Documenting the first ocurrence of Feihyla baladika (Anura, Rhacophoridae) in East Java: ecology, genetics, and habitat suitability
Previously, Feihyla baladika (Riyanto and Kurniati, 2014) was known exclusively from Sumatra, Indonesia. This study reports a new record of this species from the eastern region of Java Island, within a lowland tropical rainforest close to Pantai Kondang Merak. Due to the absence of other findings in...
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| author | Rijalullah, M. A. Khanifan, N. Assiddiqy, M. F. Soeprijadi, Anandhika M.S.P. Fathoni, M. Nurrofik, A. Kurniawan, N. Septiadi, L. |
| author_facet | Rijalullah, M. A. Khanifan, N. Assiddiqy, M. F. Soeprijadi, Anandhika M.S.P. Fathoni, M. Nurrofik, A. Kurniawan, N. Septiadi, L. |
| author_institution_txt_mv | [
{
"author": "M. A. Rijalullah",
"institution": "Department of Faculty of Sciences, Technology and Mathematics, Universitas Brawijaya, Malang, Indonesia"
},
{
"author": "N. Khanifan",
"institution": "Department of Faculty of Sciences, Technology and Mathematics, Universitas Brawijaya, Malang, Indonesia"
},
{
"author": "M. F. Assiddiqy",
"institution": "Department of Faculty of Sciences, Technology and Mathematics, Universitas Brawijaya, Malang, Indonesia"
},
{
"author": "Anandhika M.S.P. Soeprijadi",
"institution": "Independent Researcher, Madiun, East Java, Indonesia"
},
{
"author": "M. Fathoni",
"institution": "Manusela National Park, Ministry of Forestry - Republic of Indonesia"
},
{
"author": "A. Nurrofik",
"institution": "Department of Biology, Faculty of Mathematics and Natural Sciences, Universitas Brawijaya, Malang, Indonesia"
},
{
"author": "N. Kurniawan",
"institution": "deceased"
},
{
"author": "L. Septiadi",
"institution": "Wildlife Conservation Society – Indonesia Program, Bogor, Indonesia"
}
] |
| author_sort | Rijalullah, M. A. |
| baseUrl_str | https://ojs.akademperiodyka.org.ua/index.php/Zoodiversity/oai |
| collection | OJS |
| datestamp_date | 2026-07-06T23:39:50Z |
| description | Previously, Feihyla baladika (Riyanto and Kurniati, 2014) was known exclusively from Sumatra, Indonesia. This study reports a new record of this species from the eastern region of Java Island, within a lowland tropical rainforest close to Pantai Kondang Merak. Due to the absence of other findings in Java and some morphological differences along with a genetic distance of 2–3%, we cautiously refer to the specimens as F. cf. baladika. Species distribution modeling using MaxEnt suggests that F. baladika may potentially occur in Sumatra, Java, and Bali, in areas characterized by relatively low precipitation during the wettest month, forest cover, and low temperature seasonality. |
| doi_str_mv | 10.15407/zoo2026.03.225 |
| first_indexed | 2026-06-30T01:00:28Z |
| format | Article |
| fulltext |
DOI 10.15407/zoo2026.03.225
UDC 597.851:591.522:591.9(594.1/.2)
DOCUMENTING THE FIRST OCCURRENCE
OF FEIHYLA BALADIKA (ANURA, RHACOPORIDAE)
IN EAST JAVA: ECOLOGY, GENETICS,
AND HABITAT SUITABILITY
M. A. Rijalullah 1, N. Khanifan 1, M. F. Assiddiqy 1, Anandhika M.S.P. Soeprijadi 2,
M. Fathoni 3, A. Nurrofik 1, 4, N. Kurniawan 1 † & L. Septiadi 5
1 Department of Faculty of Sciences, Technology and Mathematics,
Universitas Brawijaya, Malang, East Java 65145, Indonesia
2 Independent Researcher, Madiun, East Java, Indonesia
3 Manusela National Park, Ministry of Forestry – Republic of Indonesia
4 SALAM (Sahabat Alam Indonesia), Malang, East Java, Indonesia
5 Wildlife Conservation Society — Indonesia Program,
Bogor, West Java 16128, Indonesia
* Corresponding author
E-mail: luhurseptiadi@gmail.com
M. A. Rijalullah (https://orcid.org/0000-0002-2136-2698)
N. Khanifan (https://orcid.org/0009-0008-9983-8036)
M. F. Assiddiqy (https://orcid.org/0000-0002-0155-9207)
M. Fathoni (https://orcid.org/0000-0001-6500-9995)
A. Nurrofik (https://orcid.org/0000-0002-1166-0667)
N. Kurniawan (https://orcid.org/0000-0001-7383-8742)
L. Septiadi (https://orcid.org/0000-0001-5195-5550)
urn:lsid:zoobank.org:pub:098B9857-DBA4-40E2-A385-F4F9AD358B61
Documenting the first ocurrence of Feihyla baladika (Anura, Rhacoporidae) in East
Java: ecology, genetics, and habitat suitability. Rijalullah, M. A., Khanifan, N., Assid-
diqy, M. F., Soeprijadi, Anandhika M.S.P., Fathoni, M., Nurrofik, A., Kurniawan, N. †
& Septiadi, L. — Previously, Feihyla baladika (Riyanto and Kurniati, 2014) was known ex-
clusively from Sumatra, Indonesia. This study reports a new record of this species from the
eastern region of Java Island, within a lowland tropical rainforest close to Kondang Merak
beach. Due to the absence of other findings in Java and some morphological differences
along with a genetic distance of 2–3%, we cautiously refer to the specimens as F. cf. baladika.
Fauna and Systematics Zoodiversity, 60(3): 225–244, 2026
© Publisher Publishing House “Akademperiodyka” of the NAS of Ukraine, 2026. The article is
published under an open access license CC BY-NC-ND (https://creativecommons.org/licenses/
by-nc-nd/4.0/)
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
M. A. Rijalullah, N. Khanifan, M. F. Assiddiqy, Anandhika M.S.P. Soeprijadi et al.
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
226
Species distribution modeling using MaxEnt suggests that F. baladika may potentially occur
in Sumatra, Java, and Bali, in areas characterized by relatively low precipitation during the
wettest month, forest cover, and low temperature seasonality.
Key words: Amphibian, Indonesia, phylogeny, species distribution model
Introduction
Old World tree frogs (Anura, Rhacoporidae) is one of the most diverse families of
amphibians in Asia (Chan et al., 2018), consisting of more than 400 species (Frost,
2024). The rapid and extensive diversification within the family, combined with a
lack of distinctive shared morphological characteristics, frequently led to misunder-
standing (e. g., Frost et al., 2006; Grosjean et al., 2008; Li et al., 2008; Biju et al., 2020;
Chan et al., 2020; Chen et al., 2020). One of its genera, Feihyla, is noted for having
the most diverse phylogenetic tree within the Rhacophoridae (Onn et al., 2018).
Based on previous phylogenetic studies (Biju et al., 2020; Liu et al., 2023), Feihyla
were clustered in to three groups: F. palpebralis group (2 members: F. palpebralis and
F. fuhua), F. vittiger group (3 members: F. inexpectata, F. kajau, and F. vittiger), and
F. vittatus group (5 members: F. vittatus, F. baladika, F. hansenae, F. senapatiensis,
F. shyamrupus, and F. wuguanfui).
Feihyla baladika (Riyanto and Kurniati, 2014) is currently known exclusively on
Sumatra Island (Riyanto and Kurniati, 2014; Biju et al., 2020) and no occurrences
have previously been recorded on other island that were part of Sundaland, such as
Java. This insular endemism has led to its classification as Near Threatened by the
International Union for the Conservation of Nature (IUCN SSC Amphibian Special-
ist Group, 2018). In addition, occurrence data is unavailable in Global Biodiversity
Information Facility (https://www.gbif.org) and limited to coordinates retrieved
from literatures (Riyanto and Kurniati, 2014; Biju et al., 2020). The lack of records
outside Sumatra has left its broader biogeographic pattern, habitat preferences, and
conservation status uncertain.
The limited documentation regarding the distribution of F. baladika could be
related to the rare encounter of this species during field surveys, due to challenges in
monitoring and a limited comprehension of their habitat preferences. Elith and Gra-
ham (2009) argue that this issue can be resolved by the utilisation of species distribu-
tion models (SDMs). Several previous research indicates that species distribution
models (SDMs) serve as valuable tools for exploring and predicting species distribu-
tion across various landscapes (e. g., Searcy & Shaffer, 2014; Fois et al., 2015; Kur-
niawan et al., 2024). MaxEnt (Kramer-Schadt et al., 2013) is a widely used SDM be-
cause it only requires presence data (Phillips et al., 2006), works well with small
sample sizes (Wisz et al., 2008), and suitable for rare and narrowly endemic species
(Rebelo and Jones, 2010; Rinnhofer et al., 2012).
