Schizothorax plagiostomus

Schizothorax plagiostomus
Conservation status
Vulnerable  (IUCN 3.1) [1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Cypriniformes
Family:	Cyprinidae
Subfamily:	Schizothoracinae
Genus:	Schizothorax
Species:	S. plagiostomus
Binomial name
Schizothorax plagiostomus Heckel, 1838 [2]
Synonyms
Oreinus plagiostomus(Heckel, 1838) Schizothorax sinuatusHeckel, 1838 Oreinus sinuatus(Heckel, 1838) Oreinus griffithii McClelland, 1842

Schizothorax plagiostomus is a species of ray-finned fish in the family Cyprinidae. Common names include khont, snow trout, snow carp, snow barbel and swati fish. ^[3]

Description

Schizothorax plagiostomus has an elongated sub cylindrical body with short, blunt and slightly prognathous upper jaw. Ventral surface of head and anterior part of body flattish, short, somewhat cone shaped and blunt. Snout usually smooth covered with warys in male. Interorbital space broad and flat. Mouth inferior, wide and slightly arched; lips fleshy and continuous, marginally sharply attenuated, lower lip papillae and reflected from jaw, margin of lower lip sharp, covered with firm and hard horny cartilage; a strip of papillae labial plate at chin present. Barbless two pairs. Pharyngeal teeth in three rows. Dorsal fin inserted about opposite to pelvic fins, its last undivided ray osseous, strong and serrated posterior, short than head. Caudal fin deeply emarginated. Scales very small and elliptical; lipids irregular.

In the almost similar appearance of schizothorancine fishes, S. plagiostomus can be separated by its short, deep cornified lower jaw, with a transverse or sometimes only slightly curved sharp cutting margin. The lower and upper lips are connected by a smooth rounded corner. The particular arrangement of lower jaw structure was referred to as "sector mouth".

It weighs up to 2.5 kg and reaches 60 cm in length. It is sexually mature at 18–24 cm length and spawns in natural and artificial environments in two seasons, September–October and March–April. It spawns naturally in clear water on a gravelly or fine pebbled bed at 10–30 cm depth. Water current of 2.8–4 m/s, pH 7.5, dissolved oxygen concentrations Of 10–15 mg/L and gravel size of 50–60 mm are the optimum conditions for spawning. Raizada (1985)

Distribution

Schizothorax plagiostomus is found in different rivers, and tributaries throughout Himalaya extending to China, Afghanistan, Pakistan, Turkistan, Nepal, Ladkah, Tibet, Bhutan and north-eastern India (Day, 1958). In India, it is the most important food fish of the Himalayan region, including Kashmir, Himachal Pradesh, Uttarakhand, the Uttar Pradesh foothills and Assam (Day, 1958). It also plays an important role in commercial fish production (Bahuguna, 2002). From the subfamily Schizothorancinae 12 species are reported from Pakistan. The schizothoracine fishes provide a good material to study patterns of evolutionary modifications in terms of their biogeographic distribution. These species are expert in fast running high-elevation streams and rivers and show remarkable fitness for their environment.

References

1. Jan, A. & Daniels, A. (2022). "Schizothorax plagiostomus". IUCN Red List of Threatened Species . 2022 e.T128725859A139131270. doi: 10.2305/IUCN.UK.2022-1.RLTS.T128725859A139131270.en . Retrieved 5 January 2025.
2. Froese, Rainer; Pauly, Daniel (eds.). "Schizothorax plagiostomus". FishBase .
3. 7. Arif Jan., Rab, A., Ullah, R, Haroon, and Ullah, I. (2017). On the Breeding Season of Schizothorax plagiostomus. Pakistan J. Zool., vol. 49(2), pp 1-3.