S ixty to seventy million years ago, in a Western Ghats far different from our own, a tadpole hatched out of an egg, distinctly different from its relatives. It lived and survived, spawning generations over millennia, an ancient pulse of life coursing uninterrupted through time.

It’s akin to the wonder space scientists and astrophysicists feel at the universe’s first flush of light after the big bang, the background radiation still reaching us, and stars so far away their light is yet to reach us.

The more we see into space and time, the more we—the frog and us—get resolved into a single root of the tree of life. The frog lay hidden, mostly under a litter of leaves, unknown and unsought, in its undocumented past. Nobody—at least, no biologist—knew about it except perhaps the Kurichiya tribe on the Wayanad Plateau where it lives. Not until it shone bright in the headlamps and camera lights of researchers from the Indian Institute of Science who went on an expedition in 2010. The frog was was not just a new species, but an ancient lineage percolating into the present. The discovery has been published in the journal Peer J.

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T he class Amphibia consists of three orders—the order Anura, which includes frogs and toads, the order Caudata or salamanders, and the order Gymnophiona or caecilians (limbless amphibians that live unseen in the ground). It is thought that frogs split from the other two orders sometime before the supercontinent Pangaea splintered into the present continents. A 2017 paper, published in Proceedings of the National Academy of Sciences of the US, however, suggests the mass extinction event 66 million years ago at the Cretaceous-Tertiary Boundary (KTB) that wiped out dinosaurs, in fact, prompted an explosion of new frog species. The study’s analysis shows that “three species-rich clades—Hyloidea, Microhylidae, and Natatanura—which together comprise about 88 per cent of extant anuran species, simultaneously underwent rapid diversification,” at KTB.

Moreover, “anuran families and subfamilies containing arboreal species originated near or after the KPB (KTB). These results suggest that the K–Pg (KTB) mass extinction may have triggered explosive radiations of frogs by creating new ecological opportunities.”

Biologists are besotted with the radiation of species. Diversity is one of the fundamental patterns of life, according to the study co-author Kartik Shanker, associate professor at the Centre for Ecological Sciences in the Indian Institute of Science, Bengaluru. Even Darwin and Linneaus, 200 years ago, grappled with questions such as why the tropics were so species-rich because the causes and consequences of diversity give us deep insights into evolution and ecology. Over the decades researchers have explored how environmental factors such as temperature and rainfall, biotic factors such as competition and predation, evolutionary factors such as speciation and extinction and distribution might affect diversity. Ecologists also study the importance of diversity and if it can lead to stability in ecosystems. Moreover, recent developments point to how biodiversity can be tapped as a source of food and medicine.

The diversity of amphibians and reptiles particularly captivates researchers. It stems “from the simple idea that we are just a tiny branch on the larger tree of life,” says lead-author Seenapuram Palaniswamy Vijayakumar, now a post-doctoral scientist at George Washington University.

“As systematists,” he continues, “we are driven by this desire to assemble every part of the branch on this tree; as evolutionists, we are driven by a desire to understand how the very branches came into existence and how they changed; as ecologists we are interested in how they interact; as biogeographers we are curious how and why they are distributed in space; and as conservationists we propose strategies to preserve the major branches of life.

“And for all this biodiversity is the key.”

Vijayakumar says amphibians are among the best organisms to understand how a species came into existence, to decode how a trait evolved, to answer why certain areas have more diversity than others, to understand the history of place.

Our ecosystems are so poorly explored for most species that you are bound to find new species. The important part is to conduct the surveys systematically and be consistent in the criteria for description.

“They can be good proxies for highlighting the importance of a place. They can be good signals—as climate change becomes a reality these groups that depend on the external temperature for survival are expected to show early warning signals.”

Frogs are considered “indicator species”. Their very presence points to the health of an ecosystem.

The sheer wealth of diversity and endemism in the Western Ghats still remains unexplored. A few species set up shop in some strange place, struggle to survive, adapt to that environment over the course of generations, transforming themselves to be in tune with that environment and become endemic to that place. Isolation begets endemism. Ensconced in niches in the hills, without any chance to breed with others, the species become gradually distinct and, finally, wholly different. The Western Ghats teems with endemic species, to be found nowhere except there, in addition to other native and invasive species.

