Acipenser


Acipenser is a genus of sturgeons, containing three species native to freshwater and estuarine systems of eastern North America and Europe. It is the type genus of the family Acipenseridae and the order Acipenseriformes.

Taxonomy

Prior to 2025, Acipenser contained almost all species in the Acipenseridae outside of Huso and the "shovelnose" sturgeons. However, such a placement is now known to be paraphyletic with respect to the other genera, and these species have since been split into Huso and Sinosturio. Acipenser in the strict sense has been redefined with only 3 species.
This is an ancient genus, with phylogenetic evidence suggesting that it is the most basal sturgeon genus, having diverged from other sturgeons during the Early Cretaceous period. Several fossil species known as far back as the Late Cretaceous, with the fossils of two species known from mass mortality assemblages thought to immediately follow the Chicxulub impact, the beginning of the Cretaceous-Paleogene extinction event. However, the classification of these fossil species is uncertain under the new taxonomy; for example, "Acipenser" praeparatorum may actually represent a more derived sturgeon related to the Huso-''Pseudoscaphirhynchus'' lineage.

Extant species

The following three species are placed in this genus:

Fossil species

The following species are known from fossil remains, under a sensu lato interpretation of the genus. Almost all aside from A. amnisinferos and A. praeparatorum are thought to be nomina dubia.