In this study, we report the first confirmed occurrence of F. baladika in East Java
using an integrative approach. We employed molecular and morphological analyses
to verify species identity, assessed the ecological characteristics of the new locality,
and applied species distribution modeling (SDM) to estimate potential habitats
across Sumatra, Java, and Bali as a basis for future research. These islands, which
were included in the model due to their ecological suitability, are believed to be evo-
Documenting the First Occurrence of Feihyla Baladika (Anura, Rhacoporidae) in East Java
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
227
lutionarily connected and share biogeographic patterns among various taxa (Lohman
et al., 2011). Our findings aim to refine understanding of the species’ distributional
limits, guide conservation priorities, and highlight the need for intensified biodiver-
sity surveys in underexplored areas.
Material and Methods
Field Study and sampling
Field observation and sample collection were conducted in lowland forest near Kon-
dang Merak Beach, Malang Regency, and East Java Province, Indonesia during rainy
season (January–February 2024). Adult frogs, egg clutches, and habitat was photo-
graphed in the wild. The frog encounter’s location was documented using GPS
Garmin. Furthermore, detailed descriptions of the habitats were made, including the
recording of various abiotic factors such as microclimate (temperature and relative
humidity) and water (temperature, pH, dissolved oxygen, electric conductivity, total
dissolved solid, turbidity) parameters. Prior to euthanizing the frogs by immersing
them in a solution containing 0.5% tricaine methane sulfonate (MS-222), photo-
graphs were taken from different angles (dorsal, ventral, and lateral) of the frogs. Sub-
sequently, the liver tissue was stored in a microtube containing 96% ethanol for mo-
lecular study. Whole frog specimens were fixed overnight in 10% formalin, subse-
quently kept in 70% ethanol. Indonesia. Depositories: NK — Non-type were deposit-
ed in Laboratory of Animal Diversity and Environmental Technology, Biology De-
partment, Faculty of Sciences, Technology, and Mathematics, Brawijaya University,
Indonesia. Coordinate data from our field study were mapped using QGIS v.3.22.5.
Molecular data and Phylogenet ic analyses
Mitochondrial DNA was extracted from the liver tissue utilizing Quick-DNATM
Miniprep Plus kit following manufacturer’s protocol (Zymo Research Corporation).
DNA amplifications were performed using L1-L2 primer set (12S rRNA + tRNAval +
16S rRNA) (Table 1) following Zhang et al. (2013). The amplicons were evaluated
qualitatively using 2% agarose gel and quantitatively using NanoDrop 2000 spectro-
photometer.
DNA sequences were deposited in Genbank (PV820714-PV820716) and subse-
quently aligned using ClustalW in MEGA 7 with default parameters (Kumar et al.,
2016). Maximum Likelihood (ML) and Bayesian Interference (BI) were performed
on a sequence with total 328 base pair. The most suitable nucleotide substitution
model was determined using the Akaike Information Criterion (AIC) in jModelTest
Table 1 . Primer used for DNA amplification in this study
Primer name Sequence References
L2 LX12SN 5'-TACACACCGGCCGTCA-3' Kurniawan et al. (2023)
L2 LX16S1R 5'-GACCTGGATTACTCCGGTCTGAACTC-3' Kurniawan et al. (2023)
L1 16S2000H 5'-GTGATTAYGCTACCTTTGCACGGT-3' Kurniawan et al. (2023)
L1 12SAL 5'-AAACTGGGATTAGATACCCCACTAT-3' Kurniawan et al. (2023)
M. A. Rijalullah, N. Khanifan, M. F. Assiddiqy, Anandhika M.S.P. Soeprijadi et al.
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
228
(Posada, 2008). The General Time Reversible (GTR) model, with a proportion of
invariant sites (+I) and gamma-distributed rate variation among sites (+G), was
found to be the best fit nucleotide substitution model. Utilizing MrBayes software
(Ronquist & Huelsenbeck, 2003), uniform priors and four Metropolis-Coupled
Markov Chains Monte Carlo (MCMCMC) chains were used for 10 million genera-
tions of Bayesian analysis with tree sampling every 1000th generation. After discard-
ing the first 25% of trees as burn-in, Bayesian posterior probabilities for the clades
were summarized. Maximum Likelihood Clade Support (BS) was analysed using
10,000 comprehensive bootstrap replicates with the IQ-TREE web server (Trifinop-
oulos et al., 2016). Uncorrected pairwise genetic distances for the 16S rRNA were
computed in PAUP using all sites (Swofford, 2002). Phylogenetic trees were visual-
ized using FigTree v.1.3.1 (Rambaut, 2009).
Morphologica l Measurement and Analys is
The collected specimens undergo a total of 17 morphological character measure-
ments and a description of their webbing characteristics in order to compare them
with F. baladika from Sumatra in Riyanto & Kurniati (2014): SVL (snout-vent length),
HL (head length), HW (head width), ELW (width of upper eyelid), ED (eye diame-
ter), IND (internarial distance), IOD (interorbital distance), SNL (snout length), DNE
(distance from the nostril to the eye), TD (tympanum diameter), FLL (forelimb
length), HLT (hand length), THL (thigh length), TIL (tibia length), FL (proximal
edge of the inner metatarsal tubercle to the tip of the fourth toe), 3FDW (width of the
disk of the third finger), 4TDW (width of the disk of the fourth toe). The measure-
ment accuracy level is approximately 0.1 mm. Our morphometric analysis was con-
ducted by following the defensible framework by Chan and Grismer (2021). Meas-
ured data were pre-processed by applying allometric body size correction using the
GroupStruct r package to account for ontogenetic variation (Chan and Grismer, 2022).
Since the data did not follow normal distribution, the non-parametric Mann-Whit-
ney U test was employed. Nevertheless, Principal Component Analysis (PCA) was
still conducted to explore the data structure (Bispo & Marquez, 2023).
Species Distr ibut ion Model
We utilized Maximum Entropy (MaxEnt v.3.4.1) (Phillips et al., 2017) modeling for
predicting potential distribution of F. baladika. Total of five occurrence data of F.
baladika in Sumatera was obtained from literature (Riyanto & Kurniati, 2014; Biju et
al., 2020) and an occurrence of F. cf. baladika in Java was obtained from our field
study. The predictor variables were selected based on treefrog biology and ecology,
which modified from Kurniawan et al. (2024). A total of 23 variables were generated
using Google Earth Engine (https://code.earthengine.google.com) in 250x250 meter
scale for Sumatra–Java–Bali area, including 19 bioclimatic variables from World-
Clim v.2.1 (Fick and Hijmans, 2017), land cover from ESA WorldCover v.200 (Zan-
aga et al., 2022), tree cover from Hansen Global Forest Change v.1.10 (Hansen et al.,
2013), NDVI (MOD13Q1) from MODIS (Didan, 2021), and elevation from NASA
SRTM Digital Elevation 30m (Farr et al., 2007). All variables were resampled using r
package terra (Hijmans, 2025) to address discrepancies in raster extent. Subsequent-
ly, continuous-type variables (excluding land cover) were assessed for multicolline-
Documenting the First Occurrence of Feihyla Baladika (Anura, Rhacoporidae) in East Java
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
229
arity using Variance Inflation Factor (VIF) analysis in r package usdm (Naimi et al.,
2014). To develop the final species distribution model, two iterations were carried
out using identical parameter settings. The first aimed to eliminate variables with
zero contribution, while the second finalized the model based on the remaining pre-
dictors. Parameter were used in this study including: a subsample approach with
20% random test points, 1.5 regularization multiplier, 10 replicates, linear feature (L)
only, 5000 maximum iteration, and other parameters were setting in default. Jack-
knife analysis was performed to evaluate predictor variables contribution in our
model. The fitness of our model was evaluated based on area under the curve value
(AUC) which depicted in receiver operating characteristic (ROC) curve. Our mod-
elled species distribution map was visualized using QGIS v.3.22.5. We also utilized
Geospatial Conservation Assessment Tool (GeoCAT) (http://www.kew.org) to eval-
uate the possible IUCN conservation status based on area of occupancy (AOO) and
extent of occurrence (EOO) (4 km2 cell size).
Results
Feihyla cf. baladika
Non-type. Indonesia: East Java Province: Malang Regency, Bantur District, lowland forest near Kon-
dang Merak Beach [8°23'31.43" S 112°31'4.58" E], 20 m a. s. l., secondary lowland forest, temporary pond
near vehicle road, 17.01.2024, 5 {, 3 } (M. A. Rijalullah & M. F. Assiddiqy) (NK).
