The Russian sturgeon (''Huso gueldenstaedtii''), also known as the diamond sturgeon or Danube sturgeon, is a species of

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

in the family

Acipenseridae Sturgeon (from Old English ultimately from Proto-Indo-European language, Proto-Indo-European *''str̥(Hx)yón''-) is the common name for the 27 species of fish belonging to the family Acipenseridae. The earliest sturgeon fossils date to the ...

. It is found in

Azerbaijan Azerbaijan, officially the Republic of Azerbaijan, is a Boundaries between the continents, transcontinental and landlocked country at the boundary of West Asia and Eastern Europe. It is a part of the South Caucasus region and is bounded by ...

Bulgaria Bulgaria, officially the Republic of Bulgaria, is a country in Southeast Europe. It is situated on the eastern portion of the Balkans directly south of the Danube river and west of the Black Sea. Bulgaria is bordered by Greece and Turkey t ...

Georgia Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of pe ...

Iran Iran, officially the Islamic Republic of Iran (IRI) and also known as Persia, is a country in West Asia. It borders Iraq to the west, Turkey, Azerbaijan, and Armenia to the northwest, the Caspian Sea to the north, Turkmenistan to the nort ...

Kazakhstan Kazakhstan, officially the Republic of Kazakhstan, is a landlocked country primarily in Central Asia, with a European Kazakhstan, small portion in Eastern Europe. It borders Russia to the Kazakhstan–Russia border, north and west, China to th ...

Romania Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...

Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...

Turkey Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...

Turkmenistan Turkmenistan is a landlocked country in Central Asia bordered by Kazakhstan to the northwest, Uzbekistan to the north, east and northeast, Afghanistan to the southeast, Iran to the south and southwest and the Caspian Sea to the west. Ash ...

, and

Ukraine Ukraine is a country in Eastern Europe. It is the List of European countries by area, second-largest country in Europe after Russia, which Russia–Ukraine border, borders it to the east and northeast. Ukraine also borders Belarus to the nor ...

. It is also found in the

Caspian Sea The Caspian Sea is the world's largest inland body of water, described as the List of lakes by area, world's largest lake and usually referred to as a full-fledged sea. An endorheic basin, it lies between Europe and Asia: east of the Caucasus, ...

. This fish can grow up to about and weigh . Russian sturgeon mature and reproduce slowly, making them highly vulnerable to fishing. It is distinguished from other '' Acipenser'' species by its short snout with a rounded tip as well as its lower lip which is interrupted at its center. Prior to 2025, it was placed in the genus '' Acipenser'', but this placement was found to be

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

, and it is more accurately placed in the genus ''

Huso ''Huso'' is a genus of sturgeons from eastern Europe, Asia, and eastern North America. The genus name is derived from ''wikt:huso, hūso'', the Old High German and Medieval Latin word for "sturgeon", which is also ancestral to ''wikt:Hausen, Haus ...

''.

Description

The Russian sturgeon can grow to but a more normal size is . It has a relatively short and rounded snout with three pairs of unfringed

barbels In fish anatomy and turtle anatomy, a barbel is a slender, whisker like sensory organ near the mouth (sometimes called whiskers or tendrils). Fish that have barbels include the catfish, the carp, the goatfish, the hagfish, the sturgeon, the z ...

closer to the tip of the snout that to the mouth. The dorsal fin has 27 to 48 soft rays and the anal fin has 16 to 35. The number of scales along the

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelia ...

varies from 21 to 50. This fish can be distinguish from the otherwise similar starry sturgeon by the shape of its snout, its barbels and scale arrangement. The upper surface is greyish-green, the lateral scales are pale and the belly white. Russian_sturgeon

Distribution and habitat

The Russian sturgeon is native to the

Black Sea The Black Sea is a marginal sea, marginal Mediterranean sea (oceanography), mediterranean sea lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bound ...

, the

Sea of Azov The Sea of Azov is an inland Continental shelf#Shelf seas, shelf sea in Eastern Europe connected to the Black Sea by the narrow (about ) Strait of Kerch, and sometimes regarded as a northern extension of the Black Sea. The sea is bounded by Ru ...

and the

. It is an anadromous fish and moves into the river systems that drain into these seas in order to make its way to spawning areas upstream. It is usually found near the bottom in fairly shallow water over sandy or muddy substrates.

Biology

The Russian sturgeon feeds on crustaceans, molluscs and small fishes such as

gobies Gobiidae or gobies is a family of bony fish in the order Gobiiformes, one of the largest fish families comprising over 2,000 species in more than 200 genera. Most of gobiid fish are relatively small, typically less than in length, and the fam ...

, anchovies and

sprat Sprat is the common name applied to a group of forage fish belonging to the genus ''Sprattus'' in the Family (biology), family Clupeidae. The term also is applied to a number of other small sprat-like forage fish (''Clupeoides'', ''Clupeonella ...

s. It is solitary when in the sea but becomes gregarious as it moves up-river in April, May and June to spawn.

Hybrid

In a paper published in July 2020, eggs from three Russian sturgeons were crossbred with

American paddlefish The American paddlefish (''Polyodon spathula''), also known as a Mississippi paddlefish, spoon-billed cat, or spoonbill, is a species of ray-finned fish. It is the last extant taxon, living species of paddlefish (Polyodontidae). This family is ...

using sperm from four male paddlefishes, resulting in successful hybrids called

sturddlefish The sturddlefish is a hybrid of the American paddlefish (''Polyodon spathula'') and the Russian sturgeon (''Acipenser gueldenstaedtii''), accidentally created by researchers in 2019 and announced in 2020. Obtaining living hybrids through breedi ...

. The resulting offspring had a survival rate of 62% to 74% and on average reached after a year of growth. This is the first time such fish from different genera and families successfully were crossbred.

Sources

* {{Taxonbar, from=Q747645 Acipenser Fish of the Black Sea Fish of the Caspian Sea Fish of the Sea of Azov Freshwater fish of Europe Freshwater fish of Asia Marine fish of Asia Marine fish of Europe Commercial fish Critically endangered fish Critically endangered fauna of Asia Critically endangered biota of Europe Taxa named by Johann Friedrich von Brandt Taxa named by Julius Theodor Christian Ratzeburg Taxonomy articles created by Polbot Fish described in 1833

Description

Distribution and habitat

Biology

Hybrid

See also

Sources