In November 2025, Researchers from Wildlife Institute of India (WII), Dehradun achieved a landmark discovery by identifying 13 new bush frog species (genus Raorchestes) across Northeast India’s Eastern Himalayas and Indo-Burma biodiversity hotspot.
- Published on November 19, 2025 in Vertebrate Zoology (DOI: 10.3897/vz.75.e148133), the study analysed 204 specimens collected from 81 localities (2016-2024) spanning 8 states and 25 protected areas – India’s largest single vertebrate species description in over a decade.
Exam Hints:
- What? 13 new frog species are discovered
- Where? In the Northeastern States
- Studied by? Bitupan Boruah and Dr. Deepak Veerapan
- Significance? Highest no of species discovered in a single study
- Identified by? Wildlife Institute of India (WII)
- Species: R. Orientalis, R. Eaglenestensis, R. Magnus, R. Nasuta, R. Dibangensis, R. Dibangensis, R. Arunachalensis, R. Mawsynramensis, R. Boulengeri, R. narpuhensis, R. Barakensis, R. Lawngtalaiensis, R. khonoma, R. monolithus.
List of 13 New Species:
Arunachal Pradesh (6): R. orientalis (Eastern bush frog), R. eaglenestensis (Eaglenest bush frog, Eaglenest WLS 1,655m), R. magnus (large-bodied, SVL 25-30mm), R. nasuta (pointy-nosed snout), R. dibangensis (Dibang Valley bush frog), R. arunachalensis (Arunachal bush frog).
Meghalaya (3): R. mawsynramensis (Mawsynram bush frog), R. boulengeri (Boulenger’s bush frog), R. narpuhensis (Narpuh bush frog, Narpuh WLS).
Single Species: R. barakensis (Barak Valley bush frog, Barail WLS Assam), R. lawngtalaiensis (Lawngtlai bush frog, Ngengpui WLS Mizoram), R. khonoma (Khonoma bush frog, Nagaland), R. monolithus (Willong-Khullen bush frog, Manipur).
Physical Characteristics:
Size: Small-bodied (snout-vent length SVL 18-30mm); head wider than long.
Distinctive Features: No vomerine teeth; indistinct tympanum, prominent supratympanic fold; pyriform tongue notched posteriorly; finger discs with circum-marginal grooves (no webbing between fingers); rudimentary toe webbing; relative lengths: Fingers I<II<IV<III, Toes I<II<III<V<IV.
Sexual Dimorphism: Males have transparent gular pouch (visible during “tik-tik” calls), nuptial pads; inner palmar tubercle absent, outer present; tibiotarsal articulation reaches eye when leg stretched.
Coloration: Dorsal warts (6 posterior to eyes); pale/dark brown dorsum; direct development (eggs hatch as froglets, no tadpole stage).
Scientific Methodology :
Integrative Taxonomy: Mitochondrial DNA (16S rRNA), nuclear genes, morphology, bioacoustics (call variations); elevational range 235-1,655m; addressed 3 conservation shortfalls (Linnean/Wallacean/Darwinian).
Key Findings: Synonymised 4 species; first sub-Himalayan study; cryptic diversity in rainforest understory/shrub layers.
Lead Team: Bitupan Boruah (WII PhD), Dr Abhijit Das (WII), Dr Deepak Veerappan (Natural History Museum, London); Funding: National Geographic, Meghalaya Biodiversity Board.
Ecological and Conservation Significance:
Protected habitats: Several species were discovered in protected areas, offering partial safety and highlighting critical biodiversity zones.
Biodiversity importance: The study underscores Northeast India as a hotspot for amphibians and small vertebrates, reinforcing the need for sustainable forest and habitat management.
Largest discovery in a decade: This publication represents the highest number of vertebrate species described in India in a single study over the last ten years.
About Wildlife Institute of India (WII):
Director-Gobind Sagar Bhardwaj
Established– 1982
Headquarters- Dehradun, Uttarakhand