“Our ecosystems,” Shanker says, “are so poorly explored for most species that you are bound to find new species. The important part is to conduct the surveys systematically and be consistent in the criteria for description. The studies that describe one species here and there do not provide a holistic understanding of systematics (naming of species and classification) or biogeography.”

Charles Darwin, marvelling at the diversity of the Galapagos Islands, which are called a “natural laboratory,” for studying how evolution works, wrote in Voyage of the Beagle, “The archipelago is a little world within itself. Both in space and time, we seem to be brought somewhat near to that great fact—that mystery of mysteries—the first appearance of new beings on this earth.”

Had Darwin visited the Western Ghats, he would have, without being carried away, called the hills “the crucible of life”.

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I t took some doing for researchers to meet the frog in the hills. They had to first design the study. Developed during Vijaykumar’s Ph.D, which was on bush frogs, its aim was to find out as many closely-related species as possible across the valleys and peaks in the hills.

“We decided to work backwards from how species diversify,” Shanker says. “We expected that a large proportion of amphibian species would diversify (become species) by geographical separation from each other or along environmental gradients. We used this to design our sampling strategy so that we could find the closest relative of each species.”

“You address two shortfalls, the Wallacean Shortfall (lack of distribution data), in parallel with Linnean Shortfall (occurrence of new species), and combine it with a third one, Darwinian shortfall (lack of understanding of their systematic relationship) to address the questions,” Vijayakumar chips in.

The first, he explains, gives a clear picture of geographical range of species.

The second makes it possible to sample for most known and unnamed lineages/populations. The third, he adds, gives “a hypothesis of the phylogenetic relationship among the known and unknown lineages”.

They took a biogeographic approach to sampling and divided the Western Ghats into 14 hill ranges and thought the valleys between could cause speciation.

The idea was if they sampled for species from different habitats along elevation gradients as well as across mountain ranges, and build a tree of their relationship—using genetic data—they could infer the causes of speciation.

“To simplify, will the immediate relatives of each species (sisters) be within a mountain (sympatric), e.g., in the montane islands (shola/grassland), across a similar elevation on different mountain tops separated by the deep valley (allopatric), or occur on adjacent habitats within a mountain slope (parapatric).”

They also focused more on the southern Western Ghats, which they expected would have more species because of its greater area and as lower altitudes are generally rich in species.

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C

lues to the rich biodiversity of the Western Ghats go way back in time. Mountains in the tropics, in general, are hotspots of biodiversity. The topography, formed by geological convulsions, and the consequent landscape changes, inhabits, as Shanker puts it, “gene flow,” and propels bursts of speciation.

“There are multiple environmental gradients (rainfall, temperature) that also promote divergent selection and eventually diversification,” he says.

In the Western Ghats, specifically, he says, the historical connection with Gondwana means that there are several taxa of Gondwanan origin, but also colonisation by taxa of Asian origin after contact with the Asia.

Finally, he adds, the southern Western Ghats has been hypothesised to be a Pleistocene refuge, which means that many lineages would have survived there during glacial periods.

Vijayakumar says the evidence of the number of large endemic radiations, especially of frogs, makes the Western Ghats the centre of diversification. He notes that one or two radiations are known to have sprung from birds too.

While the drivers like geology and landscape changes and others are significant, they would each differ in effect depending on the taxonomic groups.

“Our work suggests the way this mountain formed also has a role in diversification. Only future studies can reveal the generality of these hypotheses,” he says.

“The presence of ancient lineages, in the southern Western Ghats, suggests, these regions might have acted as a refuge: a museum. Paleoecologists and Biogeographers have long hinted that the Western Ghats might have served as a climatic refuge. And, what we see could be the legacy of what happened during the Eocene and Miocene.”

He mentions “dispersal from adjoining regions over long periods,” as another critical factor that contributed to the diversity.

