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EveryFish
Rohtee cotio var. alfrediana = Osteobrama alfredianus (Valenciennes, 1844)

Cotio

Small river fish of the Ganges and Brahmaputra basins

Photo: Sir Francis Day, Public domain, via Wikimedia Commons

Cotio is a small ray-finned fish native to the river systems of northern India and Bangladesh. It lives in slow-moving waters and feeds on insects, helping to control mosquito populations. Habitat loss from pollution and deforestation threatens its survival in the wild.

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  • Found in Ganges and Brahmaputra basins
  • Feeds on insects and mosquito larvae
  • Threatened by pollution and deforestation
  • Former subspecies are now separate species

What it is

Cotio is a species of ray-finned fish belonging to the genus Osteobrama. It was previously classified with three subspecies, but these are now recognised as distinct species. The fish inhabits freshwater environments such as rivers, lakes, ponds and ditches. Its body shape and colouration are typical of small cyprinids found in South Asian inland waters.

Where it lives

This fish is found in the drainage basins of the Ganges and Brahmaputra rivers. Specific locations include the Jiri River in Manipur and the Barak River in Silchar. It is present in Assam, Bihar, Madhya Pradesh, Uttar Pradesh and Punjab in India, as well as in Bangladesh. Reports of its presence in southern India and the Indus basin require further confirmation.

How it lives

Adults live in various still and slow-moving freshwater bodies. They have a largely insectivorous diet, feeding on insects found on or near the water surface. This feeding behaviour means they may help control populations of mosquito larvae in their habitat. They share their environment with other small freshwater fish in the region.

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

Status and threats

The species faces threats from extensive habitat loss. Pollution and deforestation in its range degrade the water quality and reduce available living space. These environmental pressures impact the stability of local populations across the Ganges and Brahmaputra basins.

Questions people ask about Cotio

Where does the Cotio fish live?

It lives in the freshwater drainage basins of the Ganges and Brahmaputra rivers. You can find it in India and Bangladesh, specifically in states like Assam, Bihar and Manipur.

What does the Cotio eat?

This fish has an insectivorous diet. It feeds mainly on insects, which means it helps control mosquito larvae in the ponds, ditches and rivers where it lives.

Is the Cotio endangered?

The species is threatened by extensive habitat loss. Pollution and deforestation in its native range are the primary causes of this decline, though a specific conservation status is not listed here.

Good reading and sources

Where this page comes from

The facts on this page come from the Wikipedia article "Osteobrama cotio", 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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