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Two new species of Raorchestes (Anura: Rhacophoridae) from the Silent Valley National Park in the Nilgiri Hills of the Western Ghats, India

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Two new species of rhacophorid bush frogs of the genus Raorchestes are described from the tropical montane wet forests in the Silent Valley National Park in the Nilgiri Hills, a high horst in the Western Ghats, India. Both species can be differentiated from their congeners by morphological and bioacoustic characters as well as differences in the mitochondrial 16S gene. Advertisement calls of the two new species are provided and tentative insights into the phylogenetic position discussed. Despite recent revisions of this genus from the Western Ghats, and the fact that the Silent Valley National Park is one of the most important and well-surveyed protected areas, the results of this study highlight the overlooked diversity in this area.
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30 JUNE 2016
German Journal of Herpetology
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Z, A., V. P. C, B. C, B. R. A, J. K. M, D. V. R  R. K. A: Two
new species of Raorchestes (Anura: Rhacophoridae) from the Silent Valley National Park in the Nilgiri Hills of the
Western Ghats, India ........................................................................................................................................................................... 63
D, J. M., M. M  P. Y I: A new small montane species of Philautus (Amphibia: Anura:
Rhacophoridae) from Gunung Kinabalu, Sabah, Malaysia (Borneo) .......................................................................................... 77
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Two new species of Raorchestes from the Nilgiri Hills
All articles available online at
© 2016 Deutsche Gesellscha für Herpetologie und Terrarienkunde e.V. (DGHT), Mannheim, Germany
SALAMANDRA 52(2) 63–76 30 June 2016 ISSN 0036–3375
Two new species of Raorchestes (Anura: Rhacophoridae)
from the Silent Valley National Park in the Nilgiri Hills
of the Western Ghats, India
A Z, V P C, B C,
B R A, J K. M, D V. RR K A,
1) Beagle, Chandakunnu, Wayanad, Kerala 673121, India
2) School of Biology, Indian Institute of Science Education and Research, iruvananthapuram, Kerala 695016, India
3) SciGenom Research Foundation, Kamaraj Avenue, Kasturibai Nagar, Adyar, Chennai, Tamil Nadu 600020, India
4) Vilayilveedu, Prathibha Jn., Mudapuram, Chirayinkeezhu, Kerala 695304, India
5) Karakkattupeedicayil, Edakkara, Malappuram, Kerala 679331, India
6) Valiyaparampil House, Kuzhimattom, Kottayam, Kerala 686533, India
7) Current Address: Natural History Museum, Biodiversity Institute, and Department of Ecology and Evolutionary Biology,
e University of Kansas, 1345 Jayhawk Boulevard, Lawrence, KS 66045-7561, U.S.A.
8) Madras Crocodile Bank Trust/ Centre for Herpetology, Mamallapuram, Tamil Nadu 603104, India
Corresponding author: R K A, e-mail:
Manuscript received: 6 August 2015
Accepted: 2 February 2016 by M F. B
Abstract. Two new species of rhacophorid bush frogs of the genus Raorchestes are described from the tropical montane
wet forests in the Silent Valley National Park in the Nilgiri Hills, a high horst in the Western Ghats, India. Both species can
be dierentiated from their congeners by morphological and bioacoustic characters as well as dierences in the mitochon-
drial S gene. Advertisement calls of the two new species are provided and tentative insights into the phylogenetic posi-
tion discussed. Despite recent revisions of this genus from the Western Ghats, and the fact that the Silent Valley National
Park is one of the most important and well-surveyed protected areas, the results of this study highlight the overlooked
diversity in this area.
Key words. Amphibia, bush frog, species description, South Asia, protected area, montane habitat, taxonomy.
e rhacophorid genus Raorchestes B, S,
D, D  B,  is a species-rich assem-
blage of bush frogs, which are found from the southern tip
of the Indian Peninsula to northeastern India, Indochina,
and mainland Southeast Asia (B et al. , F ).
Raorchestes, which has been shown to be the sister clade
of the primarily Sri Lankan Pseudophilautus by B et al.
(), is most diverse in Indias Western Ghats, a highland
region in which many novel endemic species are still being
discovered (D et al. ). A total of  Raorchestes
species are known from the Western Ghats, including nu-
merous taxa that are restricted to isolated sky islands (e.g.,
B  B , B et al. , Z et al.
, S et al. , P et al. , V-
 et al. ). Concerning relationships in the speciose
genus Raorchestes, several recent phylogenetic studies indi-
cate the presence of two prominent clades and several sub-
clades within the genus (B et al. , A et al.
, V et al. ). V et al. ()
called one of the two prominent clades Clade ‘N’, which
comprises species that are distributed predominately to the
north of a prominent geological gap called the Palakkad
Gap, while the other clade is composed of species primarily
distributed to the south of this gap.
A recent expedition to the higher altitudes of the Si-
lent Valley National Park in the Nilgiri Hills of the West-
ern Ghats provided opportunities to observe and identi-
fy two novel taxa of Raorchestes in addition to two species
that were previously described from the area (R. signatus
and R. tinniens). While R. signatus inhabits forest habitats,
R.tinniens is known from grasslands in the area of interest.
Of the two novelties, one is a green, semi-arboreal taxon
and the other a brown, ground-dwelling leaf litter taxon.
Herein, we compare these two taxa to closely related and
A Z et al.
sympatric Raorchestes species, and describe them as new
to science.
Materials and methods
Study area
e Western Ghats form a long north–south hill range
straddling the west coast of peninsular India, with a con-
spicuous gap that divides the range into two prominent
parts. is geological gap, called the Palakkad Gap, has
been recognized as a prominent biogeographical barrier
for amphibians ( B et al. ), shes (J et
al. ), mammals (R et al. ), and birds (R et
al. ). e section to the north of the gap is technically
the escarpment of a vast plateau, with several hill clusters
and horsts dotting the western margin of the Ghats (N
). e highest and most prominent amongst these is
the Nilgiri Hills, a broad massif with an average altitude of
, m a.s.l. with a western portion that rises to an aver-
age of , m a.s.l. (C  B ). From this
high western margin, the Nilgiri Hills descend steeply into
the Malabar coastal plains (Fig. ).
During the course of three eld trips (May , June
, May ) to the southwestern slopes of the Nilgiri
Hills, which is part of the Silent Valley National park, two
Raorchestes that were previously unknown from this area
were observed and collected that could not be assigned to
any described species in the genus. Morphological data
were recorded from  specimens for each species; they were
euthanised, xed in  formalin, and later transferred to
 ethanol. Measurements (rounded to . mm) and ter-
minology follow those of Z et al. () for adult
frogs. ese voucher specimens were deposited in the Nat-
ural History Museum, Trivandrum (TNHM), India.
Advertisement calls (vocalisations) were recorded with a
TASCAM HDP portable stereo recorder in uncom-
pressed WAV format at a sampling rate of . kHz and
 bit resolution. Call parameters were measured using the
R package of SEEWAVE (S et al. , R Develop-
ment Core Team ) and Raven© Pro . (Bioacoustics
Research Group, Cornell Lab of Ornithology ). Call
Figure 1. Map showing the type localities of Raorchestes silentvalley sp. n. (yellow dot) and R. lechiya sp. n. (red dot) in the Silent
Valley National Park, Kerala, India.
Two new species of Raorchestes from the Nilgiri Hills
analyses were standardized at a Fast Fourier transform
(FFT) frame length of  Hz, a time-grid overlap of ,
and Hann window type. A call is dened as the entire as-
semblage of acoustic signals produced in a given sequence
(D T ). A series of pulses (or notes)
is dened as a call when pulses form temporally distinct
segments that are separated by a return to the background
noise between each note (H et al. ). Ambient
temperature at the time of the recording was noted.
