Scientists have discovered 12 new species of night frogs in western India.

The research also led to the rediscovery of three frog species thought to have been extinct. Two had not been seen in 75 years, while the third had gone unseen for 91 years.

Biologist SD Biju who led the research says amphibians are important barometers of environmental health. He said the precarious habitats of the newly discovered frogs need conservation support. Biju said amphibians are the most threatened species on Earth.

India is home to nearly 300 varieties of frogs.

Night frogs are especially hard to find as they come out only after dark.

The research on the new frog species is published in the latest issue of international taxonomy journal Zootaxa.