Sri Lankan researchers have
identified and described eight new frog species from the Peak of Wilderness sanctuary
region which comes under the Central Highlands World Heritage Site in Sri Lanka
during an amphibian survey in the island nation recently. According to a
research paper
published in the Journal of Threatened Taxa, all the newly
described frog species belong to
Pseudophilautus genus of Sri Lankan endemic frogs.
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Bambaradeniya’s Shrub Frog
(Pseudophilautus bambaradeniyai) |
According to the researchers who
have conducted the study, all the new frog species has a combination of unique
features which make them distinctive from other known species of the genus and easily
identifiable in the field.
Since the records are new and
many of them are spotted from only one location so far- from the sanctuary situated in the Ratnapura district in Sabaragamuwa
province of the island nation- all the new species except one(Pseudophilautus
newtonjayawardanei) is considered as
Critically Endangered as per IUCN criterion, says the paper. Organisms with an
extent of distribution of less than 100 square kilometers in habitats under
severe threats are categorized as Critically Endangered categories.
New Bush frogs in Sri Lanka
Bambaradeniya’s Shrub Frog (Pseudophilautus bambaradeniyai), a
small sized frog, found in forests at elevations ranging from 750 to 1400 MSL,
usually rests on the forest floor or on shrubs with a height of about 1.5
meters, says the study. This frog inhabits lowland rain forests and lower
montane rain forests.
 |
Dayawansa’s Shrub Frog
(Pseudophilautus dayawansai) |
Apart from a dark brown dorsal area with black blotches, this frog has
and a blackish cross between the eyes. The off-white stripe on the back is also
very prominent in this frog, according to the study. However, the colour of
dorsum may change to orange to lighter brown while the thickness of the line on
the back may vary from organism to organism. The species was named bambaradeniyai,
after Channa Bambaradeniya, a wetland scientist, for his extensive
works to wetland conservation and conservation attempts.
Dayawansa’s Shrub Frog (Pseudophilautus
dayawansai), is a small bush frog with blackish brown colouration. Its colour
pattern is very different from its close relatives. Sometimes, the blackish
brown tint can vary from reddish-brown to lighter brown shades, according to
the paper. The most preferred habitat is cloud forests at an elevation of
1550-1900 MSL. They are usually found on the forest floor or on bushes of up to
2 meters height.
Apart from several morphological differences,
the frog species also reportedly has three prominent blackish-brown circular
spots among which two are situated between eyes. The frog was named after Nihal
Dayawansa, a senior lecturer in the University of Colombo for his contributions
to amphibian research in Sri Lanka.
 |
Jagath Gunawardana’s shrub frog
(Pseudophilautus jagathgunawardanai) |
Another newly described species, Pseudophilautus
jagathgunawardanai, has a combination of different morphological characters
which makes it different from its close relatives. With the unique patterns and
markings on the dorsum of this light brown frog with a greenish tint, P. jagathgunawardanai
is also an inhabitant of cloud forests at 1600 to 1750 MSL elevations, like
P. dayawansai. Though it may be spotted on the forest floor, these frogs
often prefer to be on tree trunks with lichens. Named after Jagath Gunawardana,
a Sri Lankan naturalist for his conservation efforts, the frog is also known as
Jagath Gunawardana’s shrub frog.
Yet another new frog species, Pseudophilautus
karunarathnai, has unique colour patterns which make it easily identifiable
in the field. Named after Y.G.P. Karunarathna, retired Assistant Director of
Sri Lankan Wildlife Conservation Department, for his efforts to bring down human-wildlife
conflict, the frog has a dorsal portion of uniform cream colour with dark brown
or light brown blotches and a dark brown cross between the eyes.
 |
Karunarathna’s Shrub Frog
(Pseudophilautus karunarathnai) |
Known as Karunarathna’s Shrub Frog, it is
found in lowland rain forests and lowland montane rain forests. It either rests
on forest floor or on shrubs of 1.5 meter height. Interestingly, this frog species
can also be found at places with less canopy cover, like home gardens, says the
study.