Molecular analysis
For molecular analyses, we extracted DNA from mus-
cle tissue of four individuals of the two novel Raorchestes
taxa with a Qiagen DNeasy kit. A ~-bp segment of mi-
tochondrial DNA, corresponding to the ribosomal subu-
nit (S rRNA) (F et al. ), was amplied through
a standard polymerase chain reaction (PCR) (P
). e sequences were deposited in GenBank under
the accession numbers KT, KT, KT &
KT. e combined sequence data from GenBank
(see Table ; with the exception of R. thodai due to lack
of sequences) were aligned with our sequencing outcomes
using the default parameters of the MUSCLE algorithm
(E ). Uncorrected p-distances for the partial S
rRNA gene between included Raorchestes species were cal-
culated with PAUP* . (S ) and visualized
as a heatmap using R (for individual values, see Appendix).
To obtain preliminary insights into the phylogenetic
position (tree not shown), we used the same Raorchestes
dataset of our p-distance analysis and included Pseudo-
philautus wynaadensis as the outgroup taxon. A Maximum
Likelihood (ML) tree was calculated using RAxMLv..
(S ; substitution model: GTR + G;  in-
dependent best-tree searches; rapid-bootstrapping algo-
rithm with  replicates). Calculations were based on an
alignment of  bp aer exclusion of ambiguous variable
and hypervariable sections of the analysed gene fragment
(–, –, , –, –).
Morphological analysis
e following measurements were taken with a digital cal-
liper (to the nearest . mm): snout–vent length (SVL,
from tip of snout to vent); greatest head width (HW, at an-
gles of jaws); head length (HL, from posterior edge of jaw
to tip of snout); interorbital width (IUE, shortest distance
between upper eyelids); upper eyelid width (UEW, greatest
width of the upper eyelid); snout length (SL, from ante-
rior border of eye to tip of snout); eye diameter (EL, hori-
zontal distance between orbital margins of eye); forelimb
length (FLL, from tip of elbow to proximal edge of palmar
tubercle); hand length (HaL, distance from proximal edge
of palmar tubercle to tip of third nger); thigh length (TL,
from vent to external edge of knee); shank length (ShL,
from external edge of the knee to tip of heel); tarsus length
(TaL, distance from heel to proximal edge of inner meta-
tarsal tubercle); foot length (FoL, from proximal edge of
inner metatarsal tubercle to tip of fourth toe). All measure-
ments are given in millimetres. Because it has been shown
that anurans have lost the rst (medial) nger of the hand,
the remaining four digits are numbered II through V, in
contrast to the traditional I through IV (S A-
 ).
Nomenclatural acts
e electronic edition of this article conforms to the re-
quirements of the amended International Code of Zoo-
logical Nomenclature, and hence the new names contained
herein are available under that Code of this article. is
published work and the nomenclatural acts it contains
have been registered in ZooBank, the online registration
system for the ICZN. e LSID (Life Science Identier) for
this publication is:AAF-
DDC-CA-BF-FFEEAD. e electronic edition
of this work was published in a journal with an ISSN, has
been archived, and is available from the following digital
In our exploratory phylogeny (results not shown), we nd
that both new species described here belong to the genus
Raorchestes, which is diagnosed solely by its unique mo-
lecular phylogenetic position within Rhacophoridae (B
et al. , A et al. ). Within Raorchestes, both
species belong to the same major clade called Clade ‘N’
sensu V et al. (). is is corroborated by
the results of the uncorrected p-distances calculated from
the mitochondrial alignment, which demonstrates that
species with highest genetic similarity to both novel taxa
described here occur north of the Palakkad Gap (Fig. ; Ta-
ble ). Consequently, we describe both taxa using morpho-
logical, molecular, and bioacoustics means and comment
on their distribution and ecology.
Raorchestes silentvalley sp. n.
(Fig. 3, 4; Table 2)
ZooBank LSID:DEF-C-D-
Suggested common name: Silent Valley bush frog
Holotype: TNHM (H) ../ (Figs A, ); adult male
(. SVL); collected from forest vegetation of  m in height
at Sispara (°’.’’ N, °’.’’ E) at , m a.s.l.,
Silent Valley National Park, Palakkad District, Kerala, by
A Z on  May .
A Z et al.
Table 1. Genetic similarity of Raorchestes silentvalley sp. n. and R. lechiya sp. n. with 51 congeners. Given are minimum (Min), maxi-
mum (Max), and mean (Mean) values of uncorrected pairwise sequence divergence, presented in % of ~570 bp of the 16S rRNA
gene; corresponding GenBank accession numbers are provided alongside the species names, and species marked with an “*” belong
to the Clade ‘N’; the species marked with a “+” is found outside of the Western Ghats. e analysed fragments of the 16S gene in
R.silentvalley sp. n. (KT359628 & KT359629) were identical (uncorr. p-distance 0%) and almost identical (0.21%) for R. lechiya sp.n.
(KT359622 & KT359623). See Appendix for uncorrected pairwise distance values (%) between all species.
Species R. silentvalley sp. n. R. lechiya sp. n.
No. Mean Min Max Mean Min Max
1R. charius (JX092691)* 7.45 7.36 7.55 7.15 6.98 7.31
2R. griet (JX092654)* 8.10 8.01 8.19 8.51 8.40 8.62
3R. coonoorensis (JX092716)* 8.15 8.06 8.24 9.11 8.90 9.32
4R. ravii (JX092720)* 7.96 7.86 8.05 8.26 8.06 8.45
5R. nerostagona (JX092661) 8.62 8.62 8.63 9.21 8.85 9.57
6R. blandus (JX092660) 9.98 9.89 10.08 9.54 9.25 9.83
7R. archeos (JX092675) 8.88 8.87 8.89 10.09 9.72 10.46
8R. chotta (JX092656) 8.22 8.21 8.23 8.82 8.61 9.02
9R. echinatus (JX092696)* 5.86 5.86 5.86 6.04 5.77 6.30
10 R. aviventris (JX092694)* 7.65 7.56 7.75 7.74 7.50 7.98
11 R. hassanensis (JX092673)* 8.23 8.14 8.33 7.91 7.67 8.16
12 R. ponmudi (JX092651)* 6.59 6.50 6.69 5.79 5.50 6.09
13 R. bobingeri (JX092680) 6.85 6.75 6.95 7.80 7.77 7.83
14 R. glandulosus (JX092665) 7.37 7.36 7.38 7.83 7.78 7.88
15 R. jayarami (JX092686) 7.07 6.97 7.16 8.00 7.78 8.22
16 R. akroparallagi (JX092650) 6.31 6.30 6.31 7.91 7.38 8.45
17 R. ghatei (JX092687)* 7.85 7.76 7.95 7.27 7.01 7.53
18 R. leucolatus (JX092669)* 8.00 7.99 8.01 8.40 8.39 8.40
19 R. tuberohumerus (JX092697)* 9.10 9.00 9.19 7.13 6.86 7.41
20 R. bombayensis (JX092657)* 8.75 8.65 8.84 7.26 6.99 7.54
21 R. terebans (JX092689)*+8.85 8.75 8.95 8.01 7.88 8.14
22 R. luteolus (JX092659) 5.42 5.42 5.43 6.70 6.21 7.19
23 R. travancoricus (JX092721) 6.49 6.48 6.50 6.66 6.18 7.14
24 R. marki (JX092719)* 5.28 5.18 5.37 4.74 4.66 4.83
