Author
Deepak, P.
0000-0003-2261-4671
Mount Carmel College, Autonomous; No. 58, Palace Road, Vasanth Nagar, Bengaluru- 560052, India deepak. sphaeros @ gmail. com; https: // orcid. org / 0000 - 0003 - 2261 - 4671
deepak.sphaeros@gmail.com
Author
Shabnam, A.
Zoological Survey of India (ZSI), Western Regional Centre (WRC), Pune- 411044, India & Zoological Survey of India (ZSI), Western Regional Centre (WRC), Pune- 411044, India
Author
Ghosh, Avrajjal
0000-0002-1049-6455
School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar- 752050, India avrajjal. ghosh @ niser. ac. in; https: // orcid. org / 0000 - 0002 - 1049 - 6455
avrajjal.ghosh@niser.ac.in
Author
Deuti, Kaushik
Herpetology Division, FPS Building, Zoological Survey of India (ZSI), 27 JL Nehru Road, Kolkata- 700016, India kaushikdeuti @ gmail. com; https: / orcid. org / 0000 - 0003 - 3319 - 3665
kaushikdeuti@gmail.com
text
Zootaxa
2022
2022-02-21
5100
3
419
434
journal article
20571
10.11646/zootaxa.5100.3.6
94e84c9b-aaff-4947-ae84-663fa1baa862
1175-5326
6201791
3A4F2341-439E-4535-A9DA-603D5AA4C1F9
Euphlyctis jaladhara
sp. nov.
Holotype
:
ZSI
/
WGRC/2948
, an adult male (
SVL
37.8 mm
) collected by
BH Channakeshavamurthy
and team in
October 2017
from the surroundings of Thattekad Bird Sanctuary (
N 10.1272
;
E 76.6840
),
Kerala
,
India
.
Paratypes
:
ZSI
/
WGRC/2889
, an adult female (
SVL
47.3 mm
) and
ZSI
/
WGRC/2946
,
an adult female (
SVL
62.1 mm
), collection details same as
holotype
.
Lineage diagnosis:
Euphlyctis jaladhara
sp. nov.
is diagnosed phylogenetically as a member of the larger ‘
Euphlyctis
clade’ (
Fig. 2
). The new species shows a possible sister relationship to the clade comprising
E. ehrenbergii
with a genetic distance of 6.4% and
E. kalasgramensis
with a genetic divergence of 5.4% for the mt 16S rRNA gene (
Fig. 2
). Under field conditions,
E. cyanophlyctis
could be a syntopic congener in the peripheral zone of its range of distribution. For the mt 16S rRNA gene,
Euphlyctis jaladhara
sp. nov.
exhibits a genetic divergence of 4.4% with
E. cyanophlyctis
. For the nuclear Tyrosinase gene,
Euphlyctis jaladhara
sp. nov.
(
AB
489017.1) shows a genetic divergence of 0.9% with
E. cyanophlyctis
(
MT
782272.1).
FIGURE 2.
Maximum Likelihood (ML) tree for species of
Euphlyctis
and
Phrynoderma
based on a concatenated dataset of 575 bp of mitochondrial 16S rRNA gene and 699 bp of nuclear Tyrosinase gene.
Field Diagnosis:
Under field conditions among the skittering frogs,
Euphlyctis jaladhara
sp. nov.
is sympatric with
P. kerala
and
P. karaavali
in the south of Palghat gap. In the north of the Palghat gap, the new species is sympatric with
P. aloysii
and
P. karaavali
. The new species could be sympatric with
E. cyanophlyctis
(
Fig. 6
) in the Western Ghats region of Madikeri (based on the two sequences of
Euphlyctis jaladhara
sp. nov.
included in the studies of
Kurabayashi
et al.
2005
and
Hasan
et al.
2014
labeled as
E. cyanophlyctis
). Other than
E. cyanophlyctis
, no sympatric congeneric species could be encountered in field conditions. Additionally,
Euphlyctis jaladhara
sp. nov.
can be easily distinguished from the rest of the skittering frogs by a combination of morphological characters like male adult size small (
SVL
,
33.7 mm
to
37.8 mm
) and large females (
SVL
,
47.3 mm
to
62.1 mm
); head length equal to head width; acutely pointed snout; snout equal to eye diameter; angled canthus rostralis with flat loreal region; inter-orbital distance half of the upper lid width; distinct tympanum equal to eye diameter; first finger longer than the second finger; pre-pollex tubercle and supernumerary tubercles absent in hand; tibio-tarsal articulation reaches nostril; porous warts absent; distinct black line from the back of the shoulder to groin separating the dark dorsal colour and ventral white colour; ventral side of males white and females spotted; back of the thigh with a single white band (see morphological characters key to members of
Euphlyctis
below).
Geography:
The species is known from freshwater bodies of the western coastal plains of peninsular
India
.
Description of
Holotype
(ZSI/WGRC/2948) (
Fig. 2
,
Fig. 3
,
Fig. 4
)
A small sized skittering frog (SVL =
37.8 mm
) with lean, elongated, and squat body; head width subequal to head length (HW =
14.3 mm
; HL =
13.9 mm
); snout acutely pointed (SL = 4.0 mm) and subequal to eye diameter (EL =
4.7 mm
); canthus rostralis angled, loreal region flat, inter-orbital space flat (IUE =
1.4 mm
) half of the upper lid (UEW =
2.9 mm
) and subequal to internarial distance (IN =
1.1 mm
); distance between the back of eyes 1.7 times more than front of eyes (IFE =
5.2 mm
; IBE =
9.2 mm
); nostrils oval, on the lateral sides and nearer to the tip of snout; symphysial knob moderate; tympanum distinct, visible below the supratympanic fold (TYD =
3.6 mm
) and close to the eye (TE =
0.4 mm
); vomerine ridges present, weak; tongue bifid without a papilla.
