Amur sturgeon

The Amur sturgeon or Japanese sturgeon (Sinosturio schrenckii) is a species of fish in the family Acipenseridae found in the Amur River basin in China and Russia. They migrate outwards to the Sea of Japan and the Sea of Okhotsk.^[5] The species has 11–16 dorsal, 34–47 lateral, and 7–16 ventral scutes. Their dorsal fins have 38–53 rays and 20–35 anal fin rays. They also have greyish-brown backs and pale ventral sides. The species can reach up to 3 metres (9.8 ft) in length, and weigh over 190 kilograms (420 lb).^[6] The species is considered to be critically endangered.^[1]

Japanese sturgeon
Conservation status
Critically Endangered  (IUCN 3.1)[1]
CITES Appendix II (CITES)[2]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Acipenseriformes
Family:	Acipenseridae
Genus:	Sinosturio
Species:	S. schrenckii
Binomial name
Sinosturio schrenckii (von Brandt, 1869)
Synonyms[3][4]
Acipenser baeri schrencki von Brandt 1869 Sturio schrenckii (von Brandt 1869) Acipenser multiscutatus Tanaka 1908

Prior to 2025, it was placed in the genus Acipenser. However, this placement was long known to be paraphyletic. In 2025, it was moved to the revived genus Sinosturio.^[5][7]

Habitat and ecology

The Japanese sturgeon is benthic. Their main food sources are aquatic insect larvae, bony fish and mollusks. One study suggests that the type of aquatic insect larvae eaten by juvenile Japanese sturgeon depends on the season, where mayfly nymphs are eaten more frequently in spring and fall, and midge larvae are eaten more frequently in summer.^[8] The females mature at 9–10 years of age, and males at 7–8 years. They start to migrate in the autumn. They live for 65 years.^[6]