They dwell in moss and forest leaf litter.

Two scientists from the Zoological Survey of India, Bhaskar Saikia and Bikramjit Sinha, have found three new species of frogs from Tale Valley wildlife sanctuary in Arunachal Pradesh.

The discovery of Liurana Indica, Liurana Himalayana and Liurana minuta species has been reported in the journal Records of Zoological Survey of India.

The species were found during the faunistic surveys in the sanctuary, located in central Arunachal Pradesh (2015-18) when a number of amphibians were collected by one of the authors along with five specimens of small-sized moss and leaf litter dwelling frogs belonging to the genus Liurana.

Liurana Himalayana Pictures courtesy: Bikramjit Sinha

They were identified for their small size, absence of toe webbings, slightly enlarged toe pads but no disks and grooves on finger and the toe tip not was not clearly differentiated.

The scientists say the moss and leaf litter dwelling small frog group under genus Liurana are represented by only four species, all described from China; of which L. medogensis is known to occur in India. In recent years, surveys into Tale Valley wildlife sanctuary have revealed the occurrence of L. medogensis along with three hitherto unknown species of this genus from the protected area after a thorough morphological study of these specimen leads to them being identified as un-described species of Liurana.

“They are tiny and due to their habitat, very hard to spot in the forest. Previously only four species of Liurana frogs were known. Now with these three new species, the total is seven species for this genus of frog,” the scientists stated in the paper.

They were found at altitudes of 1,798-2,457 metres above sea level. “The habitat is moss and forest leaf litter,” the paper said.

Liurana Indica Pictures courtesy: Bikramjit Sinha

The suggested common English name for Liurana himalayana is Himalayan papilla-tongued frog.

The suggested common name for Liurana indica is Indian papilla-tongued frog and was found from an area displaying a transition zone between tropical evergreen forest and temperate forest.

The suggested common name for Liurana minuta is Minute papilla-tongued frog and was found from a river bank having rich growth of moss in tropical moist evergreen forest on the south-western fringe areas of Tale Valley wildlife sanctuary.

“The finding of the species provides an excellent clue that the southern slopes of the eastern Himalayas in Aruanchal Pradesh harbours suitable habitats for this moss and litter dwelling small frog group,” the paper said.