A group of scientists from India, Sri Lanka and the US found the tadpole, which remained undiscovered because they live underground.
PLOS ONE journal recently published a study by Gayani Senevirathne from the University of Peradeniya and colleagues, detailing the discovery.
According to the study, the tadpoles burrow through the sand beds near streams, and live in total darkness until they fully develop into young frogs.
The Indian Dancing frogs are so-named because of the way they wave their legs in territorial and sexual displays while sitting on boulders in streams.
Though these "dance moves" are well known, the tadpoles of these frogs remained a complete mystery.
"We provided the first confirmed report of the tadpoles of Indian Dancing Frog family. These tadpoles probably remained unnoticed all these years because of their fossorial nature which in itself is a rare occurrence in the amphibian world," Prof S D Biju from the University of Delhi said in a statement.