Citron barb, a new barb species, spotted from Western Ghats Rivers of Maharashtra

Tweet

Citron Barb (Pethia lutea), a new barb species discovered from Western Ghat Rivers of Maharashtra
(Image Courtesy: Ralf Britz/JOTT)

Researchers studying the fish diversity in Western Ghats Rivers have discovered a yet unknown species of fresh water barb from the Western Ghats River systems in the Indian state of Maharashtra. The new species belongs to the Pethia genus of fishes which constitutes barbs found only in South Asia and Myanmar region.

New bush frog species discovered from Western Ghats of Maharashtra

Tweet

Raorchestes ghatei
(Photo Courtesy: JOTT, Image Credit: Anand D Padhye)

Amidst the ruckus raised by mining lobbies and real estate mafias against the implementation of the expert panel report on conserving the Western Ghats mountain ranges, researchers continue to discover species unknown to science from different parts of this biodiversity hot-spot. The latest in the line is Raorchestes ghatei, a new species of Bush Frog discovered from the Western Ghats in the state of Maharashtra.

According to a study published in the Journal of Threatened Taxa, the new frog species is very different from its closest relatives. Apart from the observable morphological differences, the sequencing study of the mRNA of the newly described frog confirms its identity as a distinct species of bush frogs. According to the research note, ‘molecular phylogeny based on 16S rRNA gene sequence suggests that the new species is genetically distinct and forms a monophyletic clade within Raorchestes, the genus of bush frogs’ to which it belongs.

Researchers came across this enigmatic species from different places in Satara and Pune districts of Maharashtra. They have christened it after Dr. H.V. Ghate known for his contributions to the herpetology of Western Ghats of Maharashtra. According to the researchers, the frog will be known as Ghate’s Shrub Frog.

Based on historical records, the researchers claim that the Ghate’s Shrub Frog is widely distributed in the Western Ghats of Maharashtra. It typically inhabits scrub patches and semi-evergreen forests. The species shows sexual dimorphism due to which males and females of the species look different. In fact, they are different in their behavior too, say the researchers. While the females prefer to hide under loose stones, males usually perch on shrubs and tree trunks up to 5 meters above the ground.

Unlike many other frogs, the new species does not have a free-swimming tadpole stage in its development.  Instead, it shows direct development – emerging as a morphological miniature of the adult from the egg. As per the study, Raorchestes ghatei usually lays egg in loose soil under stones.

Amphibian diversity in Western Ghats

Western Ghats is known for its rich amphibian diversity, the new discovery adds to human efforts to understand it. According to a theme paper on Amphibian diversity prepared by Western Ghats Ecology Expert Panel, India is home to 311 species of amphibians among which 161 are found in Western Ghats. According to the paper, at least 138 species of amphibian species are endemic to Western Ghats. However, much of this diversity was unknown to science until recently and is still getting unearthed. During the last ten years from 2003, at least 37 new species of frogs have been discovered from different parts of the Western Ghats.

According to the new study which described Raorchestes ghatei , though specific threat to the new frog species were difficult to identify, the habitat destruction due to human interference is a major threat to the endemic amphibian diversity in Western Ghats. “Even though no specific threats could be identified for the species, continuous deforestation in these areas leading to habitat fragmentation could be a threat to the species”, says the study. According to the researchers, tourism activities as well as setting up of wind farms are also leading to destruction of amphibian habitat in this area.

Anand D. Padhye and Anushree Jadhav of Department of Zoology, MES’s Abasaheb Garware College, Pune, Amit Sayyed of Wildlife Protection and Research Society, Satara and Neelesh Dahanukar from Indian institute of Science Education and Research, Pune have co-authored the study.

The story of finding the new stone Loach, Balitora laticauda: an interview

Tweet

Western Ghats Rivers have a bounty of yet unknown aquatic fauna. Recently, a new member was added to the Indian aquatic fauna when a group of researchers found that a fish known to villagers living on the banks of Krishna River in Satara District of Maharashtra, is unknown to science. After conducting follow up studies and comparing it with already described similar species in India, they have established that it is indeed a new species. NeeleshDahanukar, IISER Fellow at the Indian Institute of Science Education and Research, Pune who was part of the research team, talks about the finding of the new stone Loach from Krishna River with Indian Biodiversity Talks.

Balitora laticauda, teh new stone loach found from Krishna River in Northern Western Ghats
Image Courtesy: Sunil Bhoite

It is indeed interesting to know that the Western Ghats Rivers still keep organisms new to science. Will you please tell us how your team happened to find the fish?

Sunil Bhoite, who is a naturalist working in Satara District, Maharashtra, first caught this species in 2009 and sent it to Dr. Shrikant Jadhav, a scientist in Zoological Survey of India, Western Regional Center, Pune. 

habitat near Krishna River bridge
from where Balitora laticauda  was found.
Image Courtesy: Sunil Bhoite

During our collaborative work on the freshwater fish diversity of the northern Western Ghats, Dr. Jadhav showed me this species as an interesting specimen of genus Balitora. In 2011, Dr. Jadhav and I had an opportunity to visit the ZSI headquarters in Kolkata during which we studied the comparative material of related species. We realized that the species of Balitora from Satara is indeed a new species, still unknown to science.

In collaboration with Sunil Bhoite, who collected more specimens of the species early this year, Dr. Shrikant Jadhav and I worked on the species description and the findings are now published in Journal of Threatened Taxa. We also received some additional specimens of this fish from another locality in the same river from Madhavi Chavan and comparative material of Balitora mysorensis from Rahul Kumar, which were very important in the study.

Though the fish is new science, it had a local name. Were the locals using the fish for any cultural or other purpose?

This fish does not have any cultural value nor does it have any food value. However, sometimes tribal people (called Katkari) catch these and similar hill stream loaches and sell them in the local fish market. The species, however, is rare and is only seldom seen in the market.

With your finding, it is clear that the Western Ghats Rivers still have aquatic fauna which is yet to be described. Considering the rapid pace at which Western Ghats water bodies are polluted, do you think many of these unknown species will stop to exist even before we find them?

In the recent IUCN report on the threats to freshwater diversity of the Western Ghats (http://data.iucn.org/dbtw-wpd/edocs/RL-540-001.pdf) it was suggested that about 60% of the total endemic freshwater fish species of the Western Ghats are threatened because of several anthropogenic stressors including  organic and inorganic pollution of the water,  biological resource use (food fish and aquarium trade), invasive species, residential and commercial developments and natural system modification.

Typical habitat of Balitora laticauda
Image Courtesy: Sunil Bhoite

Especially in the northern Western Ghats such rapid developments are highly uncontrolled and they are modifying the natural ecosystems posing severe threats to the aquatic biota. On one hand, while the habits of the freshwater fishes, especially the specialists like hill stream loaches that require fast flowing clear water with a good substratum, are getting lost or severely affected; on the other hand we are still discovering species new to science. 

Unless we take efforts for conservation of the habitats and keep a check on the various anthropogenic stressors, it is quite likely that several freshwater fish species will go extinct even before we know them and describe them scientifically. 

Is there any specific threat to the newly described species?

There are no specific threats in the vicinity of type localities of the newly described species. However, potential threats to the habitat include severe sand mining upstream of type locality and agricultural run–off entering into the river. Some organic and inorganic pollution in the area is contributed by the washing of cloths and vehicles. Some river stretches in the vicinity of the habitat also have human settlements which contribute to household wastes directly being added to the river water.