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EveryFish
India, Shillong, by Ben Laloo

Copper mahseer

A freshwater cyprinid fish native to South and Southeast Asia.

Photo: Ben Laloo, CC BY 3.0, via Wikimedia Commons

The copper mahseer is a ray-finned fish in the carp family. It inhabits rivers across Nepal, India, Bangladesh, Myanmar, Thailand, Malaysia and Sumatra. Authorities classify it as endangered due to population declines. Sikkim adopted it as its state fish in 2021.

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  • Sikkim declared it the state fish in 2021.
  • IUCN listed it as endangered in 2014.
  • It lives in the Teesta and Rangit rivers.
  • Records from China and Viet Nam are uncertain.

What it is

This ray-finned fish belongs to the Cyprinidae family, which contains carps and barbs. It goes by several names, including chocolate mahseer and katli. The animal lives in fresh water rather than salt water. Its body shape and colouring suit river environments. Scientists identify it by its specific taxonomic classification within the genus Neolissochilus.

Where it lives

Populations exist in Nepal, eastern India, Bangladesh, Myanmar, Thailand, Malaysia and Sumatra. Records from China and Viet Nam remain uncertain and might represent misidentifications. Within India, the fish occupies various altitudes in Sikkim. It swims mainly in the Teesta and Rangit rivers along with their tributary streams. These waterways provide the necessary habitat for the species.

Copper mahseer
A drawing made by EveryFish from what this page says. It is a diagram, not a picture of the real fish.

Fish and people

Local communities in Sikkim call this fish Katley. In 2021, the state government declared it the official state fish. This designation highlights its cultural importance to the region. People recognise it as a distinct part of their natural heritage. The name katli is also used in other areas where the fish is found.

Status and threats

The National Bureau of Fish Genetic Resources in Lucknow listed the species as endangered in 1992. The International Union for Conservation of Nature confirmed this status in 2014. These classifications indicate that the population faces significant threats. Conservation efforts aim to protect the remaining groups in their native rivers. The uncertain records in the eastern range complicate protection strategies.

Questions people ask about Copper mahseer

Where does the copper mahseer live?

It inhabits freshwater rivers in Nepal, eastern India, Bangladesh, Myanmar, Thailand, Malaysia and Sumatra. In Sikkim, it is found in the Teesta and Rangit rivers.

Is the copper mahseer endangered?

Yes. The IUCN categorised it as endangered in 2014. Indian authorities had already listed it as endangered in 1992.

What is the local name for this fish in Sikkim?

In Sikkim, locals call the fish Katley. It was declared the state fish there in 2021.

Good reading and sources

Where this page comes from

The facts on this page come from the Wikipedia article "Neolissochilus hexagonolepis", written by its contributors and used under the CC BY-SA 4.0 licence, and from its Wikidata record (CC0). EveryFish rewrote the text in its own words, with AI assistance, and compares every page with the article to make sure no passage is copied. It may be reused under the same CC BY-SA 4.0 licence with a link back.

It may contain mistakes, and figures change over time. Nothing here is investment or buying advice. If something is wrong, tell us. Last refreshed 2026-11-15.

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Photo credits on this page

The small pictures above come from Wikimedia Commons under free licences. Some are cropped to fit.

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