Identif icat ion. The collected specimens are morphologically aligned with the
Feihyla vittatus group (also referred to as the Rohanixalus group by Biju et al., 2020),
based on the following characteristics: (1) the presence of dorsolateral stripes — spe-
cifically, a pair of contrasting light-colored stripes that originate at the tip of the
snout (with a darker line underneath), run over the upper eyelid margins, and termi-
nate near the vent on both sides. This pattern differs from that of the Feihyla palpe-
bralis group, which has a white streak along the upper lip margin extending from the
snout tip or below the eye to the shoulder, and from the Feihyla vittiger group, which
exhibits a narrow white streak starting from the snout tip and extending along the
lateral surfaces of the head to the groin (without the darker line underneath), clearly
separating the dorsal and lateral coloration; and (2) nest type — F. vittatus forms
bubble-nests, in contrast to the jelly-nests observed in both the F. palpebralis and
F. vittiger groups.
F. baladika is known only from North Sumatra and West Sumatra (Riyanto
& Kurniati, 2014; Biju et al., 2020). It differs genetically from other closest con-
geners: F. hansenae from Thailand, Cambodia and Myanmar (Yodthong et al.,
2014); F. senapatiensis from India (Manipur, Nagaland, Mizoram and Tripura)
(Biju et al., 2020); F. shyamrupus from India (Arunachal Pradesh and Nagaland)
and new record from China (southern Xizang) (Biju et al., 2020; Liu et al., 2023);
F. wuguanfui from China (Cangyuan County, Lincang City, Jiangcheng County,
Pu’er City and Ximeng County in southern Yunnan), western Myanmar and
northern Laos (Liu et al., 2023); and F. vittatus from India, Bangladesh, Myan-
mar, Thailand, Laos, Cambodia, Vietnam and southern China (Aowphol et al.,
2013; Biju et al., 2020).
M. A. Rijalullah, N. Khanifan, M. F. Assiddiqy, Anandhika M.S.P. Soeprijadi et al.
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
230
Morphological characters of these specimens (n = 8; NK 2164–67, NK 2170–73)
differ with other Feihyla, which includes: (1) lack of dark stripes on dorsum (vs.
present in F. shyamrupus, and F. vittatus), (2) distinct tympanum (vs. indistinct in
F. marginis, F. punctatus and some specimen of F. vittatus), (3) finger free of web (vs.
present rudimentary in F. shyamrupus, F. vittatus, F. punctatus, F. palpebralis and
F. marginis), (4) dorsal skin smooth (vs. dorsal skin sparsely granular in F. vittatus,
Fig. 1. Phylogenetic tree of Bayesian Inference and Maximum Likelihood analysis based on 328 bp of 16S
rRNA of F. cf. baladika from East Java and other related species. Numbers on the branches represent the
nodal supports for Maximum Likelihood Bootstrap (top) and Bayesian Posterior Probabilities (bottom)
Table 2 . Uncorrected pairwise sequence divergence among
F. baladika 16S ribosomal RNA sequences of mtDNA
No Taxa 1 2 3 4 5 6 7
1 PV820714 (NK 2164) F. cf. baladika East Java
2 PV820714 (NK 2165) F. cf. baladika East Java 0.00
3 PV820714 (NK 2168) F. cf. baladika East Java 0.00 0.00
4 MW054235 F. baladika Sumatera 0.03 0.03 0.03
5 MW054232 F. baladika Sumatera 0.03 0.03 0.03 0.00
6 MW054233 F. baladika Sumatera 0.03 0.03 0.03 0.00 0.00
7 MW054234 F. baladika Sumatera 0.02 0.02 0.02 0.01 0.00 0.01
Documenting the First Occurrence of Feihyla Baladika (Anura, Rhacoporidae) in East Java
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
231
F. nauli, F. fuhua, F. inexpectata, F. kajau, F. palpebralis and F. vittiger), (5) contrasting
light coloured dorsolateral stripes (vs. absent in F. palpebralis, F. fuhua, F. inexpecta-
ta, F. kajau and F. vittiger).
Based on morphological characters and geographic distribution, our specimen
closely related with F. baladika. However, several morphological characters in our
specimen exhibit slight differences when compared to F. baladika (characters in pa-
rentheses) described by Riyanto & Kurniati (2014), including: (1) foot webbing
moderate, webbing up to the first to second subarticular tubercle on either side of toe
IV (vs. webbing up to the second subarticular tubercle on either side of toe IV); (2)
prominent white spots around the cloaca (vs. not explained).
Phylogeny and genetic distance. Aligned sequence matrix of 16S rRNA
(328 bp) comprises of 129 parsimony-informative, 155 variable sites, 26 singleton
sites, and 173 conserved sites. Phylogenetic trees of both ML and BI demonstrated
identical topologies and well-supported nodes and suggested these specimens were
nested in the genus Feihyla and separated from Sumatran F. baladika lineage
(MLBS = 99, BI = 1) (Fig. 1). The uncorrected p-distance of the 16s rRNA between
F. baladika from Sumatra and East Java ranged 2–3% (Table 2). Therefore, we cau-
tiously confer that these newly collected specimens are F. cf. baladika.
Description. Specimens (n = 8; NK 2164–67 and NK 2170–73) (Fig. 2) have a
slender body and small sized adults ({ SVL 23.3–24.8 mm, } SVL 25.2–26.2 mm).
Fig. 2. Freshly preserved adult specimens (NK 2164 ({), NK 2165 (})) from lowland forest near
Kondang Merak Beach, Malang, East Java, Indonesia a — dorsal ({); b — ventral ({); c — ventral
left hand ({); d— ventral left foot ({) of NK 2164. Sexual dimorphism could be distinguished by
lateral yellow line prominence in adult (e) } and (f) {. Scale bars 5 mm. Photos by M. F. Assiddiqy
and A. M. S. P. Soeprijadi
cа e
White spots
b d f
M. A. Rijalullah, N. Khanifan, M. F. Assiddiqy, Anandhika M.S.P. Soeprijadi et al.
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
232
Head wider than long (HL/HW =
0.77–0.96); snout pointed and elongat-
ed (SL/HL = 0.43–0.60); nostril ovoid
and closer to tip of snout than eye; can-
thus rostralis rounded, distinct; loreal
region concave; interorbital space con-
cave, narrower to broader than upper
eyelid (IOD/ELW = 0.85–1.71), and
exceeds internarial distance (IND/
IOD = 0.72–0.96); eye large (ED/HL =
0.43–0.48), eye diameter similar to
snout length (ED/SL = 0.77–1.03), pu-
pil horizontally elongated to rounded;
tympanum distinct, rounded, smaller
than eye diameter (TD/ED = 0.23–0.4).
Single median vocal sac; tongue at-
tached anteriorly, deeply notched pos-
teriorly with prominent U-shaped.
Forelimbs slender (FLL/SVL = 0.37–0.52); fingers free of web, relative length
I < II < IV < III, well-developed disks on tip; third disk width approximately equal to
tympanum width (3FDW/TD = 0.5–1.86); subarticular tubercles well developed,
oval; inner surface nuptial pad at the base of first finger present.
Hindlimbs slender, tibia averaging slightly less than to over half snout-vent
length (TIL/SVL = 0.41–0.59), thigh length approximately equal to tibia length
(THL/TIL = 0.76–1.19); toes webbed moderately with varying formula (Table 4),
relative length I < II < III < V < IV; developed disks on tip of toes, smaller to broader
than finger (4TDW/3FDW = 0.38–1.50); subarticular tubercles well developed, oval;
inner metatarsal tubercle distinct; outer metatarsal tubercle absent.
Skin texture on dorsal surface smooth; ventral surface smooth, thighs and belly
surface composed of granules.
Coloration in life; Dorsal surface varies from creamy, pale brown to reddish
brown with blotches ranging from faint dark to darker brown, some blotches slight-
ly clumped; yellow lateral line runs from the tip of the snout to vent, tiny black
speckles start at the loreal region and extends to dorsoventral; belly and ventral
head are white, with yellowish coloration on the tip of the snout, tiny black speckles
present on hindlimbs (thigh to toes) and forelimbs (palm), prominent white spots
on vent; pupil dark, iris gold.
Coloration in preservation; Dorsal surface light to darker brown, finger I and II
lighter than III and IV; light yellow lateral line running from tip of snout to vent, tiny
black speckles present on dorsoventral and loreal region, white blotch in the middle
of dorsoventral; ventral surface white, white spots on vent absent; pupil dark; iris
yellow to gold.
