Port Blair, Nov. 13: A team of Scientists and researchers from Zoological Survey of India, Andaman and Nicobar Regional Centre, Port Blair in collaboration with University of Delhi, have discovered a genus of tree frog from Andaman Islands and the northeast.  The new genus Rohanixalusis named after the Sri Lankan taxonomist Rohan Pethiyagoda.

Dr. Chandrakasan Sivaperuman, Joint Director informed that this is the first time a tree frog species, Rohanixalus vittatus (Striped Bubble-nest Frog), is reported from the Andaman Islands. Even though the amphibian fauna of Andamans has been frequently surveyed in the recent years, this frog was so far not reported, despite being commonly found in wayside areas of North and Middle Andaman Islands. New findings of this frog, indicate that the amphibian inventory of the region is still far from being complete.

The scientists studied various aspects, such as the external morphology of adults & tadpoles, phylogeny, calls, and breeding biology of several tree frog species widely distributed across South, Southeast, and East Asia and confirmed that they represent a new genus. Frogs of this genus are known to inhabit forested as well as human-dominated landscapes right from Andaman Islands, Northeast India, Myanmar, Thailand, Malaysia, Indonesia, Vietnam, Laos, and Cambodia, up to southern China. Rohanixalus is the 20th recognized genus of the family Rhacophoridae and currently comprises eight out of the 422 known Old World tree frog species found in Asia and Africa.

Frogs of the new genus are characterized by a rather small and slender body (size about 2 to 3 cm long), a pair of contrastingly colored lateral lines on either side of the body, minute brown speckles scattered throughout the upper body surfaces, light green colored eggs laid in arboreal bubble-nests, and several unique behavioral traits including maternal egg attendance. Based on DNA studies, the new genus is also revealed to be a distinct evolutionary lineage from all previously known tree frog genera. During the breeding season, these tiny reddish-brown frogs can be found in large aggregations on bushes and shrubs (about 1 to 4 meters high) surrounding water bodies. Scientists believe that many more unnamed Rohanixalus species are likely to be present and future dedicated efforts are required to fully understand the existing species diversity in this new genus.

The findings are published in a scientific article titled ‘New insights on the systematics and reproductive behaviour in tree frogs of the genus Feihyla, with description of a new related genus from Asia (Anura, Rhacophoridae)’ in the current issue (12 November 2020) of Zootaxa, https://www.mapress.com/j/zt/article/view/zootaxa.4878.1.1  an international journal of animal systematics.

About the authors:


D. Biju: Professor and Researcher at University of Delhi. He has discovered and formally described 98 new species, 10 new genera, and two new families of amphibians from India and neighboring countries.

Sonali Garg: Post doctoral Research Associate at University of Delhi. She is a student of Prof. Biju and the only Indian women to have described 40 new species and three new genera of frogs.

Gokulakrishnan G: Research Associate at Zoological Survey of India, Andaman & Nicobar Regional Center.

Sivaperuman Chandrakasan: Officer-in-Change at Zoological Survey of India, Andaman & Nicobar Regional Center. He conducting faunal survey in this region.

Gopika C: PhD student at University of Delhi.

Karan Bisht: PhD student at University of Delhi.

Yogesh Shouche: Scientist at National Centre for Cell Science, Pune, Maharashtra, India.


Amir Hamidy: Scientist at Museum Zoologicum Bogoriense, Indonesian Institute of Sciences, Java, Indonesia.


Jinlong Ren: PhD student at Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China.


Panupong Thammachoti: Faculty member at Department of Biology, Chulalongkorn University, Bangkok, Thailand.