Pseudophilautus newtonjayawardanei, is a bronze coloured frog with dark brown
patches and an off-white vertebral stripe on its body. The species has a pair
of broad dark brown longitudinal dorsal bands which starts from the back of the
eye running to the groin region. Named after surgeon naturalist Newton
Jayawardane, it is found in forest canopy in high altitudes. The researchers
were able to find just two specimens of this rare frog which usually sits on
leaves of trees with 8 meters height at forests of 1800 to 2000 MSL elevation.
 |
Newton Jayawardane’s Shrub Frog
(Pseudophilautus newtonjayawardanei) |
Pseudophilautus puranappu, the only one among
the newly found to be named after a freedom fighter, is named to honour Veer
Puran Appu who revolted against the British colonial forces in the pre-independent
days of the island nation. The frog species has a unique faint stripe between
eyes with light greenish tinge on laterally. The species also has a maroon
coloured hour-glass shaped broad patch running from snout to vent. Also known
as Puran Appu’s shrub frog, the species can be seen perching on rocks under
shades during day time. They can be also found on bushes with 1 meter heights
during night. They can be found in forests of elevation ranging between 1800 to
2100 MSL.
The newly christened Samrakoon’s Shrub Frog (Pseudophilautus samarakoon) has a very prominent dark brown ‘M’ shaped patch on its anterior which makes it distinct in the field. Moreover, it has a dark brown band between the eyes. Moreover, there is a combination of other morphological differences which makes this frog distinctive from its close relatives. This new species got its name from the Assistant Director of the Wildlife Department, Ananda Vijith Samarakoon for his efforts to orient the wildlife officers training to optimize the conservation efforts.
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Puran Appu’s Shrub Frog
(Pseudophilautus puranappu) |
|
 |
Samrakoon’s Shrub Frog
(Pseudophilautus samarakoon) |
|
Found at elevations of 1000 to 1400 MSL, Samarakoon ‘s shrub
frog inhabits lower montane rain forests and prefers to perch on bamboo plants
near forest streams or on shrubs with up to 2 meters of height. These species
can be found along with P. bambaradeniyai sp. and P. karunarathnei sp. According to the researchers, the frogs can
be easily found in abundance near the starting point of Kaluganga River.
Pseudophilautus sirilwijesundarai, is a multi-coloured frog with dark brown
dorsal area with greenish tinge and maroon blotches. It has prominent maroon
cross bands on its fingers and toes. Named after Siril Wijesundara who is the Director of Royal Botanical gardens,
Peradeniya, Sri Lanka, is again inhabits
montane cloud forests of 1600 to 1700 MSL elevation. These frogs, according to
the researchers, are usually found on the canopy on tress of even up to 10
meter tall. They are often found with mosses, says the study.
Threats to Herpatofauna
in Sri Lanka
 |
Siril Wijesundara’s Shrub Frog
(Pseudophilautus sirilwijesundarai) |
However, there are multiple threats to the
endemic amphibian fauna in Sri Lanka, say the researchers. Sripada Peak, the
area from the newly described species are reported is a major pilgrim centre.
The
pilgrim tourism in this area and the resulting garbage and pollution is
seriously damaging the fragile ecosystem of the area. Moreover, illegal gem
mining on the banks of the Kalaganga River and illegal felling of trees in the
forests to expand the adjoining tea plantations also is a major threat to the
endemic amphibian diversity in the area, says the study.
Pseudophilautus is a genus of amphibians which include direct
developing rhacophorids (also known as bush frogs or shrub frogs which are
found in Asian and African regions). However, concerns are rife that the genus
is facing survival threat as almost 17 species of the 65 species known from the
genus are never again recorded after their initial discovery and are considered
as already vanished.
According to researchers, this rich biodiversity spot may still have
organisms yet unknown to science, since the population surveys in these are
scarcely conducted due to difficult terrain, heavy rainfall and
inaccessibility.
L.J. Mendis Wickramasinghe, Dulan
Ranga Vidanapathirana, M.D. Gehan Rajeev, S. Chathuranga Ariyarathne, A.W.
Amila Chanaka, L.L. Dharshana Priyantha, Imesh Nuwan Bandara and Nethu Wickramasinghe
of Herpetological Foundation of Sri Lanka, Hendala, Wattala, Sri Lanka have
co-authored the study.