Morphometric analysis and variat ions. According to our PCA analysis
(Fig. 3) (n = 10; see Appendix Table A1, Table 4), PC1 had the eigenvalue of 9.76 indicat-
ing that most variation (57%) is contributed by the X-axis (PC1). Along the PC1, F. cf.
baladika from East Java is separated from Sumatran F. baladika. The Y-axis (PC2) had the
Fig. 3. Plot of two principal components of F. cf. baladi-
ka from East Java and F. baladika from Sumatra, using
17 allometric body-size correction characters
Documenting the First Occurrence of Feihyla Baladika (Anura, Rhacoporidae) in East Java
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
233
Table 3 . Morphometric comparison of F. cf. baladika
from East Java and F. baladika from Sumatra
Character Population
East Java (this study) Sumatra(Riyanto & Kurniati, 2014)
Sexes { (n = 5) ♀ (n =3) { (n = 5)
SVL 24.0 ± 0.7 (23.3–24.8) 25.8 ± 0.5 (25.2–26.2) 21.4 ± 0.3 (21.1–21.8)
HL 6.8 ± 0.2 (6.5–7) 7.0 ± 0.0 (7.0) 7.9 ± 0.3 (7.4–8.2)
HW 7.5 ± 0.1 (7.4–7.6) 8.3 ± 0.1 (8. 2–8.4) 7.4 ± 0.3 (7.1–7.8)
ELW 2.2 ± 0.4 (1.7–2.6) 1.9 ± 0.1 (1.8–1.9) 1.0 ± 0.1 (0.9–1.1)
ED 3.0 ± 0.0 (3.0) 3.1 ± 0.1 (3.0–3.1) 3.4 ± 0.2 (3.1–3.6)
IND 2.2 ± 0.1 (2.1–2.3) 2.2 ± 0.0 (2.2) 2.2 ± 0.1 (2.1–2.4)
IOD 2.5 ± 0.2 (2.2–2.7) 2.9 ± 0.1 (2.8–2.9) 2.7 ± 0.2 (2.4–3)
SNL 3.2 ± 0.1 (3.0–3.4) 3.7 ± 0.2 (3.5–3.9) 3.7 ± 0.2 (3.5–4)
DNE 1.7 ± 0.2 (1.5–1.9) 1.9 ± 0.2 (1.7–2.1) 1.9 ± 0.2 (1.6–2)
TD 0.9 ± 0.2 (0.7–1.2) 0.9 ± 0.2 (0.8–1.2) 1.1 ± 0.1 (1–1.2)
FLL 10.3 ± 0.5 (9.7–10.8) 11.5 ± 0.7 (10.7–12) 9.7 ± 0.3 (9.4–10.1)
HLT 7.2 ± 1.1 (5.6–8.3) 8.4 ± 0.3 (8.2–8.8) 6.8 ± 0.3 (6.3–7.1)
THL 11.2 ± 0.6 (10.5–11.7) 12.7 ± 0.2 (12.6–12.9) 10.2 ± 0.6 (9.8–11.2)
TIL 11.8 ± 0.7 (10.8–12.4) 13.4 ± 0.6 (12.8–13.8) 10.7 ± 0.5 (10.2–11.3)
FL 9.8 ± 0.5 (9.1–10.4) 10.7 ± 1.0 (9.8–11.8) 9.4 ± 0.3 (9–9.8)
3FDW 0.7 ± 0.1 (0.6–0.9) 1.0 ± 0.3 (0.7–1.3) 1.4 ± 0.2 (1.2–1.6)
4TDW 0.6 ± 0.1 (0.5–0.7) 0.8 ± 0.1 (0.8–0.9) 1.1 ± 0.1 (0.9–1.3 )
Note . See Material and Methods for abbreviations.
Table 4. Toe webbing variations of F. cf. baladika
from East Java between sexes
Voucher ID Sex Toe Webbing Formula
NK 2164 { I 1–2 II 1–2 III 1–2 IV 1–1 V
NK 2167 I 1–2 II 1–2 III 1–2 IV 1 - 1 V
NK 2171 I 1–2 II 1–2 III 1–2 IV 2 - 1 V
NK 2172 I 1–2 II 1–2 III 1–2 IV 2 - 1 V
NK 2173 I 1–1 ½ II 1–2 III 1–2 IV 1–1 V
NK 2165 } I 1–1 ½II 1–2 III 1–2 IV 1–1 V
NK 2166 I 1–1 ½II 1–2 III 1–2 IV 1–1 V
NK 2170 I 1–2 II 1–2 III 1–2 IV 2–1 V
eigenvalue of 2.83 indicating that the variation (17%) also contributed to further separate
F. cf. baladika and F. baladika. PCA loading for PC1 ranged from –0.30 to 0.31 with heav-
ier loading on ELW (0.31), SVL (0.30), and FLL (0.29). The Mann–Whitney U test
showed that the F. cf. baladika and F. baladika are significantly different (p < 0.05) in 10
assessed characters: SVL, HL, ELW, ED, SNL, FLL, THL, TIL, 3FDW, and 4TDW.
Sexual dimorphism (Table 3) is observed in seven morphometric characters of
adults { (n = 5) and } (n = 3). SVL in adults { (Mean ± SD = 24.0 ± 0.7) is shorter
than in adults } (25.8 ± 0.5), HW in adults { (7.5 ± 0.1) is shorter than in adults
M. A. Rijalullah, N. Khanifan, M. F. Assiddiqy, Anandhika M.S.P. Soeprijadi et al.
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Fig. 4. The 24-hours microclimatic fluctuation (temperature and relative humidity) at encoun-
tered breeding site of F. cf. baladika from East Java
Fig. 5. Documentation of F. cf. baladika (NK 2164 ({), NK 2165 (})) from lowland forest area near Kon-
dang Merak beach, Malang, East Java, Indonesia: a — breeding site view from paved road with dashed line
rectangle indicating the habitat site; b — paved road view from breeding site; c— pond in dry condition,
with dashed lined circle indicating the position of the frog: d — amplecting pairs, e — oviposition, and f —
bubble nest filled with egg of F. cf. baladika. Photographed by M. A. Rijalullah and A. M. S. P. Soeprijadi
а
b
d
e
f
c
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} (8.3 ± 0.1), IOD in adults { (2.5 ± 0.2) is shorter than in adults } (2.9 ± 0.1), SNL
in adults { (3.2 ± 0.1) is shorter than in adults } (3.7 ± 0.2), THL in adults { (11.2 ±
0.6) is shorter than in adults } (12.7 ± 0.2), TIL in adults { (11.8 ± 0.7) is shorter
than in adults } (13.4 ± 0.6), 4TDW in adults { (0.6 ± 0.1) is shorter than in adults
} (0.8 ± 0.1). Based on toe webbing formula examination (Table 4), most { have toe
II webbing that is II 1–2 III, while most } have toe II webbing that is II 1½–2 III,
indicating a tendency regarding sexual dimorphism. However, this characteristic is
not definite sexual dimorphism diagnostic, as evidenced by the exceptions in NK
2173 ({) and NK 2170 (}), Table 4.
Habitat and natural histor y. The first two individuals found were a pair
that was spawning ({: NK 2164, }: NK 2165) and followed by oviposition by the }
(NK 2165) who was seen laying her bubble nest in the foliage overhanging the tem-
porary pond (abiotic parameters of pond water can be seen in Table 5) surrounded
by dense vegetation and close to the paved road (Fig. 4). The discovery occurred at
night at 8.45 pm, during the rainy season. Temperature and relative humidity meas-
urements recorded 24 hours after the discovery showed a temperature range of 24.6–
29.9 ºC (Mean ± SD = 26.4 ± 1.8) and relative humidity of 77.4–90.4% (86.1± 4.2)
(Fig. 5). Other anuran species found in the same habitat included Rhacophorus rein-
wardtii, Microhyla palmipes, and Hylarana chalconota.
Distr ibution. F. baladika is distributed in lowland area within 15–273 m
a.s.l. in Sumatra and Java (Fig. 6). This species is currently known from the fol-
lowing areas:
• North Sumatra: Tapanuli (Biju et al., 2020: MZB Amph 23920, 23951) and
Berastagi, Karo (Biju et al., 2020: MZB Amph 31928).
• West Sumatra: Solok Selatan (Riyanto & Kurniati, 2014: MZB Amph 17935–
17939).
• Bengkulu: Rejang Lebong (Biju et al., 2020: MZB Amph 26114).
• East Java: Malang (this study: NK 2164–2167 and NK 2170–2173).
