Pseudoscaphirhynchus

Pseudoscaphirhynchus
Pseudoscaphirhynchus fedtschenkoi
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Acipenseriformes
Family: Acipenseridae
Genus: Pseudoscaphirhynchus
A. M. Nikolskii, 1900
Species
Blue: Pseudoscaphirhynchus fedtschenkoi

Red: Pseudoscaphirhynchus hermanni Yellow: Pseudoscaphirhynchus kaufmanni(overlapping range)

Synonyms
  • Kessleria Boghdanov 1882 non Nowicki 1864 non Lichtenstein 1886
  • Pseudoscaphirhynchus (Hemiscaphirhynchus) Berg 1911
  • Hemiscaphirhynchus (Berg 1911)

Pseudoscaphirhynchus is a genus of relatively small, highly threatened sturgeons that are restricted to the Aral Sea system (although extirpated from the Aral Sea itself), including the Amu Darya and Syr Darya river basins, in Central Asia.

P. fedtschenkoi is restricted to Syr Darya, but has not been seen in decades and it is possibly extinct. The two other species in the genus are restricted to Amu Darya: P. hermanni survives in very low numbers and P. kaufmanni in low numbers, with both being rated as Critically Endangered by the IUCN.

Compared to other sturgeons, Pseudoscaphirhynchus are small. The largest species, P. kaufmanni, reaches up to 75 cm (30 in) in total length (excluding tail filament), while the smallest, P. hermanni, only reaches 27.5 cm (10.8 in), making it the smallest member of the sturgeon family. P. kaufmanni has a long thin tail filament, P. hermanni lacks it, and it can be long or short in P. fedtschenkoi. They have a relatively long, broad and flattened snout, somewhat like Scaphirhynchus of North America. Little is known about the behavior of Pseudoscaphirhynchus, but they mainly feed on the bottom on small fish and aquatic insect larvae.