25 R. chromasynchysi (JX092709)* 3.46 3.46 3.47 5.37 5.30 5.44
26 R. indigo (JX092678)* 5.46 5.37 5.56 4.08 4.00 4.17
27 R. agasthyaensis (JX092723) 5.65 5.65 5.66 6.03 5.76 6.31
28 R. kadalarensis (JX092702) 5.45 5.44 5.45 6.52 6.25 6.78
29 R. aureus (JX092672)* 4.90 4.80 4.99 2.39 2.22 2.55
30 R. signatus (JX092710)* 3.26 3.26 3.27 2.79 2.66 2.93
31 R. tinniens (JX092715)* 4.11 4.11 4.12 3.55 3.55 3.56
32 R. primarrump (JX092717)* 3.15 3.05 3.25 3.22 3.10 3.34
33 R. montanus (JX092690)* 3.45 3.44 3.46 3.12 3.10 3.14
34 R. crustai (JX092677) 7.33 7.32 7.34 7.42 7.08 7.75
35 R. graminirupes (JX092649) 5.63 5.62 5.64 5.06 4.65 5.47
36 R. johnceei (JX092679) 4.62 4.61 4.63 4.50 4.09 4.90
37 R. sushili (JX092684) 6.32 6.22 6.42 7.06 6.79 7.32
38 R. manohari (JX092674) 5.24 5.14 5.34 6.27 6.23 6.32
39 R. uthamani (JX092722) 5.34 5.24 5.43 6.15 6.11 6.19
40 R. chlorosomma (JX092681) 5.18 5.09 5.28 6.43 6.38 6.49
41 R. aviocularis (JX092682) 4.30 4.29 4.30 5.54 5.25 5.82
42 R. chalazodes (JX092676) 5.45 5.35 5.54 6.36 6.31 6.42
43 R. ochlandrae (JX092666) 5.38 5.28 5.48 6.16 6.13 6.19
44 R. kaikatti (JX092718) 4.44 4.35 4.54 5.60 5.53 5.68
45 R. kakachi (JX092704) 5.21 5.20 5.22 5.82 5.54 6.10
46 R. beddomii (JX092653) 5.33 5.23 5.43 5.31 5.30 5.32
47 R. theuerkau (JX092693) 6.88 6.78 6.98 6.64 6.59 6.69
48 R. munnarensis (JX092655) 5.42 5.32 5.52 6.34 6.27 6.41
49 R. resplendens (JX092683) 5.04 4.94 5.13 5.88 5.85 5.91
50 R. anili (JX092708) 4.69 4.59 4.79 5.75 5.57 5.93
51 R. dubois (JX092668) 3.80 3.70 3.89 4.84 4.84 4.85
Two new species of Raorchestes from the Nilgiri Hills
Paratype: TNHM (H) ../ (Fig. E); adult male (.
SVL), collected from foliage . m above the ground at the
type locality by R K A on  May .
Diagnosis: e genetic data (S rRNA) identies the new
species as a member of the genus Raorchestes. Raorchestes
silentvalley sp. n. diers from all known congeners by the
following combination of characters: a medium-sized (SVL
., N = ) green bush frog with shagreened dorsal skin
covered with small, horny, spiculate projections; bright yel-
low, granular ventral skin with large purplish black blotch-
es interspersed towards the posteroventer and thighs; tym-
panum indistinct, supratympanic fold faint; palpebral
membrane with pale green spots and blotches; palmar and
plantar surfaces shagreened; ngers without webbing, toes
half webbed; distinct advertisement call.
Description of holotype: An adult male of SVL . (Fig. );
head wider (.) than long (.); snout rounded in ventral
aspect, acuminate in lateral prole (Fig. C); snout length
(.) slightly greater than diameter of the eye (.); can-
thus rostralis sharp and obtuse, loreal region at; interor-
bital distance (.) greater than upper eyelid width (.);
tympanum indistinct; supratympanic fold weak, extending
from posterior margin of outer canthus to shoulder region;
lanceolate tongue lacking lingual papilla, with small, hard
region toward base; vomerine teeth absent; pupil horizon-
tal; palpebral membrane ornamented with pale green spots
(Fig. C); vocal sac single, median, and subgular.
Forelimb (.) shorter than hand (.); Fingers III, IV,
and V with lateral dermal fringes; subarticular tuber-
cles prominent, round, and single; supernumerary tuber-
cles present on ngers III, IV, and V; inner palmar tuber-
cles prominent, oval; discs well developed, expanded, and
broadened; relative lengths of ngers II < III < V < IV; web-
bings between ngers absent.
Hind limb long, shank (.) subequal to thigh length
(.); toes half webbed (Fig. D), extending from disc of
toe V to distal subarticular tubercle of toe IV; lateral der-
mal fringes present on all toes; subarticular tubercles well
developed, round, and single on all toes; supernumerary
tubercles present but indistinct; inner metatarsal tubercle
prominent, oval; outer metatarsal tubercle indistinct; rela-
tive lengths of toes I < II < III < V < IV.
Figure 2. Heatmap of pairwise uncorrected p-distances of the 16S rRNA gene of R. silentvalley sp. n., R. lechiya sp. n., and 51 Raorchestes
species from peninsular India. e colours red to green indicate low to high divergences. For respective Genbank accession numbers,
see Table 1.
A Z et al.
Skin of dorsum strongly shagreened with small, horny
spicules, and glandular projections that are more promi-
nent towards the posterior and lateral sides; venter granu-
lar; dorsal surface of forelimbs and hind limbs shagreen-
ed; planar and plantar surfaces uniformly shagreened
(FigsD, E). Small incision in the posterior surface of the
right thigh made for tissue sample.
Coloration of holotype in life: Dorsum uniformly bright
green with yellow-tipped glandular projections (Fig. A);
venter bright yellow with irregular dark purplish and black
patches along axillary margin of shoulder and on belly and
groins, where the blotches are broader; small yellow spots
or blotches interspersed in the broader purplish black
patches in the posterior parts of the venter; anterior region
Figure 3. Raorchestes silentvalley sp. n. (in life): A) vocalizing male; B) ventral coloration of a live individual (Paratype); C) spotted
pattern on palpebral membrane; D) and E) dorsal colour variation in other male individuals.
Table 2. Morphometric measurements (mm) of type specimens (all males). For abbreviations, see Materials and methods.
Raorchestes silentvalley sp. n.
TNHM (H) 12.6.18/53 27.1 11.3 9.8 4.8 2.9 4.0 3.8 6.2 7.9 14.7 14.3 7.6 12.1
TNHM (H) 12.6.18/54 26.8 11.6 9.2 4.0 2.3 4.4 4.2 6.4 7.6 14.8 14.2 7.1 10.8
Mean 27.0 11.4 9.5 4.4 2.6 4.2 4.0 6.3 7.8 14.8 14.3 7.4 11.5
Raorchestes lechiya sp. n.
TNHM (H) 12.6.18/55 19.8 8.4 8.2 3.2 2.1 3.5 3.3 4.3 5.6 11.1 11.2 6.3 7.2
TNHM (H) 12.6.18/56 21.1 8.6 7.3 3.3 1.7 3.7 3.2 5.3 5.0 10.3 10.6 6.3 7.7
Mean 20.5 8.5 7.6 3.2 1.9 3.6 3.3 4.8 5.3 10.7 10.9 6.3 7.5
Two new species of Raorchestes from the Nilgiri Hills
of thigh, posterior region of tibia, plantar surface grey to
purplish black; outer faces of limbs green, inner faces yel-
low; discs and distal phalanges of hands and feet purplish
grey; iris dark brown to cherry-red; palpebral membrane
with pale green spots and blotches; vocal sac yellow; ven-
tral surface of head greenish yellow.
Coloration of holotype in preservative (aer three years
of preservation): Dorsum bluish grey (Fig. A); venter o-
white with irregular grey to black patches on belly and tibia
(Fig. B); forelimbs grey to black above, ngers II and III
o-white; hands and feet greyish black; anks o-white;
groin and posterior parts of thighs black.