Based on the current known distribution data, the extent of occurrence (EOO) of
F. baladika is estimated 28,186,778.3 ha, while the area of occupancy (AOO) is 2,400 ha.
Species distr ibution model using MaxEnt. Our species distribution
model for Feihyla baladika resulted an acceptable performance (AUC = 0.801)
(Fig. 7). The most influential predictor variables (Fig. 8) were precipitation of the
wettest month (Bio13, 81.2%), land cover (8.4%), and temperature seasonality
(Bio04, 4.8%). According to the model, suitable habitats for F. baladika are charac-
Table 5 . Microclimatic parameters measured at temporary pond
at encountered breeding site of F. cf. baladika from East Java
Parameter Mean (Range)
Temperature (°C) 27.0 (26.8–27.1)
pH 6.8 (6.7–6.8)
TDS (ppm) 324.8 (317–330)
EC (µS) 650 (434–660)
DO (mg/L) 2.4 (2.3–2.5)
Turbidity (NTU) 30 (29.5–30.8)
M. A. Rijalullah, N. Khanifan, M. F. Assiddiqy, Anandhika M.S.P. Soeprijadi et al.
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Fig. 6. Geographic distribution of F. baladika and F. cf. baladika (this study) in Sumatra, Java and
Bali. Distribution probability was established using Maximum Entropy modeling
Fig. 7. Receiver Operating Characteristic (ROC) curve based on Maximum Entropy modeling
for F. baladika
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237
terized by precipitation of 145–233 mm during the wettest month, areas with tree
cover, and low temperature seasonality.
Discussion
Our findings from East Java contribute valuable data regarding the current distribution,
habitat, and morphological characteristics of F. cf. baladika. Morphological analysis re-
vealed that the population from East Java exhibits significant differences from the F. bala-
dika specimens originating from Sumatra, with 10 morphometric characters depicting
significant differences. In comparison with other congener cryptic species (F. hansenae
vs. F. cf. hansenae = 5.2–5.7%, F. shyamrupus vs. F. cf. shyamrupus = 2.8%) (Biju et al.,
2020), genetic distance analysis (ranging from 2–3%) supports the possibility that Javan
F. cf. baladika may represent a cryptic species from Sumatran F. baladika. However, given
the lack of comparative data from the central to western regions of Java Island, this justi-
fication should be interpreted with caution. In addition, we are also unable to compare
our female specimen with Sumatran F. baladika due to the absence of sample (Riyanto &
Kurniati, 2014; Biju et al., 2020). Therefore, further specimens from central and western
Java, as well as female samples of F. baladika from Sumatra, are essential to conclusively
assess the taxonomic status of F. cf. baladika.
The distribution, ecology, and systematics of F. baladika populations remain poorly
understood outside of Sumatra. In Java, the species has only been recorded at our study
site in East Java, although the taxonomic status of this population remains uncertain and
is therefore referred to as F. cf. baladika. Our species distribution model suggests that F.
baladika may also occur in other forested areas characterized by low precipitation and
minimal temperature fluctuation. Among the environmental predictors, precipitation
(Bio13) was the most influential variable, accounting for 81.2% of the model’s contribu-
tion. This result aligns with regional climatic data from Avia (2019), which reported that
East Java receives less rainfall than the western and central regions of the island during
the rainy season. Supporting this hypothesis, a recent observation of F. baladika at the
Way Canguk Research Station in Lampung, Sumatra (Septiadi, pers. comm., 2025), also
Fig. 8. Environmental variables contribution based on Maximum Entropy modeling
for F. baladika
M. A. Rijalullah, N. Khanifan, M. F. Assiddiqy, Anandhika M.S.P. Soeprijadi et al.
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
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indicates the species’ preference for areas with relatively low precipitation. Such environ-
mental variation may be a key factor limiting the species’ occurrence in the wetter west-
ern and central parts of Java. However, further field surveys in those regions are neces-
sary to validate our model predictions.
The habitat occupied by F. cf. baladika in East Java appears similar to that of F. bala-
dika in Sumatra, as both are found in disturbed lowland forests affected by anthropogen-
ic activities, such as vehicle-accessible forest roads in East Java and palm oil monocul-
tures in Sumatra (IUCN SSC Amphibian Specialist Group, 2018). These habitat condi-
tions (Figure 4) underscore the need to initiate in-situ conservation efforts. Although F.
cf. baladika exhibits ecological traits similar to F. baladika, including tolerance of dis-
turbed habitats and association with temporary ponds (Riyanto & Kurniati, 2014; Frost
et al., 2015; Biju et al., 2020), the sustainability of its habitat near Kondang Merak Beach
in East Java remains a concern. Targeted measures, such as improved waste management
to reduce water pollution and further surveys to explore the feasibility of artificial ponds,
are recommended. This urgency is further supported by the dense vegetation surround-
ing the temporary ponds, which also serve as important breeding sites for other rhacoph-
orids, including Polypedates pseudotilophus, P. leucomystax, and Rhacophorus reinwardtii
(Kadafi et al., 2019; Kurniawan et al., 2023; Kurniawan et al., 2024).
The disjunct distribution of F. baladika highlights the importance of refined assess-
ments of species range and conservation status. Although the extent of occurrence (EOO)
may suggest a broader distribution consistent with a Least Concern (LC) classification
under IUCN criteria, the area of occupancy (AOO) may place the species closer to the
threshold for Endangered (EN) status. Recent records of Polypedates pseudotilophus
(Kurniawan et al., 2023) and Nyctixalus margaritifer (Hanifa et al., 2023) from East Java,
both previously unrecorded in this region, suggest that amphibian diversity in East Java
has been historically underestimated. Furthermore, the deforestation that has occurred
on this island since the 1950s (Haryadi and Andarwati, 2019), which currently makes
East Java the region with the highest deforestation rate on the island of Java (Prasetyo et
al., 2009), deserves concern. These findings highlight the urgent need for intensive and
long-term monitoring in East Java to inform more accurate conservation assessments
and support the preservation of enigmatic biodiversity.
Acknowledgement. We are grateful to Andik Syaifuddin (Sahabat Alam Indo-
nesia) and Abdul Mutholib Shahroni (Universitas Brawijaya) for assisting in field
sampling. We also thank Ari Ardiantoro (Universitas Brawijaya) and Kartika Praba-
sari (Universitas Tanjungpura) for their support in molecular data analysis.
REFERENCES
Aowphol, A., Rujirawan A., Taksintum W., Arsirapot S. & McLeod, D. S. 2013. Re-evaluating
the taxonomic status of Chiromantis in Thailand using multiple lines of evidence
(Amphibia: Anura: Rhacophoridae). Zootaxa, 3702 (2), 101–123. https://doi.org/10.11646/
zootaxa.3702.2.1
Biju, S. D., Garg, S., Gokulakrishnan, G., Chandrakasan, S., Thammachoti, P., Ren, J., Gopika, C.,
Bisht, K., Hamidy, A. & Shouche, Y. 2020. New insights on the systematics and reproductive
behaviour in tree frogs of the genus Feihyla, with description of a new related genus from Asia
(Anura, Rhacophoridae). Zootaxa, 4878 (1), 1–55. https://doi.org/10.11646/zootaxa.4878.1.1
Documenting the First Occurrence of Feihyla Baladika (Anura, Rhacoporidae) in East Java
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
239
Bispo, R. & Marques, F. 2023. Stability of principal components under normal and non-nor-
mal parent populations and different covariance structures scenarios. Journal of Statistical
Computation and Simulation, 93 (7), 1060–1076. https://doi.org/10.1080/00949655.2022.
2125971
Chan, K. O. & Grismer, L. L. 2022. GroupStruct: An R Package for Allometric Size Correction.
Zootaxa, 5124 (4), 471-482. https://doi.org/10.11646/zootaxa.5124.4.4
Chan, K. O., Grismer, L. L., Brown, R. M. 2018. Comprehensive multi-locus phylogeny of Old
World tree frogs (Anura, Rhacophoridae) reveals taxonomic uncertainties and potential
cases of over- and underesti-mation of species diversity. Molecular Phylogenetics and Evo-
lution, 127, 1010–1019. https://doi.org/10.1016/j.ympev.2018.07.005
Chan, K. O., Hutter, C.R., Wood, Jr. P. L., Grismer, L. L. & Brown, R. M. 2020. Target-cap-
ture phylogenomics provide insights on gene and species tree discordances in Old World
treefrogs (Anura: Rhacophoridae). Proceedings of The Royal Society, 287 (1940), 1–9. https://
doi.org/10.1098/rspb.2020.2102
Chen, J. M., Prendini, E., Wu, Y. H., Zhang, B. L., Suwannapoom, C., Chen, H. M., Jin, J. Q.,
Lemmon, E. M., Lemmon, A. R., Stuart, B. L., Raxworthy, C. J., Murphy, R. W., Yuan, Z. Y.
& Che, J. 2020. An integrative phylogenomic approach illuminates the evolutionary history
of Old World tree frogs (Anura: Rhacophoridae). Molecular Phylogenetics and Evolution,
145, 106724. https://doi.org/10.1016/j.ympev.2019.106724
Didan, K. (2021). MODIS/Terra Vegetation Indices 16-Day L3 Global 250m SIN Grid V061
[Data set]. NASA EOSDIS Land Processes Distributed Active Archive Center. https://doi.
org/10.5067/MODIS/MOD13Q1.061. Accessed on 15 June 2025.
