Temporal range:
Acipenser oxyrhynchus.jpg
Atlantic sturgeon
(Acipenser oxyrinchus oxyrinchus)
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Acipenseriformes
Family: Acipenseridae
Bonaparte, 1831

Sturgeon is the common name for the 28 species of fish belonging to the family Acipenseridae. The earliest sturgeon fossils date to the Late Cretaceous, and are descended from other, earlier acipenseriform fish, which date back to the Early Jurassic period, some 174 to 201 million years ago. They are one of two living families of the Acipenseriformes alongside paddlefish (Polyodontidae). The family is grouped into four genera: Acipenser (which is paraphyletic, containing many distantly related sturgeon species), Huso, Scaphirhynchus, and Pseudoscaphirhynchus. Two species (A. naccarii and A. dabryanus) may be extinct in the wild, and one (P. fedtschenkoi) may be entirely extinct.[1] Sturgeons are native to subtropical, temperate and sub-Arctic rivers, lakes and coastlines of Eurasia and North America.[2]

Sturgeons are long-lived, late-maturing fishes with distinctive characteristics, such as a heterocercal caudal fin similar to those of sharks, and an elongated, spindle-like body that is smooth-skinned, scaleless, and armored with five lateral rows of bony plates called scutes. Several species can grow quite large, typically ranging 2–3.5 m (7–12 ft) in length. The largest sturgeon on record was a beluga female captured in the Volga Delta in 1827, measuring 7.2 m (23 ft 7 in) long and weighing 1,571 kg (3,463 lb). Most sturgeons are anadromous bottom-feeders, migrating upstream to spawn but spending most of their lives feeding in river deltas and estuaries. Some species inhabit freshwater environments exclusively, while others primarily inhabit marine environments near coastal areas, and are known to venture into open ocean.

Several species of sturgeon are harvested for their roe, which is processed into the luxury food caviar. This has led to serious overexploitation, which combined with other conservation threats, has brought most of the species to critically endangered status, at the edge of extinction.

  1. ^ Chadwick, Niki; Drzewinski, Pia; Hurt, Leigh Ann (March 18, 2010). "Sturgeon More Critically Endangered Than Any Other Group of Species". International News Release. International Union for Conservation of Nature. Retrieved September 19, 2015.
  2. ^ "Biology of Fishes (chapter: Biodiversity II: Primitive Bony Fishes and The Rise of Modern Teleosts)" (PDF). University of Washington. Retrieved May 30, 2014.

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