“In this sense, they could have acted as sinks. It is more evident in birds which are characterised by very few endemic species. One thing you need to understand is that we are just a few steps into testing a number of these various hypotheses.”

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W

hen Vijayakumar started studying ecology, around 20 years ago, he found that species were misidentified in many reports on ecological field studies of frogs conducted during the early 1990s and 2000s.

“I know this now, but I didn’t then. There were issues of species identity and lack of information on species distribution,” he says.

He already knew, from his field experience in 1996 with wildlife sound recordist Siva Prasad, that there were more unique calls than the number of species reported in historical literature. He also knew that most species reports were based either on a single site, or unknown or lost.

His background in ecology primed him to address the lack of knowledge of species distribution.

In 1999, sampling across shola forests—natural forest fragments surrounded by grasslands—in the Palani Hills during the cold winter months (when the frogs are quiet), his scepticism about species identification was at an all-time high. But he was relatively confident about assigning species to a genus. Since most genera had one or two species it was quite straightforward to map their distribution across the shola fragments and grasslands.

“But bush frogs appeared to have more species. Their distribution created confusion,” he says.

After short stints in a dry forest and a cold desert, he decided the Western Ghats was too complicated, and set sail for the Nicobar archipelago in search of answers in island biogeography. He went on expeditions to 15 islands and tried to map the distribution of frogs, lizards, and snakes. The islands ranged from less than one sq. km. in size to greater than 1,000 sq. km. He established more than 200 new geographical records for all the species combined from 15 islands. Although he was content at one level, he was dissatisfied with the identity of species.

“The complexity was that most species have their relatives distributed in Sumatra and Peninsular Malaysia,” he says.

Then calamity struck. On Dec 26, 2004, a tsunami swept the Nicobar Islands, resulting in the loss of a number of his friends, leaving others bereft and forlorn. He then attempted to assess the damage post-tsunami, and returned with a decision to quit his efforts to continue his Ph.D. in the islands till the human communities recovered.

“The thing, apart from the human side of this that I learned about biogeography is that, distribution is fascinating, but without solid systematics it can be shaky,” he says.

In 2006, Shanker and the Centre for Ecological Sciences (CES) at IISc gave him an opportunity “to explore a problem for my Ph.D”. Around 2007-08, while was on an expedition in search of questions for his Ph.D accident struck: a tree rolled on his leg, leaving his foot dislodged from his leg and fibula broken. It shattered him, blowing away his dreams of climbing hills or hopping on stream boulders. He was bedridden for six months, while his colleagues had started research. When he was better, he spent three months limping to the institute from home, still searching for questions and poring over literature.

“You think deeper in a crisis. But deep inside I had a love for bush frogs—which goes back to 1996, my first sighting.”

In the early 2000s, researchers in Sri Lanka had reported some 200 species of bush frogs and there were similar reports in the Western Ghats as well. He remembers more than 90 were bush frogs.

Vijayakumar says that CES’s research focus was on questions in ecology, evolution and behaviour, especially those that had a strong scientific theoretical basis. So, instead of focusing on “how many frog species are there?” for his Ph.D, he decided to ask “what drives their diversification (speciation)?” The two questions were related, though.

Bush frogs had always intrigued Vijayakumar, with their diversity and other characteristics. He thought they would provide a window into evolution in the Western Ghats, and could be a good model system. Taxonomy, however, remained a problem. Having left the Western Ghats thinking it was too complicated, then having suffered a leg injury, he returned once more to tackle the question of diversity and its drivers with a more focused approach.

It was a surprise when Shanker told Vijayakumar that his own first attempt at a Ph.D was on bush frogs in a montane landscape in Nilgiris. Considering their taxonomic complexity, Shanker instead worked on small mammals.

Although there were risks of not completing his Ph.D, it didn’t matter, “having experienced that once before”. New tools in phylogenetics and his field experience in the islands gave Vijayakumar confidence. He presented a proposal to Shanker. After many brainstorming sessions, Vijayakumar started the design process of his study.