Elith, J. & Graham, C. H. 2009. Do they? How do they? Why do they differ? On finding reasons
for differing performances of species distribution models. Ecography, 32, 66–77. https://
doi.org/10.1111/j.1600-0587.2008.05505.x
Farr, T. G., Rosen, P. A., Caro, E., Crippen, R., Duren, R., Hensley, S., Kobrick, M., Paller, M.,
Rodriguez, E., Roth, L., Seal, D., Shaffer, S., Shimada, J., Umland, J., Werner, M., Oskin, M.,
Burbank, D. & Alsdorf, D. E. 2007. The Shuttle Radar Topography Mission. Reviews of Geo-
physics, 45 (2). https://doi.org/10.1029/2005RG000183
Fick, S. E. & Hijmans, R. J. 2017. WorldClim 2: new 1km spatial resolution climate surfaces
for global land areas. International Journal of Climatology, 37 (12), 4302-4315. https://doi.
org/10.1002/joc.5086
Fois, M., Fenu, G., Cuena Lombraña, A., Cogoni, D. & Bacchetta, G. 2015. A practical method to
speed up the discovery of unknown populations using species distribution models. Journal
for Nature Conservation, 24, 42–48. https://doi.org/10.1016/j.jnc.2015.02.001
Frost, D. R. 2015. Amphibian Species of the World: an Online Reference. Version 6.0 (14 Janu-
ary 2016). New York, USA. Available at: http://research.amnh.org/herpetology/amphibia/
index.html. Accessed on 31 May 2025.
Frost, D. R. 2024. Amphibian Species of the World, an Online Reference. Version 6.2. Electronic
Database. American Museum of Natural History, New York. https://amphibiansofthe-
world.amnh.org/. Accessed on 31 May 2025.
Frost, D. R., Grant, T., Faivovich, J. N., Bain, R. H., Haas, A., Haddad, C. F. B., De Sá, R., Chan-
ning, A., Wilkinson, M., Donnellan, S. C., Raxworthy, C. J., Camp-bell, J. A., Blotto, B. L.,
Moler, P., Drewes, R. C., Nussbaum, R. A., Lynch, J. D., Green, D. M. & Wheler, R. C. 2006.
The amphibian tree of life. Bulletin of the American Museum of Natural History, 2006 (297),
1–291. https://doi.org/10.1206/0003-0090(2006)297[0001:TATOL]2.0.CO;2
Grosjean, S., Delorme, M., Dubois, A. & Ohler, A. 2008. Evolution of reproduction in the Rhaco-
phoridae (Amphibia, Anura). Journal of Zoological Systematics and Evolutionary Research,
46 (2), 169–176. https://doi.org/10.1111/j.1439-0469.2007.00451.x
Hanifa, B. F., Septiadi, L., Hasyim, M. A., Fathoni, M., Prabasari, K., Erfanda, M. P., Rahmad
ana, M., Widjanarko, H. & Kurniawan, N. 2023. New data on and the easternmost record
M. A. Rijalullah, N. Khanifan, M. F. Assiddiqy, Anandhika M.S.P. Soeprijadi et al.
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
240
of the Javan endemic Pearly Tree Frog, Nyctixalus margaritifer Boulenger, 1882 (Anura,
Rhacophoridae). Check List, 19 (6), 971–982. https://doi.org/10.15560/19.6.971
Hansen, M. C., Potapov, P. V., Moore, R., Hancher, M., Turubanova, S. A., Tyukavina, A., Thau, D.,
Stehman, S. V., Goetz, S. J., Loveland, T. R., Kommareddy, A., Egorov, A., Chini, L., Jus-
tice, C. O. & Townshend, J. R. G. 2013. High-Resolution Global Maps of 21st-Century For-
est Cover Change. Science, 342 (6160), 850–853. http://dx.doi.org/10.1126/science.1244693.
Data available on-line from: https://glad.earthengine.app/view/global-forest-change.
Haryadi, F. T., Andarwati, S. 2019. The roles of religion in participatory development communi-
cation in the environmental issues in Indonesia. J Agric Environ Int Dev (JAEID), 113 (2),
171–180. https://doi.org/10.12895/jaeid.20192.887
Hijmans, R. 2025. terra: Spatial Data Analysis. R package version 1.8-29. https://CRAN.R-proj-
ect.org/package=terra. Accessed on 15 June 2025.
IUCN SSC Amphibian Specialist Group. 2018. Chiromantis baladika. The IUCN Red List of
Threatened Species 2018: e.T89187134A95509827. https://dx.doi.org/10.2305/IUCN.
UK.2018-1.RLTS.T89187134A95509827.en. Accessed on 06 June 2025.
Kadafi, A. M., Fathoni, M., Fauzi, M. A., Firmansyah, R., Priambodo, B. & Kurniawan, N. 2019.
Study of species richness and structure community of herpetofauna on Kondang Merak
Forest, Malang, Indonesia. In Proceedings of the 6th International Conference on Advanced
Molecular Bioscience and Biomedical Engineering (ICAMBBE 2019), SCITEPRESS, (pp.
89–95). https://doi.org/10.5220/0009586100890095
Kramer-Schadt, S., Niedballa, J., Pilgrim, J. D., Schröder, B., Lindenborn, J., Reinfelder, V.,
Stillfried, M., Heckmann, I., Scharf, A. K., Augeri, D. M., Cheyne, S. M., Hearn, A. J.,
Ross, J., Macdonald, D. W., Mathai, J., Eaton, J., Marshall, A. J., Semiadi, G., Rustam, R.,
Bernard, H., Alfred, R., Samejima, H., Duckworth, J. W., Breitenmoser-Wuersten, C., Be-
lant, J. L., Hofer, H. & Wilting, A. 2013. The importance of correcting for sampling bias in
MaxEnt species distribution models. Diversity and Distributions, 19, 1366–1379. https://
doi.org/10.1111/ddi.12096
Kumar, S., Stecher, G. & Tamura, K. 2016. MEGA7: Molecular Evolutionary Genetics Analy-
sis Version 7.0 for Bigger Datasets. Molecular Biology and Evolution, 33 (7), 1870–1874.
https://doi.org/10.1093/molbev/msw054
Kurniawan, N., Fathoni, M., Assiddiqy, M. F., Septiadi, L., Rijalullah, M. A. 2024. Habitat suit-
ability modelling of Rhacophorus reinwardtii (Schlegel, 1840) in Java, with notes on habitat
characteristics from Malang Region–East Java. Journal of Tropical Biodiversity and Biotech-
nology, 9 (2), 1-16. https://doi.org/10.22146/jtbb.84459
Kurniawan, N., Kadafi, A. M., Fathoni, M., Firmansyah, R., Prabasari, K. & Fauzi, M. A. 2023.
A new distribution record of Polypedates pseudotilophus (Anura: Rhacoporidae) from East
Java, based on morphology and molecular evidence. Russian Journal of Herpetology, 30 (3),
167–174. https://doi.org/10.30906/1026-2296-2023-30-3-167-174
Li, J. T., Che, J., Bain, R. H., Zhao, E. M. & Zhang, Y. P. 2008. Molecular phylogeny of Rhacopho-
ridae (Anura): A framework of taxonomic reassignment of species within the genera Aqui-
xalus, Chiromantis, Rhacophorus, and Philautus. Molecular Phylogenetics and Evolution,
48 (1), 302–312. https://doi.org/10.1016/j.ympev.2008.03.023
Liu, X. L., Huang, J. K., Stuart, B. L., Ai, R. D., Bernstein, J. M., Suwannapoom, C., Chomdej, S.,
Che, J. & Yuan, Z. Y. 2023. Taxonomic revision of genus Rohanixalus (Anura: Rhacophori-
dae) in China with description of one new species. Zoological Research, 44 (6), 1146–1151.
https://doi.org/10.24272/j.issn.2095-8137.2023.179
Lohman, D. J., de Bruyn, M., Page, T., von Rintelen, K., Hall, R., Ng, P. K. L., Shih, H.-T., Car-
valho, G. R., & von Rintelen, T. 2011. Indo-Australian biogeography in the Sunda Arc.
Annual Review of Ecology, Evolution, and Systematics, 42, 205–226. https://doi.org/10.1146/
annurev-ecolsys-102710-145001
Documenting the First Occurrence of Feihyla Baladika (Anura, Rhacoporidae) in East Java
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
241
Naimi, B., Hamm, N. A. S., Groen, T. A., Skidmore, A. K. & Toxopeus, A. G. 2014. Where is
positional uncertainty a problem for species distribution modelling?. Ecography, 37, 191–
203. https://doi.org/10.1111/j.1600-0587.2013.00205.x
Phillips, S. J. 2017. A Brief Tutorial on Maxent. http://biodiversityinformatics.amnh.org/open_
source/maxent/. Accessed on 15 June 2025.
