This hitherto unknown behavior was documented in the remote Kalakad Mundanthurai Tiger Reserve in the Western Ghats by Seshadri K S, a PhD student at National University of Singapore; his thesis advisor David Bickford and collaborator Gururaja K V from the Indian Institute of Science, Bangalore, says a Gubbi Labs release.
The frog enters hollow, living bamboo stems via small openings and deposits eggs, which hatch directly into froglets. Adult frogs then stay with the eggs and young froglets, providing parental care.
It was thought to be extinct for over a century until it was re-discovered a few years ago by a team of scientists working in the remote Kalakad Mundanthurai Tiger Reserve. It is currently listed as "Critically Endangered" by the International Union on Conservation of Nature and Natural Resources (IUCN).
Adult males start vocalising early in the evening and they enter bamboo via a small opening, which is usually less than 5-10 mm long and 3-4 mm wide. They continue to call from inside the bamboo. The female follows the male inside and then lays 6-7 eggs inside. These eggs directly develop into froglets; there is no tadpole stage in these frogs.