Maps prepared by researchers from the French Institute and elevation profiles of vegetation were helpful in refining the design. The geologists’ division of the Western Ghats fed into the design as well. Using digital elevation models of the Western Ghats, which help outline all the major mountains, valleys and plateaus, Vijayakumar made maps. Depending on the vegetation communities on the slopes, they divided each hill into three to five zones across 15 mountains.

Next was the “the daunting task of choosing sites within each of the identified locations and sample for species. I wasn’t prepared for the surprises like the ancient lineages, failures, and enormity of the mission.”

In their first field expedition in 2008-09, using calls to track individuals, he came back with a windfall of unidentified species. When he returned, a professor from his department stopped Vijayakumar in the corridor and told him that there was report of a dozen new species in a newspaper, maybe The Hindu. He discovered that S. D. Biju, known as the frogman of India, had published 12 new species of bush frogs.

Vijayakumar had most of them in his collection. Initially he was worried, but once he examined the sampling sites, he knew that there were more unexplored areas that could hold unknown species.

“I was happy! The game of species hunting is not over yet!”

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M

aps ready, Vijayakumar now had guidance to go up the high-elevation hills, especially the ones above 1400 metres. The goal was to understand what caused bush frogs to split from a common ancestor into multiple species today. And the mountains, he and Shanker believed, held clues to the origin of bush frogs.

Field work for outsiders is all excitement and thrill. But that romantic vision is partly fantasy. For insiders, though, it’s where they sometimes stop thinking of science. It’s often frustrating, mostly exhausting, always unpredictable. It’s long hours out in the cold and dark, time spent sampling, recording, photographing, preserving, writing notes, being a martyr to mosquitoes, snakes, and leeches. It’s eating with the remaining clean fingers, sleeping in tents and tin-roofed sheds.

It’s also having each other’s back, lest you tumble down a precipice or are flung away or trampled by elephants while chasing, well, a critter of your choosing.

After climbing many high hills, they came to a range of hills standing like a wall along the rim of the Wayanad Plateau. They started off for Kurichiarmala with a long journey in a 4x4 that Vijayakumar drove, on steep, narrow, precipitous, boulder-strewn roads. They reached before sunset, and ended up at the summit, in a grassland next to a forest station, their base camp for the next few days.

Since frog action starts at night, they would venture out just before dark, when the cicadas create a reverberating sound, which then tapers to the calls of bush frogs.

It was on one of those evenings that Vijayakumar heard “a chuck,” the call of a bush frog.

The plan, as usual, was to locate an area where there was a stream, and team members would go sampling for frogs, lizards, and snakes. A local guide led them to the forest edge, from where they eased into more breathable, but dark forest floor.

Vikayakumar’s ears were perked up for the calls, especially those of bush frogs. He had a Marantz digital recorder with a long shotgun microphone ME67. All he could see of others was Petzel (a France-based company that manufactures head-lamps and gear) spotlights emanating from their heads. He finished his first recording of one “very interesting bush frog”.

“Every step, there was excitement, a call from one of the team members. An interesting torrent toad in the stream; a snake under a stone or a log, some odd looking agamid (lizard) trying to catch some sleep amid our bright light. Overshadowing all this excitement was the loud orchestra of bush frogs.” he says.

He kept moving from one bush to the other, recording individuals and reached a swampy, wet forest floor close to the stream. Then there was an odd call. He couldn’t record it because he got distracted by a new call on the trees.

Returning to base, he started photographing the frogs collected by the team. When he came to one specimen, he was momentarily stunned, looking through a Canon viewfinder, by the beauty of the light blue spots on the body. To document body patterns, researchers also document the ventral side (underside) of the frogs. When Vijayakumar turned the frog over, another surprise awaited him, a striking bright orange.

“By this time, I had made up mind that it was another new frog on our list,” he says.

A few days later, they vacated the camp, but another surprise awaited him. He went on a solitary walk in the morning on the wet grassland trail. While looking out for leeches, a tiny frog with an unusual gait strained through the entangled grass clumps. It was not hopping. On instinct, in an instant, he picked it up to see, and it was “the same fellow the team struggled to locate one of the previous nights”.