Phillips, S. J., Anderson, R. P. & Schapire, R. E. 2006. Maximum entropy modeling of species geo-
graphic distributions. Ecological Modelling, 190 (3–4), 231–259. https://doi.org/10.1016/j.
ecolmodel.2005.03.026
Posada, D. 2008. jModelTest: Phylogenetic Model Averaging. Molecular Biology and Evolution,
25 (7), 1253–1256. https://doi.org/10.1093/molbev/msn083
Prasetyo, L. B., Kartodihardjo, H., Adiwibowo, S., Okarda, B. & Setiawan, Y. 2009. Journal of
Integrated Field Science, 6, 37–44
Rambaut, A. 2009. Molecular evolution, phylogenetics and epidemiology: FigTree. World Wide
Web electronic publication. 7 (2018), 396-412. http://tree.bio.ed.ac.uk/software/figtree
Rebelo, H. & Jones, G. 2010. Ground validation of presence-only modelling with rare species: a
case study on barbastelles Barbastella barbastellus (Chiroptera: Vespertilionidae). Journal of
Applied Ecology, 47, 410–420. https://doi.org/10.1111/j.1365-2664.2009.01765.x
Rinnhofer, L. J., Roura-Pascual, N., Arthofer, W., Dejaco, T., Thaler-Knoflach, B., Wachter, G. A.,
Christian, E., Steiner, F. M. & Schlick-Steiner, B. C. 2012. Iterative species distribution mod-
elling and ground validation in endemism research: an Alpine jumping bristletail example.
Biodiversity and Conservation, 21, 2845–2863. https://doi.org/10.1007/s10531-012-0341-z
Riyanto, A. & Kurniati, H. 2014. Three new species of Chiromantis Peters 1854 (Anura: Rha-
cophoridae) from Indonesia. Russian Journal of Herpetology, 21 (1), 65–73. https://www.
researchgate.net/publication/26121638
Ronquist, F. & Huelsenbeck, J. P. 2003. MrBayes 3: Bayesian phylogenetic inference under mixed
models. Bioinformatics, 19 (12), 1572-1574. https://doi.org/10.1093/bioinformatics/btg180
Searcy, C. A. & Shaffer, H. B. 2014. Field validation supports novel niche modeling strategies in a
cryptic endangered amphibian. Ecography, 37, 983–992. https://doi.org/10.1111/ecog.00733
Swofford, D. L. 2002. PAUP *. Phylogenetic analysis using parsimony (* and other methods).
Ver. 4, Sinauer Associates, Sunderland
Trifinopoulos, J., Nguyen, L. T., von Haeseler, A. & Minh, B. Q. 2016. W-IQ-TREE: a fast online
phylogenetic tool for maximum likelihood analysis. Nucleic acids research, 44 (W1), W232–
W235. https://doi.org/10.1093/nar/gkw256
Wisz, M. S., Hijmans, R. J., Li, J., Peterson, A. T., Graham, C. H. & Guisan, A. 2008. Effects of
sample size on the performance of species distribution models. Diversity and Distributions,
14, 763–773. https://doi.org/10.1111/j.1472-4642.2008.00482.x
Yodthong, S., Siler, C. D., Prasankok, P. & Aowphol, A. 2014. Phylogenetic patterns of the
Southeast Asian tree frog Chiromantis hansenae in Thailand. Asian Herpetological Research,
5 (3), 179–196. https://doi.org/10.3724/SP.J.1245.2014.00179
Zanaga, D. Van De Kerchove, R., Daems, D., De Keersmaecker, W., Brockmann, C., Kirches,
G., Wevers, J., Cartus, O., Santoro, M., Fritz, S., Lesiv, M., Herold, M., Tsendbazar, N. E.,
Xu, P., Ramoino, F. & Arino, O. 2022. ESA WorldCover 10 m 2021 v200. Zenodo. https://
doi.org/10.5281/zenodo.7254221. Accessed on 15 June 2025.
Zhang, P., Liang, D., Mao, R. L., Hillis D. M., Wake D. B., Cannatella D. C. 2013. Efficient
sequencing of anuran mtDNAs and a mitogenomic exploration of the phylogeny and
evolution of frogs. Mol Biol Evol, 30 (8), 1899–1915.
Received 31August 2025
Accepted 30 June 2026
M. A. Rijalullah, N. Khanifan, M. F. Assiddiqy, Anandhika M.S.P. Soeprijadi et al.
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
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Appendix
Table A1 . Summary statistics and loading for the PCA analysis of F. baladika
from Sumatra and F. cf. baladika from East Java, using 17 allometric
body-size correction characters
Parameter PC1 PC2 PC3 PC4 PC5 PC6 PC7
Standard deviation 3.12 1.68 1.24 1.06 0.92 0.73 0.54
Proportion of variance 0.57 0.17 0.09 0.07 0.05 0.03 0.02
Cumulative proportion 0.57 0.74 0.83 0.9 0.95 0.98 0.99
Eigenvalue 9.76 2.83 1.53 1.13 0.84 0.53 0.29
SVL 0.3 0.04 -0.02 0.07 -0.11 -0.1 0.12
HL -0.3 -0.16 -0.13 0.07 -0.07 -0.07 0.11
HW 0.11 -0.34 -0.41 0.1 0.51 -0.05 0.45
ELW 0.31 0.03 0.12 0.08 -0.06 0.07 -0.05
ED -0.27 0.01 -0.01 0.23 0.18 0.56 -0.4
IND -0.08 0.47 0.27 0.07 0.48 -0.06 -0.08
IOD -0.16 -0.27 0.11 0.63 -0.13 -0.29 -0.23
SNL -0.27 -0.21 0.14 -0.3 -0.07 -0.14 -0.18
DNE -0.21 -0.1 -0.53 -0.16 -0.21 -0.12 -0.35
TD -0.21 -0.25 0.42 0.27 0.17 -0.17 0.09
FLL 0.29 -0.02 -0.13 -0.04 0.34 0.11 -0.38
HLT 0.13 -0.33 0.46 -0.38 -0.16 0.16 0.05
THL 0.26 -0.28 0.02 0.24 -0.06 0.35 0.07
TIL 0.27 -0.29 -0.02 0.08 -0.1 0.26 -0.21
FL 0.2 -0.33 0.08 -0.2 0.35 -0.44 -0.34
3FDW -0.3 -0.18 -0.01 -0.06 0.05 0.21 0.27
4TDW -0.27 -0.19 0.05 -0.27 0.29 0.23 -0.01
Documenting the First Occurrence of Feihyla Baladika (Anura, Rhacoporidae) in East Java
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
243
Table A2 . List of sequence utilized for phylogenetic analysis
Species Locality Country GenBank
accession Reference
Feihyla hansenae
(Clade I)
Nong Khor, Si Racha
District, Chonburi Prov.
Thailand MW054215 Biju et al. (2020)
Feihyla hansenae
(Clade I)
Nam Tok Hongkaew Prov. Thailand AB813161 Matsui et al.
(2014)
Feihyla hansenae
(Clade I)
Wang Nam Khieo district,
Nakhon Ratchasima Prov.
Thailand KC357631 Aowphol et al.
(2013)
Feihyla hansenae
(Clade I)
Ban Ta Khun district, Surat
Thani Prov.
Thailand KC357627 Aowphol et al.
(2013)
Feihyla hansenae
(Clade II)
Longzhou, Guangxi China OR492417 Liu et al. (2023)
Feihyla hansenae
(Clade II)
Shiwan Mountain, Guangxi China OR492422 Liu et al. (2023)
Feihyla hansenae
(Clade II)
Wuzhishan, Hainan China OR492428 Liu et al. (2023)
Feihyla hansenae
(Clade II)
Hekou, Yuannan China OR492423 Liu et al. (2023)
Feihyla hansenae
(Clade II)
Mae Hong son Prov Thailand KJ546826 Yodthong et al.
(2014)
Feihyla hansenae
(Clade II)
Mueang district, Mae Hong
Son Prov.
Thailand KC357653 Aowphol et al.
(2013)
Feihyla hansenae
(Clade II)
Mae Sod district, Tak
Province
Thailand KJ546814 Aowphol et al.
(2013)
Feihyla hansenae
(Clade III)
Phu Hin Rong Kla NP,
Phitsanulok Prov.
Thailand KR827731 Grosjean et al.
(2015)
Feihyla hansenae
(Clade III)
Thung Salaeng Luang NP,
Phetchabun Prov.
Thailand KR827735 Grosjean et al.
(2015)
Feihyla hansenae
(Clade III)
Thung Salaeng Luang NP,
Phetchabun Prov.
Sama koordinate
Thailand KR827733 Grosjean et al.
