The purple frog (Nasikabatrachus sahyadrensis) is currently listed as the world’s 4th most Evolutionarily distinct and globally endangered amphibian species. This unusual frog has a limited distribution, confined to the Western Ghats mountain range in India. For the first time, video footage of the mating behaviour of this species has been released, airing as part of the Life Force-2 series on NHNZ and the Discovery Channel.
Video link: Https://vimeo.com/107249585
The video documents the emergence of purple frogs from their underground burrows during the monsoon season, in which males and females come together to reproduce in ponds and ditches. Males are significantly smaller than females, and climb on and attach to the backs of females in a mating embrace termed ‘amplexus.’ This grip may be maintained with the aid of sticky skin secretions, as occurs in “short-headed frogs” in the family Brevicipitidae.
Once eggs have been fertilized and laid in pools, males detach themselves from the females and both head back to the main river channel. For the rest of the year these frogs remain buried deep underground, using their pointed snouts to hunt termites. Their legs feature hard white ridges which are an adaptation to burrowing in the soil, normally to depths of 1.3-3.7 metres. In India, the purple frog may in fact be the only known amphibian species that is a fully underground forager; other burrowing frogs are either open burrow feeders or diurnal burrow dwellers that are open ground feeders in the night.
The species is part of the Sooglossidae amphibian family, and is thought to have evolved 135 million years ago, a time when dinosaurs were still roaming the earth. The closest relatives of the purple frog are four tiny frog species found in the Seychelles, also belonging to the Sooglossidae family. These species are being studied by EDGE fellow James Mougal (https://www.edgeofexistence.org/community/member_info.php?id=219) The purple frog is currently listed as Endangered on the IUCN Red List, and is threatened by the loss of its forest habitat in order to make way for coffee, cardamom and ginger plantations. The exact number of individuals left in the wild is unknown, but it is considered to be extremely rare, with only 135 individuals observed so far. This species does not occur in any protected areas and is therefore in desperate need of conservation attention.
For more information on this incredible species visit our purple frog species account page at https://www.edgeofexistence.org/amphibians/species_info.php?id=549