Dierential diagnosis: In general appearance, the green
coloration of Raorchestes silentvalley sp. n. dierentiates it
from all closely allied species as demonstrated in our p-
distance analysis (Fig. ) such as R. primarrump, R. mon-
tanus, and R. signatus, all of which show variable shades
of brown coloration. It could however be confused with
some other green Raorchestes, but can be dierentiated
as follows: It is distinguished from R. beddomii by hav-
ing contrasting purplish black blotches on a bright yel-
low venter (vs. whitish venter and yellow throat) and hav-
ing a spiculate (vs. smooth) dorsum. It diers from male
R. chrom asynchysi, in having deep red eyes with green
spots and blotches on palpebral membrane (vs. dark gold-
en-brown eyes with a uniform transparent palpebral mem-
brane) and in the shagreen (vs. smooth) plantar surfaces.
Raorchestes silent valley sp. n. is distinguished by its larger
male size (mean SVL . mm, N = ) from R. bobingeri
(mean SVL . mm), R. glandulosus (mean SVL .mm)
and R.akro parallagi (mean SVL . mm); uniform green
colour in the loreal region and on dorsal surface of limbs
(vs. yellow loreal region in R. glandulosus; yellow or or-
ange colour on upper arms and posterior region of limbs
in R.bobin geri and R. jayarami), horny spiculate dorsal
skin (vs. smoothly shagreened dorsal skin in R. bobingeri,
R. jaya rami, R. glandulosus, and R. akroparallagi); half-
webbed toes (vs. basally webbed in R. akroparallagi); and
green blotches on palpebral membrane (vs. uniform trans-
parent palpebral membrane in R. bobingeri, R. glandulo-
sus and R.akro parallagi). Raorchestes silentvalley sp. n. dif-
Figure 4. Holotype of Raorchestes silentvalley sp. n. (TNHM (H) 12.6.18/53): A) dorsal view; B) ventral view; C) lateral view of head;
D) ventral view of right foot; E) ventral view of right hand.
A Z et al.
fers from R. aviventris by its smaller size (vs. large size of
.–.mm), green blotches on palpebral membrane (vs.
uniform palpebral membrane), absence of lingual papilla
on tongue (vs. presence), and half-webbed toes (vs. basally
webbed). Raorchestes silentvalley sp. n. can be distinguished
from R.indigo by the presence of green blotches on palpe-
bral membrane (vs. uniform palpebral membrane), and
dorsal portions of ngers and toes grey (vs. dorsal faces
of ngers and toes green). It diers from R.tinniens by be-
ing green with purplish grey phalanges (vs. brownish, with
brown distal phalanges except for ngers II and III, which
are yellow). Raorchestes silentvalley sp. n. can also be dis-
tinguished from the sympatric R. signatus primarily by its
much smaller adult male size (vs. average adult male SVL
>  mm), and in being a green frog (vs. variably mottled
ranging from yellow to brown and red).
Variation: e colour pattern of Raorchestes silentvalley
sp.n. varies markedly. is is apparent in the type speci-
mens, and eld observations of these anurans revealed
variations of green colour across individuals. e holotype
was uniform green dorsally in life. In contrast, the dor-
sum of the paratype (Fig.E) was bright green with black
blotches and spots; some of the spots and blotches were
connected in a reticulated pattern, and each blotch had
a paler border. eses markings extended onto the limbs
as well. e dorsal face of a third individual (Fig. D) was
darker green with pale green spots, and each spot had a
dark border; the anks were immaculate. e ventral sides
of all individuals were yellow and bore greyish or purplish
black blotches or streaks.
Etymology: e specic epithet silentvalley refers to the Si-
lent Valley National Park in Kerala, India, where the spe-
cies was observed and collected.
Distribution and Natural History: us far, Raorchestes
silent valley sp. n. has been recorded only from the montane
wet forests (Figs A, B) of the southwestern slopes of the
Nilgiri Hills (Fig. ). e species was observed at Sispara
and the higher areas of udukki, both of which are situated
in the Silent Valley National Park in Kerala at altitudes rang-
ing between , and , m a.s.l. Vocalising individuals
were perched –. m above the forest oor on the branch-
es and foliage of understorey shrubs (dominated by Strobi-
lanthes lawsonii and occasionally by S. lanata) (Fig. C) and
small tree saplings, in May. Several vocalising males were
observed with blood-sucking leeches attached to them.
Genetics: e mean genetic dierence in the sampled re-
gion of the S rRNA gene between Raorchestes silentval-
ley sp. n. and  Western Ghats congeners ranged from
.−. (Table ). e uncorrected pairwise sequence
dierences to the genetically most similar species were as
follows: R. primarrump (mean: .), R. signatus (.),
R. montanus (.), and R. chromasynchysi (.), re-
spectively, all of which belong to Clade ‘N’ as demonstrated
by V et al. (). Our preliminary phyloge-
netic analysis suggests R. silentvalley sp. n. to be sister to
the R. chromasynchysi species complex identied in V-
 et al. ().
Advertisement call: A total of four advertisement calls from
three males were recorded at the type locality. Recordings
were made at night immediately aer light showers at an
ambient temperature of .–°C. e frogs called in cho-
rus at seemingly regular intervals. e advertisement call of
Raorchestes silentvalley sp. n. (Fig. A) comprises of a series
of high-frequency pulses (, Hz), approximately . s
apart on average, and the mean inter-call interval is . s
(n = ). ere is an average of – rapid pulses in each call,
increasing in amplitude from the initial pulse to the last.
e mean duration of a call was . s (n = ). All harmon-
ics are multiples of the fundamental frequency. e note
rate was ./sec. In comparison, its sister taxon, R. chrom-
asynchysi, has a call composed of – pulses (,Hz) on
average (Fig. B), with a call duration of .s (n = ) and
a mean inter-call interval of . s (n= ).
Figure 5. Comparative spectrograms (top) and corresponding oscillograms (bottom) of single notes of the advertisement calls on the
same time scale of R. silentvalley sp. n. (A) and R. chromasynchysi (B).
Two new species of Raorchestes from the Nilgiri Hills
Raorchestes lechiya sp. n.
(Figs 7, 8; Table 2)
ZooBank LSID:AB-BC--
Suggested common name: Lechiyappans bush frog
Holotype: TNHM (H) ../ (Figs A, ); adult male
(. SVL); collected from forest understorey vegetation
at Sispara (°’.’’ N, °’.’’ E) at , m a.s.l.,
Silent Valley National Park, Palakkad District, Kerala, by
A Z,  May .
Paratypes: TNHM (H) ../; adult male (. SVL);
collected along with the holotype by A Z.
Diagnosis: Its genetic data (S rRNA) identies the new
species as a member of the genus Raorchestes. Raorchestes
lechiya sp. n. can be distinguished from all known conge-
ners by the following combination of characters: a small-
sized (mean SVL ., N = ) pale brown bush frog with
a granular dorsum bearing small, horny spicules; snout
rounded in ventral view; distinct tympanum and supra-
tympanic fold; dark brown loreal and tympanic regions;
bicoloured eye with upper third copper-coloured and low-
er two-thirds dark brown; dark reticulated patterns on
the venter; groin, anterior and posterior regions of thighs
brown with white spots; basally webbed toes; distinct ad-
vertisement call.
Figure 6. Habitat of Raorchestes silentvalley sp. n. and R. lechiya sp. n.: A) Shola-grassland ecosystem (which is a climax matrix of
tropical montane grassland and forests) in the upper Nilgiri Hills, at Sispara in the Silent Valley National Park; B) montane evergreen
forest where both new species were located and collected; C) undergrowth of Stroblianthes lawsonii, perched upon which many vocal-
izing male individuals of both species were observed.
A Z et al.
