Guwahati, Oct. 21 -- Monish Upadhyay

A decade ago, Wimarithy K. Marak, a resident of Assam's Goalpara district, often used to encounter a small pink creature in her neighbourhood's wells. She simply thought of it as a worm infesting her locality. In 2021, after she became a researcher, she stumbled upon the creature again while drawing water from a well. "This time I sent the picture to my supervisor and we brought a specimen to the lab," she says.

The creature turned out to be a two-centimetre long blind loach with a body so transparent that its blood and internal organs give it a striking blood-red appearance. The first specimen was collected in March 2021. Although further explorations into neighbouring wells yielded no results for t...