Indian scientists discover four new species of smallest known frogs from the Western Ghats

Indian scientists discover four new species of smallest known frogs from the Western Ghats NEW DELHI: Another big discovery from the "Frogman(ग़ोताख़ोर) of India", as professor SD Biju from Delhi University (DU) and his team discovered four new miniature(लघु)  species, now listed among the smallest known frogs in the world. The scientists were surprised by the relative abundance

(विपुलता) of these new miniature species. In all Biju's team have discovered seven new frog species belonging to the genus Nyctibatrachus, commonly known as Night Frogs. This find is a result of five years of extensive explorations(अन्वेषणों) in the Western Ghats global biodiversity(जैव विविधता)  hotspot in India. Four out of seven of the new species are miniature-sized frogs (12.2-15.4 mm), which can comfortably sit on a coin or a thumbnail. These are among the smallest known frogs in the world. Unlike other frogs in the genus that are predominantly stream dwelling, the new miniature frogs were found under damp forest leaf litter or marsh vegetation.  "In fact, the miniature species are locally abundant and fairly common but they have probably been overlooked because of their extremely small size, secretive habitats (आवासों)and insect(कीट)-like calls," said Sonali Garg, who undertook this study as part of her PhD research at DU.

In the lab, the newly sampled frogs were confirmed as new species by using an integrated taxonomic(वर्गीकरण)  approach that included DNA studies, detailed morphological comparisons and bioacoustics. Evidence from these multiple sources confirmed that the diversity of Night frogs is higher than previously known and particularly remarkably for the miniaturized forms. Previously, the Night Frog genus comprised of 28 recognized species of which only three were miniature-sized (<18mm) Now the total number of known Nyctibatrachus species has increased to 35, of which 20% are diminutive in size. This frog genus is endemic to the Western Ghats of India and represents an ancient group of frogs that diversified on the Indian landmass approximately 70-80 million years ago.

The discovery of several new species of ancient origin can provide useful insights into the evolution of endemic frog lineages in the Western Ghats, which is a leading amphibian hotspot. The past decade has witnessed an exponential increase in the number of new amphibian species described from this region. Of the total new species of amphibians (1581) described globally between the years 2006-2015, the highest number were from the Brazilian Atlantic Forest (approximately 182) followed by the Western Ghats-Sri Lanka biodiversity hotspot (approximately 159), with 103 species described alone from the Western Ghats region.