Description of holotype: An adult male of SVL . (Fig. );
head wider (.) than long (.); snout rounded in ventral
aspect, acuminate in lateral prole (Fig. C); snout length
(.) subequal to horizontal diameter of the eye (.); can-
thus rostralis sharp, loreal region concave; interorbital dis-
tance (.) greater than upper eyelid width (.); tympa-
num distinct; supratympanic fold well developed, extend-
ing from the outer canthus to the region of forelimb; lan-
ceolate tongue with lingual papilla; vomerine teeth absent;
pupil horizontal; vocal sac single, median, and subgular.
Forelimb (.) shorter than hand (.); ngers III, IV,
and V with lateral dermal fringes; subarticular tuber-
cles prominent, round, and single; supernumerary tuber-
cles present on ngers III, IV, and V; inner palmar tuber-
cles prominent, oval; discs well developed, expanded, and
broadened; nger webbing absent; relative lengths of n-
gers II < III < V < IV.
Hind limb moderately long, shank length (.) sub-
equal to thigh (.); toes basally webbed (Fig. D), extend-
ing from the distal subarticular tubercle of toe V to sec-
ond subarticular tubercle of toe IV; lateral dermal fringes
present on all toes; subarticular tubercles well developed,
round, and single on all toes; supernumerary tubercles
present but indistinct; inner metatarsal tubercle promi-
nent, oval; outer metatarsal tubercle weakly developed; rel-
ative lengths of toes I < II < III < V < IV.
Figure 7. Male Raorchestes lechiya sp. n. (in life): A) holotype (TNHM (H) 12.6.18/55); B) vocalizing male (not collected); C) male in
amplexus (TNHM (H) 12.6.18/55) with a female (not collected).
Two new species of Raorchestes from the Nilgiri Hills
Skin of dorsum weakly shagreened with numerous
small, weakly developed horny spicules, snout and head
weakly shagreened, gradually turning more granular to-
ward the posterior regions; venter highly granular; dor-
sal surfaces of fore- and hind limbs granular; planar and
plantar surfaces weakly shagreened (Figs D, E). Small in-
cision in the posteroventral surface of the right thigh made
for tissue sample, partially obscured due to preservation.
Coloration of holotype in life: Dorsum pale brown, pal-
er towards the head and snout; loreal and tympanic regions
dark chocolate brown; a faint, dark, irregular band in the
interorbital region; and two short, curved, parallel, brown
bands on the dorsum (Fig. A); groin and anterior and pos-
terior margins of the thighs with faint whitish spots; poste-
rior face of thigh with dark reticulations suused with pale
whitish spots; dorsal face of thighs and shanks pale brown
with dark brown transverse bands; venter pinkish white
with brown vermiculations on throat, chest, and forelimbs,
and, faintly, on the hind limbs; iris bicoloured with upper
third copper-coloured and lower two-thirds dark brown.
Colour of holotype in preservative (aer three years of
preservation): Dorsum greyish brown (Fig. A); venter o-
white with irregular brown vermiculations on throat, chest,
and limbs (Fig. B); dorsal face of limbs greyish-brown;
ngers II and III white; hand and foot brown; anks brown
with darker and paler vermiculations and blotches; groin
and anterior and posterior parts of thighs brown with pale
whitish spots.
Dierential diagnosis: Raorchestes lechiya sp. n. is a distinctly
brown species; it could most likely be confused with R. chloro-
somma, which occurs south of the Palakkad Gap (andbe-
longs to the southern clade as identied by V
), and R. archeos, which occurs in the Agasthyamala
Hills and on the Periyar Plateau, likewise south of the Palak-
kad Gap. e new species diers from R. chlorosomma by
its small adult male size (vs. medium adult male SVL .–
.mm), dark vermiculations on the throat and chest on
a predominantly pinkish white ventrum (vs. pale, uniform
whitish throughout), posterior margin of thigh with pale
spots on a dark brown background (vs. uniform brown),
dorsum granular, covered with spicules (vs. smoothly sha-
greened), presence of a lingual papilla on tongue (vs. no lin-
gual papilla on tongue), and by the iris being lighter copper-
coloured above and dark brown below (vs. metallic-green
eyes in R. chlorosomma). Raorchestes lechiya sp. n. diers
from R. archeos by its rounded, acuminate snout (vs. acutely
pointed), dorsum granular, covered with several small horny
Figure 8. Holotype of Raorchestes lechiya sp. n. (TNHM (H) 12.6.18/55): A) dorsal view; B) ventral view; C) lateral view of head;
D)ventral view of right foot; E) ventral view of right hand.
A Z et al.
spicules (vs. sparsely spiculate shagreened), tongue with a
lingual papilla (vs. without a lingual papilla), and bicoloured
eyes (vs. uniformly golden-brown coloured). Raorchestes
lechiya sp. n. could also be confused with R. chromasynchy-
si, R.ravii, R.charius, R. coonoorensis (all of which also oc-
cur in the Nilgiri Hills, but are not sympatric) and R. tin-
niens. It diers from R. chromasynchysi by having dark lo-
real and tympanic regions (vs. pale and similar to the over-
all body colour), and a mottled throat and chest (vs. plain),
and bicoloured eyes (vs. uniformly gold-coloured). It diers
from R. ravii by having a darker loreal region as compared
to the dorsum (vs. uniform colour throughout the loreal re-
gion and dorsum), and by possessing bicoloured eyes (vs.
uniformly golden-brown coloured). It can be dierentiat-
ed from R. charius by its small adult size (vs. medium size)
and from R. charius and R. coonoorensis by having a more
granular dorsum with small spiculate projections and whit-
ish spots in the groin and anterior and posterior regions of
the thighs (vs. dorsum with prominent spiculate and tuber-
culated projections and large yellow or brown blotches on
the groin and thighs in R. charius and R.coonoorensis). Fur-
thermore, R. lechiya sp. n. is a robust frog (vs. slender elon-
gate in R. coonoorensis). It diers from R. tinniens by having
a pale venter with brown vermiculations and ngers II and
III being white (vs. plain yellowish white ventrum and n-
gers II and III yellow). Apart from these species, it can dis-
tinguished from the sympatric R. signatus primarily by its
much smaller adult male size (vs. average adult male SVL
>  mm), and by having a rounded snout in ventral view
(vs. pointed). Raorchestes lechiya sp. n. diers from R. aureus
primarily in possessing bicoloured iris (vs. uniformly golden
iris) and in having dierentially darker loreal and tympanic
regions compared to the dorsal surface of the head (vs. uni-
formly coloured dorsal, loreal, and tympanic regions). Fi-
nally, R. lechiya sp. n. can be distinguished from R. silentval-
ley sp. n. by its brown coloration, extent of webbing (more
developed in R. silentvalley sp. n.), smaller size, dierences
in call characteristics, and habitat use (forest understorey in
R.lechiya sp. n. and midstorey in R. silentvalley sp. n.).
Variation: Raorchestes lechiya sp. n. exhibits minor dier-
ences in colour pattern among individuals. e paratype
diers from the holotype by being dorsally covered with
large black spots and lacking the two short parallel dark
Etymology: e species name is a tribute to the late Mr.
Lechiyappan of the Mudugar tribe, a forest tracker at Si-
lent Valley National Park. He was instrumental in the early
conservation undertakings of the Silent Valley Movement,
which eventually led to the declaration of the area as a Na-
tional Park.
Distribution and Natural History: Raorchestes lechiya sp. n.
was found only in the upper reaches of the southwestern
slopes of the Nilgiri Hills (Fig. ) at altitudes ranging from
,–, m a.s.l. We found the species inhabiting the
leaf litter and understorey vegetation in montane wet for-
ests (Figs A, B). We also observed individuals vocalising
from branches of shrubs at an average height of  m from
the ground, as well as an amplectant pair (Fig. C).