Forearm robust and short (FLL =
7.5 mm
), slightly shorter than the hand (HAL = 9.0 mm); fingers thin without any dermal fringes, first finger (FL1 =
3.3 mm
) longer than the second finger (FL2 =
2.7 mm
) and shorter than the third finger (TFL =
4.4 mm
), tips blunt without any enlarged discs, webbing between fingers absent; subarticular tubercles moderate, rounded and pre-pollex tubercle and supernumerary tubercles absent.
Hind limbs long, touch each other when folded at right angles to the body, and tibio-tarsal articulation reaches nostril; femur length subequal to tibia length (FL =
20.9 mm
; TiL =
19.4 mm
); foot length is 1.9 times tarsus length (FOL =
19.7 mm
, TaL =
9.9 mm
), relative toe length I<II<III<V<IV (FTL =
11.7 mm
); inner toe minute (ITL =
3.5 mm
), webbing complete, no phalanges free on toes; inner metatarsal tubercle (IMT = 2.0 mm) distinct, outer metatarsal tubercle, supernumerary tubercles and tarsal tubercle absent.
In preservative (
Fig. 4
), overall skin on the dorsum smooth uniform with few minute projected granular spots, but concentrated at the region of the vent; ventrally smooth on throat, belly, hands, and back of thighs. Porous warts absent. Colour on the dorsum dark, stone black mottled patches on the light grey background; limbs not barred but thighs faintly barred. On the lateral sides, a distinct black line from the back of the shoulder to the groin separates the dark dorsal colour from the ventral white colour. Ventrally, throat, belly, forehand, thighs, tibia, and tarsus uniform cream white, hand and foot light grey. Back of thigh with a single white band.
In life (
Fig. 3
), dorsal upper surface of the forearm, hand, thigh, tibia, tarsus, and entire dorsum light cream background with olive green irregular blotched pattern. Lateral sides of the body with a distinct black line from the back of shoulders to the groin separating the upper dark colour from the ventral light colour. Eye diamond-shaped, pupil black, iris golden brown (
Fig. 3
).
Secondary sexual characters and sexual dimorphism (
Fig. 4
): Adult males have a pair of dark black external vocal sacs at the lateral sides of the throat (
Fig. 4
), but the nuptial pads are absent on the first finger. In general, females have grey spots on the entire ventral region (as compared to the white ventral side of the males) (
Fig. 4
).
FIGURE 3.
A) Male and B) Female of
Euphlyctis jaladhara
sp. nov.
in life.
FIGURE 4.
Holotype of
Euphlyctis jaladhara
sp. nov.
A) dorsal view; B) ventral view (ZSI/WGRC/A/2948).
Additional information from
paratypes
(and other reference collections) and variations: Morphological data are given in
Table 1
.
Paratypes
range from
47.3 mm
to
62.1 mm
in
SVL
; all the males in the collections ranged from
33.7 mm
to
37.8 mm
in
SVL
, and females ranged from
40.8 mm
to
62.1 mm
in
SVL
. The external morphological characters of
holotype
and
paratypes
were similar to the reference collections except for the colour characters for sexual dimorphism (
Fig. 5
)
.
FIGURE 5.
Type series of
Euphlyctis jaladhara
sp. nov.
dorsal and ventral view, A) (holotype, ZSI/WGRC/A/2948 (male); B) paratype ZSI/WGRC/A/2946 (female); C) paratype ZSI/WGRC/A/2889) (female).
Etymology:
The new species epithet is derived from the Sanskrit word Jaladhârâ (jala=water + adhâra = reservoir), meaning ‘deposit of water’. The new species is treated as a symbol of freshwater resources, as this frog is seen floating on the surface of freshwater ponds / streams during both day and night time. The species epithet is treated as a noun in apposition to the generic name. Suggested common name: ‘Jaladhara skittering frog’.
Distribution and Natural history:
Euphlyctis jaladhara
sp. nov.
is known specifically from Thattekad,
Kochi
, and
Mangalore
(Konaje, Padil) based on the genetic sequences. Our field studies suggest the presence of the species throughout the western coastal plains (
Kerala
coastal plain,
Karnataka
coastal plain, and Konkan coastal plain) all along the foothills of the Western Ghats from Thattekad to Daman Ganga River side, Khanvel, Nagar Haveli, and Diu Union Territories of
India
. Looking at the distribution range, it appears that the species could be present in any freshwater bodies from Kanyakumari to Diu Union Territories of
India
. Although the species is well documented in the western coastal plains of peninsular
India
, its elevational preference all along the westerly slopes of the Western Ghats needs to be assessed with additional field explorations.
In earlier studies, the two sequences AB167938.1 (
Kurabayashi
et al.
2005
) and AB530596.1 (
Hasan
et al.
2014
) labeled as
E. cyanophlyctis
are similar to the sequences of
Euphlyctis jaladhara
sp. nov.
, generated in this study. Those two sequences along with the new sequences generated in this study formed a clade which indicates the possibilities of the new species in sympatry with
E. cyanophlyctis
in the periphery of their range of distribution.