Sturgeon belong to a special group of cartilaginous ganoids. They have not only scales, but also bones in the usual sense of the word: the inner skeleton of these fish consists of cartilaginous tissue. In addition, the sturgeon retains its chord for life - the primary supporting organ, which in other vertebrates is replaced by the spine during development.

Type: chordates.
Class: ray-finned fish.
Order: sturgeon.
Family: sturgeon.
Genus: sturgeon.
View: sterlet.
Latin name: Acipenser ruthenus.
Coloring: gray or smoky, sometimes with a light brownish-yellow openck (depends on the color of the soil and water), belly and bone plaques located in 5 rows, white.
Size: body length up to 125 cm, usually less than 1 m.
Weight: up to 12 kg, usually not more than 6.5 kg.
Life expectancy of a sterlet: up to 30 years.