Genetics: e mean genetic dierence in the sampled re-
gion of the S rRNA gene between Raorchestes lechi-
ya sp. n. and  Western Ghats congeners ranged from
.−. (Table ). e uncorrected pairwise sequence
dierences to the genetically most similar species were
as follows: R. aureus (mean: .), R. signatus (.),
R.montanus (.), R. primarrump (.), respectively,
and R. chlorosomma (.) to which it is morphological-
ly similar. Our preliminary phylogenetic analysis suggests
R. lechiya sp. n. to be the sister species of R. aureus and
nested in Clade ‘N’.
Advertisement call: A total of three advertisement calls
from two males were recorded at the type locality. Record-
ings were made at night immediately aer light showers
at an ambient temperature of .–°C. e advertisement
call of Raorchestes lechiya sp. n. (Fig. A) is a low “treek”
Figure 9. Comparative spectrograms (top) and corresponding oscillograms (bottom) of single notes on the same time scale of the
advertisement calls of R. lechiya sp. n. (A) and R. aureus (B).
Two new species of Raorchestes from the Nilgiri Hills
call, which is repeated at intervals of . s (n = ) on av-
erage. A call on average comprised – rapid pulses, ap-
proximately . s apart on average. e mean duration
of a call was . s (n = ) and the fundamental frequency
,Hz. e pulse rate was ./s. In comparison, its pu-
tative sister taxon, R. aureus, has a call comprising a single
pulse (, Hz) with a mean duration of . s (n = ) and
an inter-call interval of . s (Fig. B).
Our explorations in the montane wet forests around the
peak of Sispara Betta (in the Walakkad section of the Si-
lent Valley Forest Range) and the udukki section (Bha-
vani Forest Range) resulted in the discovery of two new
species of bush frogs. is raises the number of described
Raorchestes species in the Western Ghats to  (we have
identied R. emeraldi as a junior synonym of R. aviven-
tris; A et al. ), making it the most speciose an-
uran genus in the region.
Preliminary phylogenetic results (tree not shown)
place both species described here in the northern clade
of Raorchestes (Clade ‘N’ of V et al. ), re-
ecting their distribution north of the Palakkad Gap. Even
though both new species occur in the same habitat at alti-
tudes above , m a.s.l., R. silentvalley occupies the up-
per layers of the forest understorey and lower midstorey
on leaves and branches of small trees during the breeding
season, whereas R. lechiya is found on lower vegetation
and leaf litter on the forest oor. Both species are currently
known only from within the Silent Valley National Park
and likely endemic to the upper sections of the western and
southwestern slopes of the Nilgiri Hills.
Genetically, R. silentvalley sp. n. has a divergence of
> in the S unpaired p-distance sequence from all oth-
er congeners (Table ). It is most similar to R. chromasyn-
chysi, which is found at lower altitudes without zone over-
lap and can be distinguished by morphological and vocal
characters (the R. silentvalley sp. n. call is composed of –
rapid high-frequency pulses at , Hz as opposed to –
slower pulses at a slightly higher frequency of , Hz in
R.chrom asynchysi). Raorchestes lechiya sp. n. has a lower
divergence compared to the most similar R. aureus (.).
Preliminary phylogenetic results place the new species sis-
ter to R. aureus, but R. lechiya sp. n. can be delimited by a
combination of dierences in male vocalisation characters
(R. lechiya sp. n.: call comprising – rapid pulses at a fre-
quency of , Hz versus a single pulse call at , Hz in
R. aureus) and morphology. Moreover, both species dier
in their distribution, with R. lechiya sp. n. being restricted
to the higher reaches of the Nilgiri Hills, while R. aureus is
found only in the upper reaches of the Siruvani Hills across
the Attappadi Valley (see Fig. ). Morphological, bioacous-
tic, distributional, and ecological data have been signicant
for diagnosing both novel species. Although neither has so
far been recorded from outside the park, diligent survey ef-
forts in neighbouring regions such as New Amarambalam,
Upper Bhavani, and the slopes to the south of the Kundah
Range may provide supplemental distributional data.
e declaration of the area now known as Silent Val-
ley National Park in  followed in the wake of a land-
mark national and international debate on the relative im-
portance of human development versus the protection of
natural resources that ensued when the government pro-
posed to construct a dam in the area in  (M
). e scientic community responded quickly with a
preliminary but thorough study of the area’s biodiversity
and fragile ecology, thereby providing information that en-
abled activists to rally favour for the area, its being exempt-
ed from human development, and leading to the abandon-
ment of the Silent Valley hydroelectric project (G
G ). e dedicated interest in the area result-
ed in the discovery and description of amphibian novel-
ties such as Micrixalus thampi, Duttaphrynus silentvalley-
ensis, Ghato phryne rubigina, and Ichthyophis longicephalus
(P , , P  P ) from the
area that is today classied as the Silent Valley National
Park. Our addition of two new bush frog species under-
scores the importance of this national park and the region
in general as a vital repository of irreplaceable biodiversity
worthy of the struggle of the past, as well as preservation
for the future.
We thank the Kerala Forest Department for providing access and
collection permits to the rst and last authors, respectively (WL
-/). We also are grateful to S. S, former Division-
al Forest Ocer of the Silent Valley National Park, for making all
necessary arrangements for this expedition. We are indebted to V-
 M. (Assistant Conservator of Forests), P K
(Conservator of Forests), J M. (Range Forest Ocer), K. K.
S K (Assistant Conservator of Forests), R K. P
(Wildlife Assistant), and all ocial and eld sta who facilitated
our stay in the park; R C, N. P. J, P. K. U
and S for their unwavering support and encour-
agement provided during our survey; and to U P. K. and S-
 D, whose support and photographs are very much appre-
ciated. anks also due C H, T B, and
A  M B for their help with the call analy-
ses, to A Z and V O. for help with sequenc-
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Z, A., K. P. D, E. K, S. D, D. V.
R, C. R, M. J. P  S. K ():
Nine new species of frogs of the genus Raorchestes (Amphibia:
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Supplementary material
Additional information is available in the online version of this
article at
 Supplementary table. Uncorrected pairwise distances () for
S mtDNA gene fragment between  species of Raorchestes.
... Altogether, what transpired was a spate of new species descriptions from yet unexplored as well as previously explored regions across the Western Ghats, with an ever-increasing estimate of its known shrub frog diversity (Bossuyt, 2002;Kuramoto & Joshy, 2003;Biju & Bossuyt, 2005a, 2006Gururaja et al., 2007;Biju et al., 2010). The recognition of Raorchestes (Biju et al., 2010) provided further stability to the generic allocations of Asian shrub frogs, with frequent new discoveries holding up the genus as one of the most actively researched anuran groups of the Western Ghats during the following decade (Zachariah et al., , 2016Seshadri, Gururaja & Aravind, 2012;Padhye et al., 2013;Vijayakumar et al., 2014Vijayakumar et al., , 2016Priti et al., 2016;Gowande, Ganesh & Mirza, 2020). It is no surprise that since the turn of the century 43 new species have been formally described, resulting in a four-fold increase in the number of Raorchestes frogs known from this region within just two decades. ...
... Despite active research and frequent descriptions of new species, there has been a lack of integrative understanding of species in this large and rather morphologically conserved group of frogs ever-since the formal description of the genus. Although integrative approaches have increasingly been employed to delimit and describe new species during the past decade (e.g., Vijayakumar et al., 2014;Priti et al., 2016;Zachariah et al., 2016), such studies largely rely on older works based on genus Philautus (e.g., Bossuyt & Dubois, 2001;Biju & Bossuyt, 2009) for comparisons with previously known taxa. Vijayakumar et al. (2014Vijayakumar et al. ( , 2016 provided comprehensive phylogenies of Western Ghats Raorchestes frogs with lineage-based grouping of species; however, the diagnosis of these phylogenetically identified species assemblages based on morphological, acoustic, or behavioral characters remains unattempted. ...
