Actinopterygii (ray-finned fishes) > Cypriniformes
(Carps) > Cyprinidae
(Minnows or carps) > Xenocyprinae
Etymology: Hypophthalmichthys: Greek, hypo = under + Greek, ophthalmos = eye + Greek, ichthys = fish (Ref. 45335); nobilis: nobilis, meaning noble (Ref. 10294).
Environment / Climate / Range
Freshwater; benthopelagic; potamodromous (Ref. 51243); depth range 5 - ? m. Temperate; 4°C - 26°C (Ref. 37797); 64°N - 18°S
Length at first maturity / Size / Weight / Age
Maturity: Lm 65.0, range 55 - 70 cm
Max length : 146 cm SL male/unsexed; (Ref. 59043); common length : 60.0 cm TL male/unsexed; (Ref. 2059); max. published weight: 40.0 kg (Ref. 59043); max. reported age: 20 years (Ref. 59043)
soft rays: 12 - 14. Body with numerous scattered small black blotches. Keels extend from pelvic base to anus. Barbels absent. Posterior margin of last simple dorsal ray not serrated. Branched anal rays 13-14.5 (Ref. 13274). Differs from Hypophthalmichthys molitrix by having scaled keel from pelvic to anal, 240-300 long gill rakes, head length 27-35% SL, dark overall coloration, flank with dark, large, very irregularly shaped blotches, fin bases and inferior parts of head and belly yellowish (Ref. 59043).
Asia: China. Introduced to numerous countries and has achieved a near global distribution. However, its breeding requirements are very specialized and stocks are maintained by artificial reproduction or continuous importation. Several countries report adverse ecological impact after introduction (Ref. 1739). Often confused with Hypophthalmichthys molitrix (Ref. 59043).
In its natural environment, it occurs in rivers with marked water-level fluctuations, overwinters in middle and lower stretches. Forages in shallow (0.5-1.5 m deep) and warm (over 24°C) backwaters, lakes and flooded areas with slow current. Breeds in very deep, very turbid and warm water above 18°C (usually 22-30°C), with high current (1.1-1.9 m/s) and high oxygen concentrations. Stocked to large rivers and almost all still water bodies as lakes and ponds. In aquaculture, adults can survive brackish water (up to 7 ppt) when released into estuaries and coastal lakes. Feeds mainly on zooplankton, but also takes algae as food (Ref. 59043). Bottom feeding fish (Ref. 6459). Undertakes long distance upriver migration at start of a rapid flood and water-level increase (in April-July depending on locality). Spawns in upper water layer or even at surface during floods. Spawning ceases if conditions change and resumes again when water level increases. After spawning, adults migrate for foraging habitats, Larvae drift downstream and settle in floodplain lakes, shallow shores and backwaters with little or no current. During autumn-winter, when temperature drops to 10°C, juveniles and adults form separate large schools and migrate downstream to deeper places in main course of river to overwinter (Ref. 59043). Marketed fresh and frozen.
Produces up to 100,000 eggs (Ref. 2059). Eggs are yellowish, transparent, and hatch after about 2 days at temperatures around 25°C while drifting downstream in the deep open-water layer (Ref. 59043).
Kottelat, M., 2001. Freshwater fishes of northern Vietnam. A preliminary check-list of the fishes known or expected to occur in northern Vietnam with comments on systematics and nomenclature. Environment and Social Development Unit, East Asia and Pacific Region. The World Bank. 123 p. (Ref. 44416)
IUCN Red List Status (Ref. 96402)
CITES (Ref. 94142)
Threat to humans
Fisheries: highly commercial; aquaculture: commercial; aquarium: public aquariums
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.6250 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01413 (0.01101 - 0.01813), b=3.04 (2.97 - 3.11), based on LWR estimates for this species (Ref. 93245
Trophic Level (Ref. 69278
): 2.8 ±0.33 se; Based on food items.
Resilience (Ref. 69278
): Medium, minimum population doubling time 1.4 - 4.4 years (tm=3-5; tmax=20; K=0.15-0.27; Fec=50,000-1 million).
Vulnerability (Ref. 59153
): High to very high vulnerability (66 of 100) .