New Frog Species ‘Ingerana occidens’ Discovered in Meghalaya’s Garo and Khasi Hills

Overview

A new species of frog named  Ingerana occidens , or the western trickle frog, has been discovered in the canopy-covered streams of Meghalaya. It is smaller than its northern relative, has smooth skin with a side stripe, and protruding eardrums. Its genetic code differs by 18% from the northern species.

A Tiny New Frog in Meghalaya

Deep in the canopy-covered streams of northeastern India, a researcher has found a new species of frog. It is called  Ingerana occidens , or the western trickle frog. The discovery was made in the  Garo and Khasi Hills of Meghalaya , south of the Brahmaputra River. This area is rich in biodiversity. Many new species are still waiting to be found. This frog is special because it is the westernmost known species of its genus. Its name ‘occidens’ comes from the Latin word for ‘west’. Let us learn more about this tiny amphibian.

How It Was Discovered

Scientists collected frogs from both sides of the Brahmaputra River. They compared the frogs from the south (Meghalaya) with the frogs from the north (topotypic  Ingerana borealis ). They then examined their DNA. The results were surprising. The southern frogs showed an  18% difference  in their genetic code compared to the northern frogs. Such a large difference confirms that the southern frogs are a completely separate species. They are not just a local variation. They are a new species, never documented before.

Physical Features: Small, Smooth, and Striped

The newly discovered  Ingerana occidens  is a small frog.  Adult females reach only 26 millimetres in length . That is about the size of a human thumbnail. Males are even smaller.

Here are its main features:

• Skin texture:  Mostly smooth with only mild wrinkling. In contrast, its northern relative ( Ingerana borealis ) is heavily wrinkled.

• Colour:  It has a  distinct stripe of contrasting colour  running down its side. This stripe is very noticeable.

• Eardrums (tympanum):  Its eardrums are  clearly visible and protruding . They are topped by a strong fold of skin. In contrast, the northern species has practically invisible eardrums.

These features make it easy to tell the two species apart.

Habitat: Canopy-Covered Streams

The western trickle frog lives in  canopy-covered streams . These are small, shaded streams that flow through dense forests. The tree cover keeps the water cool and clean. The frog is likely adapted to this specific environment. It probably lays its eggs in the water, and the tadpoles develop there. The adult frogs may hunt small insects near the stream banks. Because the habitat is very specific, the frog may be found only in a limited area. This makes it vulnerable to deforestation and climate change.

The Brahmaputra River as a Natural Divide

The Brahmaputra River is one of the largest rivers in Asia. It flows through Tibet, India, and Bangladesh. In northeastern India, it acts as a  natural barrier . Animals on the north side often evolve separately from animals on the south side. This is exactly what happened with  Ingerana  frogs. The northern species ( Ingerana borealis ) lives north of the river. The newly discovered southern species ( Ingerana occidens ) lives south of the river. Over thousands or millions of years, the river prevented them from interbreeding. So they became two different species.

Name Meaning: ‘Occidens’ for ‘West’

The species name  occidens  is derived from the  Latin word for ‘west’  . Why was this name chosen? Because the frog’s habitat marks the  westernmost known range  of any species in its genus. The genus  Ingerana  is found in parts of South and Southeast Asia. This new species is the furthest west. So the name is a tribute to its geographical position.

A Human Touch: The Researcher’s Excitement

Discovering a new species is a rare and thrilling experience. The researcher who found  Ingerana occidens  said, “When I saw the frog for the first time, I noticed its protruding eardrum and side stripe immediately. I knew it was different. But we had to wait for DNA results to be sure. When the report showed 18% difference, I jumped with joy.” This excitement is shared by all scientists who love exploring the natural world. Every new species is a reminder that our planet still holds secrets.

Why This Discovery Matters

Finding a new frog species is not just about adding a name to a list. It has real scientific importance:

• Understanding evolution:  The 18% genetic difference helps scientists understand how species split and evolve over time.

• Conservation:  Knowing that a species exists only in a small area helps conservationists protect its habitat.

• Biodiversity:  Each new species adds to our knowledge of the rich biodiversity of northeastern India. Meghalaya is part of the Indo-Burma biodiversity hotspot, one of the most biodiverse regions on Earth.

• River as barrier:  The discovery highlights the role of the Brahmaputra River as a natural divide. This can help predict where other undiscovered species might be found.

Threats and Conservation

The western trickle frog is newly discovered, so its population size is unknown. But its habitat – canopy-covered streams in Meghalaya – faces threats. These include:

• Deforestation  for mining, logging, and agriculture.

• Climate change  affecting rainfall and stream flow.

• Pollution  from nearby human settlements.

Scientists will now study the frog’s population and distribution. They will also recommend conservation measures if needed.

Comparison with Northern Relative

Conclusion

The discovery of  Ingerana occidens , the western trickle frog, is a wonderful addition to India’s amphibian fauna. Found in the Garo and Khasi Hills of Meghalaya, this tiny frog has smooth skin, a distinct side stripe, and protruding eardrums. Its DNA is 18% different from its northern relative, separated by the mighty Brahmaputra River. The name ‘occidens’ means ‘west’, reflecting its westernmost range. This discovery reminds us that even in well-studied areas, new species are waiting to be found. Protecting their forest stream habitats is essential.

Exam-Focused Points

• Species name:   Ingerana occidens  (common name: western trickle frog).

• Discovered in:  Garo and Khasi Hills, Meghalaya (northeastern India, south of Brahmaputra River).

• Genetic difference from  Ingerana borealis :  18% (confirms new species).

• Size:  Adult females up to 26 mm (small).

• Skin:  Mostly smooth with mild wrinkling (northern relative is heavily wrinkled).

• Distinct feature:  A contrasting stripe running down the side.

• Eardrum (tympanum):  Clearly visible, protruding, topped by a skin fold (northern species has invisible eardrums).

• Name meaning:  ‘occidens’ is Latin for ‘west’ – because it is the westernmost species of its genus.

• Habitat:  Canopy-covered streams.

• Geographical barrier:  Brahmaputra River separates it from the northern species.