... As taxonomic studies are increasingly becoming integrative in nature, call characters have gained importance in Indian anuran systematics (e.g., Kanamadi, Kadadevaru & Schneider, 2001;Kuramoto et al., 2007;Grosjean & Dubois, 2011;Bee, Suyesh & Biju, 2013a, 2013bGarg et al., , 2019. Specifically in the case of genus Raorchestes, out of the 55 species known from Peninsular India (prior to the present study), the call structure was previously known only for eleven species, namely Raorchestes (as Philautus) tuberohumerus, Raorchestes (as Philautus) luteolus, R. kakachi, R. graminirupes, R. flaviocularis, R. chalazodes, R. honnametti, R. kollimalai, R. sanctisilvaticus, R. silentvalley, and R. lechiya (Kuramoto & Joshy, 2001;Seshadri, Gururaja & Aravind, 2012;Bee, Suyesh & Biju, 2013b;Vijayakumar et al., 2014;Priti et al., 2016;Zachariah et al., 2016;Mirza et al., 2019;Gowande, Ganesh & Mirza, 2020). Due to lack of available acoustic data for a majority of Raorchestes species, vocalisation has not been effectively utilized for integrative systematic studies on this taxonomically challenging genus, and has become imperative for strengthening our understanding of systematic relationships particularly among several morphologically cryptic species. ...
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The genus Raorchestes is a large radiation of Old World tree frogs for which the Western Ghats in Peninsular India is the major center for origin and diversification. Extensive studies on this group during the past two decades have resolved long-standing taxonomic confusions and uncovered several new species, resulting in a four-fold increase in the number of known Raorchestes frogs from this region. Our ongoing research has revealed another five new species in the genus, formally described as Raorchestes drutaahu sp. nov., Raorchestes kakkayamensis sp. nov., Raorchestes keirasabinae sp. nov., Raorchestes sanjappai sp. nov., and Raorchestes vellikkannan sp. nov., all from the State of Kerala in southern Western Ghats. Based on new collections, we also provide insights on the taxonomic identity of three previously known taxa. Furthermore, since attempts for an up-to-date comprehensive study of this taxonomically challenging genus using multiple integrative taxonomic approaches have been lacking, here we review the systematic affinities of all known Raorchestes species and define 16 species groups based on evidence from multi-gene (2,327 bp) phylogenetic analyses, several morphological characters (including eye colouration and pattern), and acoustic parameters (temporal and spectral properties, as well as calling height). The results of our study present novel insights to facilitate a better working taxonomy for this rather speciose and morphologically conserved radiation of shrub frogs. This will further enable proper field identification, provide momentum for multi-disciplinary studies, as well as assist conservation of one of the most colourful and acoustically diverse frog groups of the Western Ghats biodiversity hotspot.
... A total of 53 Raorchestes species is known from the Western Ghats (Zachariah et al. 2016). Knowledge on biology of the Western Ghats amphibians is rather poor; particularly studies on reproductive behavior are missing for many species. ...
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The genus Raorchestes is characterized by direct development. Knowledge on biology of the Western Ghats amphibians is rather poor, particularly studies on reproductive behavior are missing for many species. Reliable records of direct development on land are available from species of the genus Raorchestes. We observed the egg development of endemic Nilgiri Bush Frog, Raorchestes tinniens in the Nilgiris. Our observation, showed that R. tinniens underwents direct development, and hatching of froglets occurred after 36 days. Based on our observation the eggs present in natural condition were easily affected or destroyed by many factors.
... ;Manamendra-Arachchi and Pethiyagoda, 2005;Meegaskumbura and Manamendra-Arachchi, 2005; Seshadri et al., 2012; Abraham et al., 2013 Abraham et al., , 2015Padhye et al., 2013;Wickramasinghe et al., 2013Wickramasinghe et al., , 2015Vijayakumar et al., 2014;Dehling et al., 2016;Zachariah et al., 2016). Additionally,Dubois et al. (2001) reported that NyctibatrachusBoulenger, 1882b (Nyctibatrachidae Blommers- Schlösser, 1993 possesses an MLP, but Radhakrishnan et al. (2007) clarified that no species of nyctibatrachid is known to possess this structure. ...
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Despite the impressive growth of knowledge on the phylogenetic systematics of dart-poison frogs and their relatives (Dendrobatoidea) over the past decade, many problems remain to be addressed. We analyzed up to 189 phenomic characters (morphology, behavior, defensive chemicals) and 15 mitochondrial and nuclear loci scored for 564 dendrobatoid and outgroup terminals, including 76 newly sequenced terminals and > 20 previously unanalyzed species, using tree-alignment and the parsimony optimality criterion in the program POY v.5.1.1 and additional analyses of the implied alignment using TNT v.1.5. Even though data coverage was highly heterogeneous, the strict consensus of 639 optimal trees is highly resolved and we detected only one instance of wildcard behavior involving a small clade of outgroup species. The monophyly of the median lingual process (MLP) possessing genus Anomaloglossus is decisively refuted, with the cis-Andean species being sister to Rheobates within Aromobatidae and the trans-Andean species nested within Hyloxalinae, implying two independent origins of the structure in Dendrobatoidea. Although this result was unexpected, it is not surprising given that the MLP evolved at least five times in Asian and African ranoids, including Arthroleptidae, Dicroglossidae, Mantellidae, and Rhacophoridae and either once in the most recent common ancestor of the massive clade Victoranura followed by independent losses or multiple times within component lineages. We restrict Anomaloglossus to the cis-Andean MLP-possessing species, describe a new genus for the trans-Andean MLP-possessing species, and resurrect Paruwrobates for its sister group, which includes Dendrobates andinus (formerly Ameerega), D. erythromos (formerly Hyloxalus and, until recently, Ameerega), and Prostherapis whymperi (formerly Hyloxalus). We also transfer Dendrobates maculatus from Ameerega to Epipedobates, making Ameerega an exclusively cis-Andean group. We describe two new species of the trans-Andean MLP-possessing genus-one from Cerro Tacarcuna, near the Colombo-Panamanian border, and the other from 800-900 m elevation on the western versant of the Colombian Cordillera Occidental (Cauca Department)-bringing the total number of species in the genus to seven. The discrete, round, white to yellowish-brown dots found on the venter of the new species from Cerro Tacarcuna and at least one other trans-Andean MLP-possessing species are formed by large, ellipsoid, densely distributed (up to 80 glands/mm²) granular glands. Although specimens of the new species from Cerro Tacarcuna exuded a noxious milky substance when handled, lipophilic alkaloids were not detected. In addition to the unexpected placement of the trans-Andean MLP-possessing species, major findings include the unexpected placement of Colostethus ruthveni and its undescribed sister species (the "C." ruthveni group) within Dendrobatinae as sister of the newly recognized tribe Dendrobatini (all dendrobatines except Phyllobates and the "C." ruthveni group). We describe a new genus for C. argyrogaster and C. fugax to remedy the paraphyly of Colostethus caused by the placement of those species as sister to Ameerega. Our evidence rejects the sister group relationship of Dendrobates + Oophaga in favor of Dendrobates + Adelphobates, which is consistent with their uniquely low diploid chromosome number of 2n = 18 (2n = 20 in Oophaga). With the exception of Anomaloglossus and Colostethus, all other genera are monophyletic. We recognize several monophyletic species groups-including the Atlantic Forest, trans-Andean, and 22-chromosome groups within Allobates, the An. stepheni, An. megacephalus, and An. beebei groups in Anomaloglossus, the C. latinasus (formed by the C. inguinalis and C. latinasus clades) and C. fraterdanieli groups within Colostethus, and the Am. braccata and Am. rubriventris groups within Ameerega-identify unambiguously optimized phenomic synapomorphies, and summarize patterns in the evolution of the diploid chromosome number, swelling of Finger IV in males, relative length of Fingers II and III, length of Finger V, and testicular and intestinal pigmentation. Finally, we address criticisms of the current taxonomy of Neotropical poison frogs and their relatives, concluding that they are either overstated, misguided, or false, and that the current system of names better communicates knowledge of the diversity of these frogs. Our results highlight the importance of increased taxon sampling, and we conclude by identifying key species to include in future phylogenetic analyses.