Then he had an even tougher expedition planned to a nearby hill range. They drove down, almost entirely in first gear, from the cool montane conditions at around 1400m, down to 900 m into the Wayanad Plateau. When they started, there were around 20 species in the literature; by the end of all other expeditions, they had 70.

Researchers usually collect, with requisite permits from forest department, three to four specimens of species they consider new. They take photographs of live specimens at the site and in controlled conditions with light. Following standard scientific protocols, they dispatch its soul to its Maker, euthanising the specimens with Tricaine methanesulfonate. Then one or two individuals are doused in 70 per cent alcohol for 24 hours for further use in molecular studies and one or two specimens in formalin, (which is a 40 per cent solution of formaldehyde) for long term preservation. Later, all the specimens are preserved in 70 per cent alcohol for further analysis.

After lab studies are completed, the “type specimens” are deposited with national zoological collections in repositories at institutions such as the Zoological Survey of India (ZSI) and Bombay Natural History Society (BNHS), with appropriate registration numbers. These repositories are accessible to researchers who study them. The samples, once deposited, become “national property” and are not allowed to be taken out of the repositories.

They collected five specimens of the frog. “Never in my dreams did I think that this frog would bring so many (of our own and) international experts together to resolve its status,” says Vijayakumar.

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T

o resolve its taxonomy, the team adopted an “integrated taxonomy” approach. Earlier, taxonomy relied mostly on museum samples and form and structure of species. With technological advancement, taxonomists use, in addition to external features, molecular tools, osteological (bone structure) details, ecology and behaviour and call patterns to determine the status of species.

After describing a new species taxonomists classify it. The hierarchy proceds as follows. On the lowest rung is species, at the next level is genus, still higher is sub-family, and next is family. In ascending order, from species to family, more and more general characters of species appear, while in descending order, from family to species, more unique characteristics appear. Names of hierarchies follow conventions of the International Commission on Zoological Nomenclature (ICZN).

To describe species form and structure, they enlisted K. P. Dinesh, a scientist at the Zoological Survey of India(ZSI), Pune.

Dinesh started his amphibian research with ZSI in April 2005 where he specialised in morphological taxonomy. He soon realised that morphology alone would not solve the problems in describing species. He left ZSI for post doctoral research in May 2010, and was part of Shanker’s lab at CES, IISc from June 2010 to May 2015, to learn molecular tools and the importance of biogeography in taxanomy. He then took a break, and rejoined ZSI in May 2017. He has been there since then.

Vijayakumar had a hunch that this was a new species from the day he collected it, but elevation to sub-family level took a long time. Around 2013-14, they all sat together in Shanker’s lab at IISc to discuss the unique morphological characteristics and phylogenetic relationships.

Amphibian taxonomy, Dinesh observes, started in India in 1799, and any attempt to describe a new species requires knowledge of all previous work. When he tries to describe a new species, he compares the morphological characteristics of the new species with all known species since 1799. He bases his studies on literature and physical examination of specimens at zoological collections. He says “integrated taxonomic approach” greatly benefited his work.

Dinesh visited the Kurichiyarmala Hill ranges in 2017 to relocate the frog. He found it secretive.

When Dinesh went to relocate the frog, he used the GPS coordinates from Vijayakumar. (Because of habitat specificity of most groups of frogs, researchers take the help of the record of coordinates. That’s how they go for explorations. The GPS coordinates were recorded when Vijayakumar found the frog in 2010 from the grassland edge near shola forest.) Dinesh went to the place where Vijayakumar had found it, and searched there for two to three hours, finding nothing. Later, he searched near water bodies, “during nights, that’s where we find many frogs in non-rainy days”.

He saw only a few Nyctibatrachid and Micirixalus frogs. Next, he searched in swampy and slushy areas of the forest, “this is where we get most of the semi aquatic Nyctibatrachid frogs”. He continued searching from swampy areas to dry part of leaf litter and almost after three to four hours of search, he says, “I got my ‘first frog’ down below the leaf litter.”