(2015)
Feihyla baladika Berastagi, North Sumatra Indonesia MW054235 Biju et al. (2020)
Feihyla baladika Tapanuli, North Sumatra Indonesia MW054232 Biju et al. (2020)
Feihyla baladika Tapanuli, North Sumatra Indonesia MW054233 Biju et al. (2020)
Feihyla baladika Rejanglebong, Bengkulu Indonesia MW054234 Biju et al. (2020)
Feihyla cf. baladika Malang, East Java Indonesia PV820714 This study
Feihyla cf. baladika Malang, East Java Indonesia PV820715 This study
Feihyla cf. baladika Malang, East Java Indonesia PV820716 This study
Feihyla senapatiensis Nagaland India MW054218 Biju et al. (2020)
Feihyla senapatiensis Manipur India MW054217 Biju et al. (2020)
Feihyla senapatiensis Manipur India MW054220 Biju et al. (2020)
Feihyla shyamrupus Arunachal Pradesh India MW054222 Biju et al. (2020)
Feihyla shyamrupus Manipur India MW054221 Biju et al. (2020)
Feihyla shyamrupus Nagaland India MW054227 Biju et al. (2020)
Feihyla cf. shyamrupus Putao District, Kachin
State
Myanmar KC692874 Aowphol et al.
(2013)
Feihyla cf. shyamrupus Putao District, Kachin
State
Myanmar KC692875 Aowphol et al.
(2013)
Feihyla cf. shyamrupus Putao District, Kachin
State
Myanmar KC692876 Aowphol et al.
(2013)
M. A. Rijalullah, N. Khanifan, M. F. Assiddiqy, Anandhika M.S.P. Soeprijadi et al.
ISSN 2707-725X. Zoodiversity. 2026. Vol. 60, No. 3
244
Species Locality Country GenBank
accession Reference
Feihyla wuguanfui Kham, Xiengkhouang Laos OR500750 Liu et al. (2023)
Feihyla wuguanfui Naung Layan, Loi Mwe
WS, Kyaitong Township
Myanmar MW054230 Biju et al. (2020)
Feihyla vittata Dewei District, Tanintharyi
Division
Myanmar KC692877 Aowphol et al.
(2013)
Feihyla vittata Sangkhla Buri district,
Kanchanaburi Prov.
Thailand KC357620 Aowphol et al.
(2013)
Feihyla vittata Rangat, Middle Andaman,
Andaman and Nicobar Islands
India MW054229 Biju et al. (2020)
Feihyla vittata Myitkyina District, Kachin
state
Myanmar KC692881 Aowphol et al.
(2013)
Feihyla palpebralis Lang Bian, Lam Dong Vietnam GQ285681 Li et al. (2009)
Feihyla vittiger Pengalengan, West Java Indonesia MW054231 Biju et al. (2020)
Feihyla inexpectata Camel Trophy field station,
Maliau Basin Conservation
Area, Sandakan Division,
Sabah
Malaysia MG909569 Haas et al.
(2018)
Feihyla fuhua Pingbian, Yunnan China EU924620 Yu et al. (2009)
Feihyla kajau Camp 1, Gunung Mulu
N.P., Sarawak, Borneo
Malaysia JN377362 Haas et al.
(2012)
Feihyla kajau Bintulu Division, Sarawak,
Borneo
Malaysia KC465789 Li et al. (2013)
Chirixalus pantaisela-
tan
Leuweung Sancang Nature
Reserve, Sancang, Cibalong
District, Garut Regency,
West Java
Indonesia MT155987 Munir et al.
(2021)
Chirixalus
pantaiselatan
Leuweung Sancang Nature
Reserve, Sancang, Cibalong
District, Garut Regency,
West Java
Indonesia MT155986 Munir et al.
(2021)
Chirixalus pantaisela-
tan
Leuweung Sancang Nature
Reserve, Sancang, Cibalong
District, Garut Regency,
West Java
Indonesia MT155988 Munir et al.
(2021)
Chirixalus trilaksonoi Jasinga, Bogor, West Java Indonesia MT155989 Munir et al.
(2021)
Chirixalus trilaksonoi Bukit Baru, Ilir Barat I
District, Palembang, South
Sumatra
Indonesia PP051252 Herlambang et
al. (2023)
Chirixalus
nongkhorensis
Laos (Vientiane and
Champasak)
Laos GQ204723 Meegaskumbu-
ra et al. (2010)
Chirixalus doriae Kyaiphaung to Win Bo
village, Kyaitong Township
Myanmar MW054213 Biju et al. (2020)
Chiromantis xerampe-
lina
Africa Africa GQ204734 Meegaskumbu-
ra et al. (2010)
Chiromantis rufescens Cameroon Camer-
oon
KF991282 Barej et al.
(2014)
Chiromantis petersii Africa Africa GQ204733 Meegaskumbu-
ra et al. (2010)
Polypedates leucomy-
stax
Java Indonesia GQ204693 Meegaskumbu-
ra et al. (2010)
The end Table A2
|
| id | oai:ojs.akademperiodyka.org.ua:article-838 |
| institution | Zoodiversity |
| keywords_txt_mv | keywords |
| language | English |
| last_indexed | 2026-07-07T01:00:29Z |
| publishDate | 2026 |
| publisher | Publishing House "Akademperiodyka" of the National Academy of Sciences of Ukraine |
| record_format | ojs |
| resource_txt_mv | ojsakademperiodykaorgua/52/3fb6e92e89be5482258081ff5c369052.pdf |
| spelling | oai:ojs.akademperiodyka.org.ua:article-8382026-07-06T23:39:50Z Documenting the first ocurrence of Feihyla baladika (Anura, Rhacophoridae) in East Java: ecology, genetics, and habitat suitability Rijalullah, M. A. Khanifan, N. Assiddiqy, M. F. Soeprijadi, Anandhika M.S.P. Fathoni, M. Nurrofik, A. Kurniawan, N. Septiadi, L. Amphibian Indonesia Phylogeny species distribution model Previously, Feihyla baladika (Riyanto and Kurniati, 2014) was known exclusively from Sumatra, Indonesia. This study reports a new record of this species from the eastern region of Java Island, within a lowland tropical rainforest close to Pantai Kondang Merak. Due to the absence of other findings in Java and some morphological differences along with a genetic distance of 2–3%, we cautiously refer to the specimens as F. cf. baladika. Species distribution modeling using MaxEnt suggests that F. baladika may potentially occur in Sumatra, Java, and Bali, in areas characterized by relatively low precipitation during the wettest month, forest cover, and low temperature seasonality. Publishing House "Akademperiodyka" of the National Academy of Sciences of Ukraine 2026-04-28 Article Article application/pdf https://ojs.akademperiodyka.org.ua/index.php/Zoodiversity/article/view/838 10.15407/zoo2026.03.225 Zoodiversity; Vol. 60 No. 3 (2026): Zoodiversity Zoodiversity (Vestnik Zoologii); Том 60 № 3 (2026): Zoodiversity 2707-7268 2707-725X 10.15407/zoo2026.03 en https://ojs.akademperiodyka.org.ua/index.php/Zoodiversity/article/view/838/404 Copyright (c) 2026 Muhammad Asyraf Rijalullah, Nashrul Khanifan, Miftah Farid Assiddiqy, Anandhika M.S.P. Soeprijadi, Muhammad Fathoni, Luhur Septiadi, Agus Nurrofik, Nia Kurniawan |
| spellingShingle | Rijalullah, M. A. Khanifan, N. Assiddiqy, M. F. Soeprijadi, Anandhika M.S.P. Fathoni, M. Nurrofik, A. Kurniawan, N. Septiadi, L. Documenting the first ocurrence of Feihyla baladika (Anura, Rhacophoridae) in East Java: ecology, genetics, and habitat suitability |
| title | Documenting the first ocurrence of Feihyla baladika (Anura, Rhacophoridae) in East Java: ecology, genetics, and habitat suitability |
| title_full | Documenting the first ocurrence of Feihyla baladika (Anura, Rhacophoridae) in East Java: ecology, genetics, and habitat suitability |
| title_fullStr | Documenting the first ocurrence of Feihyla baladika (Anura, Rhacophoridae) in East Java: ecology, genetics, and habitat suitability |
| title_full_unstemmed | Documenting the first ocurrence of Feihyla baladika (Anura, Rhacophoridae) in East Java: ecology, genetics, and habitat suitability |
| title_short | Documenting the first ocurrence of Feihyla baladika (Anura, Rhacophoridae) in East Java: ecology, genetics, and habitat suitability |
| title_sort | documenting the first ocurrence of feihyla baladika (anura, rhacophoridae) in east java: ecology, genetics, and habitat suitability |
| topic_facet | Amphibian Indonesia Phylogeny species distribution model |
| url | https://ojs.akademperiodyka.org.ua/index.php/Zoodiversity/article/view/838 |
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