Rare Tibetan Fish Recorded in India for First Time From Arunachal’s High-Altitude Lake

Scientists have recorded the high-altitude fish Schizopygopsis waddellii in India for the first time, after specimens were collected from Pangkang Teng Tso Lake in Tawang district of Arunachal Pradesh.

Researchers from the ICAR–Central Institute of Coldwater Fisheries Research (ICAR-CICFR), Bhimtal, collected ten specimens from the natural alpine lake in July 2026. The lake lies at an elevation of about 12,800 feet above mean sea level, close to India’s eastern Himalayan frontier. The finding was reported in early September and has drawn wider attention on September 11.

The identification was not based on appearance alone. Researchers examined the fishes’ physical characteristics and then used mitochondrial DNA analysis to confirm their identity. This combination of morphological and molecular evidence is particularly useful in Himalayan fishes, where closely related species can be difficult to distinguish by external features alone.

The work involved ICAR-CICFR along with the Department of Fisheries, Government of Arunachal Pradesh, and the Shar-Tso Committee.

A Fish Previously Associated With Tibet

Schizopygopsis waddellii belongs to the family Cyprinidae, which includes carps and many other freshwater fishes. It is part of a group adapted to the cold, oxygen-poor and highly seasonal waters of the Tibetan Plateau and adjoining Himalayan region.

Until the Arunachal Pradesh record, the species was known from the Tibetan Plateau in China. Its type specimens came from Yamdok Lake in Tibet, where the species was described by British ichthyologist Charles Tate Regan in 1905. Eschmeyer’s Catalog of Fishes continues to list Tibet, China, as its established distribution.

Finding the species in Tawang therefore extends its confirmed geographical range southward into India.

The record is also significant because Tawang’s high-altitude lakes lie within the same broad Himalayan and Tibetan ecological landscape. Mountain ranges and political borders divide the region administratively, but freshwater species can reflect much older geological and ecological connections between neighbouring high-altitude drainage systems.

Ten Specimens Confirm the Indian Record

The researchers collected ten specimens from Pangkang Teng Tso Lake during their July survey. According to ICAR-CICFR scientist Neetu Shahi, the finding suggests that other fishes currently recorded from the Chinese side of the high Himalayas could also occur in lakes on the Indian side.

That possibility is particularly relevant in Arunachal Pradesh, where many alpine lakes remain poorly surveyed for freshwater biodiversity.

Most biological surveys in the eastern Himalayas have historically concentrated on forests, mammals, birds and lower-altitude rivers. Remote lakes above 3,500 metres are considerably harder to reach and often receive much less systematic scientific attention.

The discovery of S. waddellii illustrates how surveys of such water bodies can change the known distribution of Himalayan species without the discovery necessarily involving an entirely new species.

Adapted to Extreme High-Altitude Conditions

Life in an alpine lake places unusual demands on freshwater fish. Water temperatures can remain extremely low for much of the year, food availability fluctuates sharply, and winter ice can cover lakes for prolonged periods.

Members of the Schizopygopsis group are specialised for these environments. They form part of the distinctive cold-water fish fauna that evolved across the Tibetan Plateau and surrounding mountains.

The Pangkang Teng Tso population could therefore provide researchers with an opportunity to compare Indian specimens with populations farther north and examine whether geographic isolation has produced genetic or morphological differences.

Further genetic sampling could also help establish how populations on opposite sides of the Himalayan watershed are related and how these fishes dispersed through the region in the past.

Arunachal’s Alpine Lakes Remain Poorly Explored

The record adds another species to India’s documented freshwater fish fauna, but its wider importance lies in what it suggests about the high-altitude lakes of Arunachal Pradesh.

Researchers involved in the finding have called for more systematic surveys, particularly in lakes close to the international frontier. Such work could reveal species whose known ranges currently end abruptly at political boundaries simply because equivalent habitats on the Indian side have not been studied in sufficient detail.

These ecosystems are also sensitive to environmental change. High-altitude lakes can respond quickly to shifts in temperature, snow cover, precipitation and tourism pressure. Establishing which species live in them is therefore an important first step towards monitoring future changes.

The discovery of Schizopygopsis waddellii at Pangkang Teng Tso does not merely add another name to India’s fish checklist. It provides evidence that the aquatic biodiversity of Arunachal Pradesh’s alpine lakes remains incompletely documented and that the eastern Himalayas may still contain important range extensions—and possibly undescribed freshwater diversity—waiting to be recorded.