Later, he focused only below leaf litter and he could see a good number of individuals in next one hour.

“They were quick to respond to any slight disturbance,” he says.

He says Vijayakumar had a hunch that this was a new species from the day he collected it, but elevation of the new species to sub-family level took a long time. Somewhere around 2013-14, they all sat together in Shanker’s lab at IISc to discuss the unique morphological characteristics and strange phylogenetic relationships. Their first attempts had already revealed it did not match any description of frogs from the Western Ghats and India.

Although they knew this was a new species, the early attempts at morphological, genetic and osteological analysis were not giving them a complete picture, so they decided to collaborate with Alex Pyron of George Washington University for phylogenetic studies and, Edward L. Stanley and David C. Blackburn from the Florida Museum of Natural History University of Florida for osteological data interpretation.

Shanker says they had preliminary discussions with Alex Pyron and were aware of his global dataset. “Since the frog’s relatives were not easily identified, we requested him to collaborate so that we could locate the frog on a global phylogeny,” he says.

Pyron’s dataset contains genetic information (DNA sequences) from 4,061 species of amphibians—about 50 per cent of all species—generated over decades by researchers worldwide. His research has involved gathering all these data so that “we can simultaneously analyse the amphibian tree of life”.

The dataset helps, he says, in understanding how the new species is related to all other frogs, and estimate the age of these relationships based on the amount of genetic divergence.

Pyron explains that the process of teasing out relationships is handled by very complex algorithms. “We analyze part of the genome of the species to understand its genetic code: ATCGTAGGATTA etc.; the DNA sequence. Then we use a statistical technique to determine how the DNA sequence evolved; this indicates the pattern of relationships between species. We can also analyse the morphology of the animal, its skeleton, skin, organs, etc., and compare them among species to determine how they are related.”

Genetic divergence, Pyron says, is the difference in DNA sequences in the genome. That helps in estimating the age.

“For instance, you are 50 per cent in common with your mother and father in DNA, or nearly 100 per cent if you have an identical twin. This similarity decreases over time, so if we find that two frogs are 1 per cent different, perhaps they diverged 1 million years ago. If they are 10 per cent different, perhaps it was 10 million years ago. “

The tree of life is the “single diagram that links all living things together according to their history on earth. We can reconstruct it using DNA and morphology. In terms of value, it encodes the natural heritage and biodiversity of everything on the planet, everything that we cherish,” Pyron says.

Similarly, they had been contributing to Dave Blackburn’s oVert project and met Ed Stanley when he visited India. They requested them to collaborate on describing the frog’s osteology. The openVertebrate (oVert) project is a thematic collections network funded by the US National Science Foundation. It aims to CT-scan an intact fluid-preserved specimen representing every living genus of vertebrate based on scientific collections in the US. With these data in hand, Blackburn says, “we are then able to provide comparisons to unusual new genera.”

When I was working on this frog, I was sure it was going to be a new species. However, I was not expecting an entirely new sub-family!

Blackburn says his and Stanley’s role in the project was “to determine how this new species might differ in its internal anatomy from closely related lineages in the Western Ghats.”



When they examine the skeletons of frogs, he continues, “We are looking for features that vary among different evolutionary lineages. We often look for particular parts of the skeleton that show high levels of variation, for instance in the skull or shoulder girdle. But we also have to be on the lookout for other features that might vary in unexpected ways.”Their examination shows differences in its various parts of internal anatomy such as nasal, sternum, clavicle, ilium, and others.

In addition, Achyuthan Srikanthan’s taxonomic illustrations and CT scans of skeletal structures and Priyanka Swamy’s efforts in generating genetic data, and Varun R. Torsekar’s voluminous data on Nyctibatrachus, all from Shanker’s lab, helped complete the study.

“When I was working on this frog, I was sure that it was going to be a new species. However, I was not expecting it to be an entirely new sub-family! The discovery of a sub-family does not happen very often, so it was a pleasant surprise,” says Torsekar.