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The term “integrative taxonomy”, or the use of multiple lines of evidence in the delimitation and naming of new species, was independently introduced in two papers in 2005. This paper aims to provide a brief review of integrative taxonomy and the growth of molecular tools in systematics, with special reference to its prevalence and scope for biodiversity research in India. We review the literature to understand the state of progress in systematics from India since 2005 using both vertebrate and invertebrate examples. We end by summarising best practises and a workflow for integrative taxonomy, as well as emphasizing the need for a national strategy for taxonomy and systematic research with an outline on how to achieve this.
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A new cryptic species of the gekkonid genus Cnemaspis is described from the Central Western Ghats of Kerala, India. Cnemaspis palakkadensis sp. nov. is a small-sized (snout-vent length less than 35 mm) Cnemaspis in the littoralis clade. Although the new species superficially resembles C. littoralis, it shows moderate levels of genetic divergence in the 16S rRNA gene, and can be differentiated from all other Indian congeners by a suite of distinct morphological characters: dorsal scales homogenous, small, smooth; absence of conical or spine-like tubercles on flanks; ventral scales smooth, imbricate; dorsal scales of limbs smooth; 15 or 16 femoral pores on each side separated by 14 poreless scales; lamellae under fourth digit of manus 12-15 and pes 14-17; absence of whorls of pointed tubercles on tail; median subcaudals enlarged, imbricate, smooth. The species is found in an ignored low-lying forest habitat in parts of the Anakkal reserve forest in Kerala.
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Raorchestes is a speciose genus of bush frogs with high diversity occurring in the Western Ghats of In-dia. Relatively fewer species have been recorded across India, through Bangladesh, southern China, into Vietnam and Peninsular Malaysia. Many bush frogs are morphologically cryptic and therefore remain undescribed. Here, a new species, Raorchestes rezakhani sp. nov., is described from northeastern Bangla-desh based on morphological characters, genetics, and bioacoustics. The 16S rRNA gene distinguished this species from 48 known species of this genus. Bayesian Inference and Maximum Likelihood analyses indicated that the new species was most similar to R. tuberohumerus, a species found in the Western Ghats, and to R. gryllus, a species found in Vietnam. Bioacoustics indicated that their calls were similar in pattern to most Raorchestes species, although number of pulses, duration of pulses, pulse intervals and amplitude differentiated it from a few other species. It is suggested that northeastern India, Bangladesh, northern Myanmar, and southern China represent important, relatively unexplored areas that could yield additional species of Raorchestes. Since many remaining habitat patches in Bangladesh are under severe threat from deforestation, efforts should be made to protect these last patches from further degradation.
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A new rhacophorid frog is described from Eravikulam National Park in the Western Ghats of India. The species is morphologically dissimilar from any known member of this family in having a bright orange to reddish colouration, multiple macroglands on the body and extremely short limbs. Phylogenetic analyses of mitochondrial genes indicate that this new frog is nested in a radiation of shrubfrogs that had its origin on the Indian subcontinent, and which is here recognized as a distinct genus, Raorchestes gen. nov. The new species, Raorchestes resplendens sp. nov. is likely restricted to less than 3 sq. km on the summit of Anamudi, and deserves immediate conservation priority.
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Raorchestes flaviventris, a species of rhacophorid bush frog described from the Western Ghats by George Albert Boulenger in 1882, has never been reported from the region since its description. However, we herewith report a record of the species after almost 132 years and redescribe the species and also clarify confusions that prevailed over the taxonomic status of the species and its closely-related congeners, along with shedding light on literature regarding its distribution. Also, the recently described R. emeraldi Vijayakumar et al., 2014, which we suggest to be the same species, becomes a junior subjective synonym of R. flaviventris.
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Montane species distributions interrupted by valleys can lead to range fragmentation, differentiation and ultimately speciation. Paleoclimatic fluctuations may accentuate or reduce such diversification by temporally altering the extent of montane habitat and may affect species differentially. We examined how an entire montane bird community of the Western Ghats-a linear, coastal tropical mountain range-responds to topographic valleys that host different habitats. Using genetic data from 23 species (356 individuals) collected across nine locations, we examined if different species in the community reveal spatial concordance in population differentiation, and whether the timing of these divergences correlate with climatic events. Our results reveal a nested effect of valleys, with several species (10 of 23) demonstrating the oldest divergences associated with the widest and deepest valley in the mountain range, the Palghat Gap. Further, a subset of these 10 species revealed younger divergences across shallower, narrower valleys. We recovered discordant divergence times for all valley-affected montane birds, mostly in the Pleistocene, supporting the Pliestocene-pump hypotheses and highlighting the role of climatic fluctuations during this period in driving species evolution. A majority of species remain unaffected by valleys, perhaps owing to geneflow or extinction-recolonization dynamics. Studying almost the entire community allowed us to uncover a range of species' responses, including some generalizable and other unpredicted patterns. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
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Bush frogs of the genus Raorchestes are distributed mainly in the Western Ghats Escarpment of Peninsular India. The inventory of species in this genus is incomplete and there is ambiguity in the systematic status of species recognized by morphological criteria. To address the dual problem of taxon sampling and systematic uncertainty in bush frogs, we used a large-scale spatial sampling design, explicitly incorporating the geographic and ecological heterogeneity of the Western Ghats. We then used a hierarchical multi-criteria approach by combining mitochondrial phylogeny, genetic distance, geographic range, morphology and advertisement call to delimit bush frog lineages. Our analyses revealed the existence of a large number of new lineages with varying levels of genetic divergence. Here, we provide diagnoses and descriptions for nine lineages that exhibit divergence across multiple axes. The discovery of new lineages that exhibit high divergence across wide ranges of elevation and across the major massifs highlights the large gaps in historical sampling. These discoveries underscore the significance of addressing inadequate knowledge of species distribution, namely the "Wallacean shortfall", in addressing the problem of taxon sampling and unknown diversity in tropical hotspots. A biogeographically informed sampling and analytical approach was critical in detecting and delineating lineages in a consistent manner across the genus. Through increased taxon sampling, we were also able to discern a number of well-supported sub-clades that were either unresolved or absent in earlier phylogenetic reconstructions and identify a number of shallow divergent lineages which require further examination for assessment of their taxonomic status.
— We studied sequence variation in 16S rDNA in 204 individuals from 37 populations of the land snail Candidula unifasciata (Poiret 1801) across the core species range in France, Switzerland, and Germany. Phylogeographic, nested clade, and coalescence analyses were used to elucidate the species evolutionary history. The study revealed the presence of two major evolutionary lineages that evolved in separate refuges in southeast France as result of previous fragmentation during the Pleistocene. Applying a recent extension of the nested clade analysis (Templeton 2001), we inferred that range expansions along river valleys in independent corridors to the north led eventually to a secondary contact zone of the major clades around the Geneva Basin. There is evidence supporting the idea that the formation of the secondary contact zone and the colonization of Germany might be postglacial events. The phylogeographic history inferred for C. unifasciata differs from general biogeographic patterns of postglacial colonization previously identified for other taxa, and it might represent a common model for species with restricted dispersal.