In the early 2010s, taxonomist Balaji Vijayakrishnan was stationed in Rudrapur, Uttarakhand, where he worked for a private company. Every weekend, he would pack a net, and some bags and leave on an impromptu fishing trip to remote locations along the Ganga river.

Over three years, Vijayakrishnan amassed more than 300 specimens, amounting to roughly 30-40 species of loaches, catfishes and barbs. When he shifted base to Mumbai, the entire collection of specimens was sent to his parents’ residence in Chennai.

But in a cruel twist of fate, the Chennai floods of 2015 wiped out a majority of Vijayakrishnan’s collection. Stored in containers of formaldehyde and ethanol, the specimens were arranged in the basement parking of the house. Floods in 2016 further reduced the collection to zero specimens. “I don’t know if I can ever get back that collection,” Vijayakrishnan said.

Over the last decade, through annual visits, sometimes two-three trips a year, the independent researcher has been able to retrieve (in a sense) about 10% of the original collection. Most species were catfishes of the genus Glyptothorax and loaches of the genus Schistura.

In March this year, the self-taught taxonomist, along with another researcher Gaurav Anil Shinde, published a in the journal Zootaxa, describing two new species and...