A team of scientists from Delhi has discovered seven new frog species, four of which are so small that they can perch on a coin or a human fingernail. Found in the Western Ghats in Kerala and Tamil Nadu, these are among the smallest-known frogs on earth. All the new species are known as night frogs, and belong to the genus Nyctibatrachus. Night frogs are an ancient group of frogs endemic to the Western Ghats, which diversified approximately 70 to 80 million years ago. The discovery brings the total number of known night frogs to 35. Four of these are among the smallest Indian frogs, and measure between 12.2 to 13.3 mm in length.
They are as small as a five-year-old child’s thumbnail; and leap out of their daytime hideouts after sundown to croak to life the Western Ghat jungles with their signature cricket-like chirps. They are among seven new species of frogs, some of the tiniest in the world that were discovered by Indian scientists. These nocturnal amphibians measure between 12.2mm and 15.4mm. The discovery makes the rich but eco-sensitive Ghats the second-largest global amphibian hotspot after Brazil’s Atlantic Forest, a research paper reported on 21 February 2017. Named after the place of discovery such as Sabarimala and Athirappilly in Kerala, the paper said they were found inside “damp tree leaf litter or marsh vegetation” — unlike night frogs that predominantly reside along streams. That was a probable reason why these elusive frogs were out of sight until the 21st century.
The miniature species are locally abundant and fairly common, but they have probably been overlooked because of their extremely small size, secretive habits and insect-like calls,” said Delhi University research scholar Sonali Garg, the paper’s lead author. Locals knew about these frogs, but never thought they make sounds like crickets, explained SD Biju, a Delhi University taxonomy professor who guided the five-year research.