Nature Quest: Rare frog spotted

A rare species of frog was spotted and identified for the first time in Bangladesh during a series of surveys carried out in areas of mixed evergreen forest along the Karnaphuli river of Chittagong Hill Tracts between 2016 and early this year.

The name of the species is Gerbils stream frog.

An explorer team of the River and Life Quest programme, led by Kabir Bin Anwar, team leader and director general at the Prime Minister's Office, recorded the new species of frog from a hill stream of mixed evergreen forest in Barkal reserve forest of Rangamati.

The author of this report along with researchers Rajib, Hossain Sohel, Fazle Rabbi and Shakil Aronnoyo located the live and camouflaged specimen from a steep rocky hill stream of Barkal forest on January 16 this year. Detailed features of the specimen, and morphometric and habitat composition were recorded in both video and still forms.

After comprehensive literature review and taxonomic research on the specimen, this writer identified the species as Amolops gerbillus (Anaandale 1912). It belongs to family Ranidae of the class Amphibia. The common English synonyms are Gerbil stream frog, small-eared torrent frog and Yembung sucker frog. The frog has large and prominent barred discs in forelimbs, smaller in hind toe tips. Its skin is highly granular with dark brick blotches engraved on green back, and the ventral part is white.

Anisuzzaman Khan catching the rare frog at a forest in Rangamati on January 16. Photo Courtesy: Ekattor Television

This beautiful stream frog is found and distributed in the high gradient, torrent hill streams of Myanmar and India. It is native to northern and north-eastern India, Tibet (China), and Myanmar. This species has been recorded only from Dihang-Dibang Biosphere Reserve and Mouling National Park in India's Arunachal Pradesh. It is associated with streams and riparian vegetation within tropical evergreen forest. It exclusively occurs on boulders and bedrock in and along fast-flowing, clear-water forest streams, from lowlands to highlands. Breeding takes place in streams. There is little available information on egg deposition or larval ecology. After its discovery here, Bangladesh becomes a new geographical range of occurrence of the species. More research is required on the species' taxonomy, population status, life history and ecology.

[Anisuzzaman Khan is the chief consultant of River and Life Quest programme]