Bizarre burrowing purple frog found

Mysterious creature hails from time of Gondwanaland

October 17, 2003

In the verdant countryside of western India along the Arabian Sea, villagers digging a well in a cardamom plantation five years ago were astonished to spot a squat, bulbous purple frog sitting immobile nearly seven feet down in the mud.

The well-diggers turned their strange amphibian over to S.D. Biju, a visiting biologist who happened to be in the neighborhood from the Tropical Research Institute at nearby Thiruvananthapuram, the capital of the Indian state of Kerala. Biju was equally surprised.

Neither he nor any of his colleagues had ever seen a frog quite like it. With a pointed snout, glistening deep purple skin, red eyes and a powerful talent for burrowing into the ground, it looked like something primitive. Indeed it was.

The frog, it turned out, was a member of a totally unknown species of a totally unknown genus of a totally unknown family of frogs -- until now an undiscovered member of a wider tribe of "advanced frogs" that are known to number more than 4,800 species.

The family appears to date back more than 200 million years to a time when Africa and India were joined in a single vast supercontinent now called Gondwanaland. By 150 million years ago that continent had broken up into chunks of land masses that included Madagascar, the Seychelles, and the western Ghats of India.

When scientists discover a single new species of any animal it's normally cause for rejoicing; discovering an entirely new genus calls for drinks all around the laboratory, but discovering a whole new family with its subordinate genus and species can make a career.

This new one has been given the formidable name of Nasikabatrachus sahydrensis, a member of the new family called the Nasikabatrachidae. Nasika is Sanskrit for nose; batrachus means frog, and the species name, sahydrensis, refers to the Western Ghats, the hills along India's west coast where the frog lives, Biju explained.

Franky Bossuyt, an evolutionary geneticist at the Brussels Free University in Belgium, looked at the frog's DNA for clues about its evolution. He concluded that about 100 million years ago, the Nasikabatrachidae family split off from earlier members of the frog lineage.

News of the frog discovery by Biju and the DNA analysis by Bossuyt are published this week in the journal Nature and are already causing an international stir.

"I'm absolutely amazed,'' exclaimed Robert Drewes, chairman and curator of herpetology at the California Academy of Sciences in San Francisco, who has researched frogs and their evolution in 28 African countries for the past 30 years. "This is really fantastic; it's weird stuff."