Nasikabatrachus sahyadrensis is a frog species belonging to the family Sooglossidae. It can be found in the Western Ghats in India. Common names for this species are Purple Frog, Indian Purple Frog, Pignose Frog or Doughnut Frog. It was discovered by S.D. Bijuand F. Bossyut in October 2003 and was found to be unique for the geographic region.
With its closest relatives in the Seychelles, the Nasikabatrachus is thought to have evolved separately for millennia. Its discovery also adds to the evidence that Madagascar and the Seychelles separated from the Indian landmass sometime well after the breakup of Gondwanalandhad started. Owing to its ancient lineage, the purple frog has also been called "the coelacanth of frogs".
The body of ''Nasikabatrachus sahyadrensis'' is shaped similarly to that of most [frogs], but is somewhat rounded compared to other more dorsoventrally-flattened frogs. Its arms and legs splay out in the standard [Anura|anuran] body form. Compared to other frogs, ''N. sahyadrensis'' has a small head and an unusual pointed snout. Adults are typically dark [[purple]] in color. The [Holotype|specimen] with which the species was originally described was seven centimeters long from the tip of the [snout] to the tip of the [[urostyle]]. Also, its cry sounds more like one from a [chicken].
The species was discovered in the Idukki district of Kerala by S.D. Biju from the Tropical Botanic Garden and Research Institute in Palode, India and Franky Bossuyt from the Vrije Universiteit Brussel (Free University of Brussels). However it was well known to the local people before and several earlier specimens had been ignored.
Earlier thought to be restricted to the Western Ghats south of the Palghat gap, new records have extended its known range further north of the gap.
The frog spends most of the year underground, surfacing only for about two weeks, during the monsoon, for purposes of mating. The frog's reclusive lifestyle is what caused the species to escape earlier notice by biologists.
Unlike many other burrowing species of frogs that emerge and feed above the ground, this species has been found to forage underground feeding mainly on termites using their tongue and a special buccal groove. They show inguinal amplexus when mating afloat in temporary rainwater pools.
The scientific name derives from the Sanskrit word nasika (nose) referring to the pointed snout, batrachus Greek for frog, and Sahyadri as the local name of the mountain range where it was found - the Western Ghats.
The frog is a living fossil and was initially assigned to a new family of its own, Nasikabatrachidae, but has been more recently assigned to the family Sooglossidae which is found on the Seychelles islands.
Being a member of the family Sooglossidae, the species' origins lie in close consort with the Seychelles islands where the family was previously solely known from. The origin of the disjunct distribution goes back to about 100 million years ago, during which time India, the Seychelles and Madagascar formed a single landmass which split due to continental drift.