Shrimp species rediscovered in Karnataka and Odisha after 72 years

These shrimp are filter feeders, using fan-like structures on their limbs to filter out particles of edible material from flowing water, and are relatively well known within the aquarium hobby, being previously found across many locations in Southeast Asia.

According to the researchers, the new search for the shrimp began in 2022, after an Odisha-based aquarium hobbyist found a mature member of the species. However, they could not obtain it for study, and it died in captivity. They then had to narrow down the location.

The researchers noted that the search in Karnataka was particularly challenging, as the previous discoveries had been in Odisha. As the species is amphidromous (the larvae develop in brackish water before returning to freshwater), the researchers focused on areas where the brackish waterways had sandy beds with leaf litter and driftwood, with mangroves on the banks. For two years, until the specimens were found, searches were done across Udupi, Karwar, and Mangaluru employing various methods.

While the original discovery 72 years ago had identified the shrimp as a different species in the same genus (Atyopsis mollucensis), it seems that this may have been a misidentification. The researchers noted that all of the specimens they had recovered belonged to the species spinipes, including a museum specimen from the Andaman Islands. They noted that this species, unlike mollucensis, has larvae with higher tolerance for salt and temperature changes, enabling it to spread widely.

The team said in a statement that there was “an urgent need for systematic surveys and genetic validation to avoid misidentifications that can hinder conservation planning… the rediscovery indicates that many species may still remain undocumented in India’s freshwater ecosystems at a time when rivers, lakes, and streams are increasingly threatened by bridge construction, sand mining, and other human disturbances.”

But apart from the general threats to the shrimp population, the team noted that the aquarium trade could pose a problem in the absence of proper awareness and management. While these shrimp are sold at prices ranging between Rs 350-600, they cannot easily be bred in captive conditions, unlike many other shrimps popular in the aquarium hobby.