Why In News?

The rare cold-water fish Schizopygopsis waddellii was recorded for the first time in India from a high-altitude lake in Tawang, Arunachal Pradesh.

What is Schizopygopsis waddellii?

Schizopygopsis waddellii is a cold-adapted, freshwater fish species capable of surviving in near-freezing, low-oxygen high-altitude alpine aquatic environments.

Taxonomy

  • Belongs to the Schizothoracine subfamily (snowtrout group) within the Cyprinidae family (carps).

  • This subfamily is evolutionarily specialized for cold, torrential mountain waters, exhibiting streamlined bodies, reduced scales, and enhanced hydrodynamics for survival in high‑altitude ecosystems.

Morphological Adaptations

  • Vent and Anal Fin: Surrounded by a sheath of enlarged scales that aid in stability and maneuverability in strong alpine currents.

  • Feeding Mechanism: Subterminal mouth equipped for scraping epilithic algae and biofilm from submerged rocks.

  • Gill Modification: Enlarged lamellae and vascular structures maximize oxygen absorption in thin, low‑pressure mountain air.

  • Body Form: Elongated, sub‑cylindrical shape with a deeply forked caudal fin for rapid propulsion in icy streams.

Habitat

  • Earlier Range: Confined to Tibetan Plateau and China, mainly across the Yarlung Tsangpo (Brahmaputra) drainage basin and Yamdrok Lake.

  • New Indian Record: Discovered at Pangkang Teng Tso Lake, Tawang district, Arunachal Pradesh, at 12,800 ft elevation, marking its first confirmed presence in India.

Ecological Significance

  • Expands India’s freshwater ichthyofaunal diversity and strengthens trans‑Himalayan biogeographical linkages.

  • Serves as an indicator species for fragile alpine aquatic ecosystems vulnerable to climate change and glacial retreat.

Source: NEWSONAIR

PRACTICE QUESTION

Q. With reference to 'Schizopygopsis waddellii', recently seen in the news, consider the following statements:

1. It is a cold-water freshwater fish belonging to the subfamily Schizothoracinae (snowtrout).

2. It was recorded for the first time in India from a high-altitude natural lake in Arunachal Pradesh.

3. It is an invasive marine species that entered peninsular river systems through international cargo ship ballast water.

4. The species is physiologically adapted to withstand low-temperature and low-oxygen alpine aquatic environments.

Which of the statements given above are correct?

A) 1, 2, and 4 only

B) 2 and 3 only

C) 1 and 3 only

D) 1, 2, 3, and 4

Answer: A

Explanation:

Statement 1 is correct: Schizopygopsis waddellii (commonly known as Waddell's snowtrout) is a cold-adapted freshwater fish belonging to the family Cyprinidae and the snowtrout subfamily/group.  

Statement 2 is correct: Scientists from the ICAR-Central Institute of Coldwater Fisheries Research (ICAR-CICFR), alongside the Arunachal Pradesh Department of Fisheries, recorded the species for the first time in India from the Pangkang Teng Tso Lake (~12,800 feet elevation) in Tawang district, Arunachal Pradesh.  

Statement 3 is incorrect: It is not an invasive marine species introduced via ship ballast water. It is a high-altitude freshwater fish native to the Tibetan Plateau and adjacent Himalayan highlands.  

Statement 4 is correct: The species is physiologically and morphologically adapted to harsh, high-altitude alpine aquatic environments characterized by extreme cold and lower dissolved oxygen levels.