Dinesh believes that the frog will have a family of its own. Its ventral color pattern, closely resembling the species Leptodactylodon boulengeri (Family: Arthroleptidae) from Central Africa, the triangular finger and toe tips resembling frogs of the group Eleutherodactylus (Family: Eleutherodactylidae) from South America and Heleophrynid frogs of South Africa; very primitive nature of its eye characters, skin characters, hand and foot—all of these, the researchers believe, may “support recognition of Astrobatrachidae as a distinct family in the future”.

Unlike most other frogs, which come out in the dark to start croaking, this frog, under slight exposure to light, looks for leaf to hide, Dinesh says.

Eventually, the discovery, published in the journal PeerJ, named the frog Astrobatrachus kurichiyana: Astrobatrachusto highlight the starry spots on the side of its body and kurichiyana to honour the “Kurichiya” tribal community of Wayanad in Kerala, where specimens of this new species were found.

“The species has been assigned to a new sub-family Astrobatrachinae, its closest relatives being Nycibatrachinae (with the genus Nyctibatrachus) in the Western Ghats, and Lankanectinae (with the genus Lankanectes) in Sri Lanka.” says Dinesh.

(Family: Nyctibatrachidae; Sub-family: Astrobatrachinae; Genus: Astrobatrachus; Species: Astrobatrachus kurichiyana.)

Researchers suggested an English name: starry dwarf frog. Moreover, Dinesh observes, its ventral colour closely resembles Leptodactylodon boulengeri (Family: Arthroleptidae) from Central Africa and the morphological triangular finger and toe tips resemble a frogs of the group Eleutherodactylus (Family: Eleutherodactylidae) from South America and ‘Heleophrynid’ frogs of South Africa.

“This itself will explain how much we know and how much we are yet to explore to understand the complexities of nature.” he says.

Shanker thinks that it “may point to convergent evolution, but we will need to examine the ecology more closely.”

When a new species is found, it shows a new evolutionary lineage that is genetically distinct, and shows difference along other lines such as morphology, or is geopgraphically separated, Shanker explains.

The ease of obtaining genetic data, which can distinguish closely-resembling species, and detailed phylogenic analysis have opened a new line of evidence, namely genetic-divergence axis. Morphological accounts and comparisons, however, remain central to species description.

Shanker invokes geography as yet another line of evidence. “We make the case that lineages that are genetically distinct and geographically separated can be considered as species, even if the morphological differences are small.”

That calls for “detailed and systematic surveys of the sort we have been carrying out.” The latest discovery is a back-to-back discovery of frogs in the Western Ghats. In February, there was the discovery of another “mystery frog” in the Western Ghats.

“The discovery of two new frog genera within a span of one month from Western Ghats perhaps indicate that the game is on,” says Abhijit Das of Wildlife Institute of India, Dehradun. He is not involved in the research here.

Frogs have just set the tone, lizards are to follow, and as news of snakes starts to trickle in, brace yourself for some exciting discoveries from young explorers.

“I liked this paper for its elaborate phylogeny and morphological description based on extensive osteological study,” he adds.

In the era of extinction, Dinesh says, new discoveries help counter “nameless extinctions”, by providing a name and bringing the attention of park managers and the global community.

“Our hope is to at least get formal scientific names for species before they disappear in the wild”, says Blackburn.

Vijayakumar is optimistic that “there are no confirmed reports of extinction of any frog from the Western Ghats of Peninsular India, thanks to the extensive tracts of forests, indigenous communities, and years of conservation efforts by people. Except for the unknown effects of global climate change, these discoveries from outside protected areas provide hope for finding more.

“Frogs have just set the tone, lizards are to follow, and as news of snakes starts to trickle in, brace yourself for some exciting discoveries from young explorers. Whoever is listening, we have a history of underestimating the significance of the Western Ghats and its mother region Peninsular India (and other less known hotspots like Eastern Himalayas and the islands). They hold immense potential for anyone who is ready to venture into the wild in search of answers. Huge surprises await all of us."