Researchers at IIT Bombay discover the role of environmental resources, genes and mating in species in the development of new species in the same area, challenging the traditional view that new species can develop only in distinct geographies.

A new species of narrow-mouthed frog discovered in the Western Ghats

Read time: 1 min
19 Dec 2018
Photo: Microhyla darreli by S. D. Biju

In a recent study, researchers have reported the discovery of yet another species of frog in the Western Ghats of Kerala. This species, named Microhyla darreli belongs to the genus Microhyla, commonly known as narrow-mouthed frogs because of their triangular-shaped body and pointed snout. The frogs of this genus are widely distributed through Japan, China, India, Sri Lanka and Southeast Asia.

The new frog species was unearthed when the researchers were doing a comprehensive taxonomic revision of frogs of the genus Microhyla from South Asia. The team consisted of researchers from India, Sri Lanka, China, Indonesia and USA. The Indian institutes included the University of Delhi, Wildlife Institute of India (WII), Mangalore University and the Ashoka Trust for Research in Ecology and the Environment (ATREE). This study was published as a monograph in the journal Vertebrate Zoology. It was partly funded by the University of Delhi, Council for Scientific and Industrial Research (CSIR) and the Department of Science and Technology (DST).

The species was confirmed to be previously unknown after using an integrated taxonomic approach, where the researchers compared the DNA, physical characteristics, and calls of this frog with other similar species in the genus. Microhyla darreli, or Darrel’s chorus frog, was named after the American herpetologist Dr Darrel R. Frost, in recognition of his work the Amphibian Species of the World, an Online Reference. This online database maintains a taxonomic catalogue of all the known amphibians of the world.

Individuals of M. darreli are similar to many other species in the same genus. Their call is also identical to M. zeylanica, a narrow-mouthed frog endemic to Sri Lanka. The researchers further found that M. darreli has a short breeding season, during the monsoon months of June-July. “In the months of June-July, a large number of individuals were observed inside a wayside plantation area at a rural settlement close to the Karamana River”, say the authors.

M. darreli is currently known only from the Western Ghats of Kerala, and its range overlaps with M. ornata or Ornate narrow-mouthed frog, which is found in South Asia.

“The two were also observed calling alternatively at the same site. Calling males of M. darreli were usually observed hiding under leaf litter or ground vegetation, while males of M. ornata were relatively more exposed”, say the authors.

The discovery of the new frog species takes the total number of narrow-mouthed frogs known so far to 45. With scientists equipped with improved taxonomic methods and new interest in amphibians, we can hope to uncover more such novel findings in the coming years.