Gasterosteus
Gasterosteus is a genus of ray-finned fishes belonging to the family Gasterosteidae, the sticklebacks. These fishes are found in freshwater, brackish water and marine habitats in the Holarctic region.
Species
There are currently 6 recognized species in this genus:Gasterosteus aculeatus Linnaeus, 1758 Gasterosteus crenobiontus Băcescu & R. Mayer, 1956 Gasterosteus islandicus Sauvage, 1874 Gasterosteus microcephalus Girard, 1854 Gasterosteus nipponicus Higuchi, Sakai & A. Goto, 2014 Gasterosteus wheatlandi Putnam, 1867Additionally there are a number of fossil species including:Gasterosteus abnormis Gretchina, 1981 Gasterosteus doryssus Gasterosteus kamoensis Nazarkin, Yabumoto & Urabe, 2013 Gasterosteus orientalis Sychevskaya, 1981
Fossils of essentially modern three-spined sticklebacks, assigned to G. aculeatus, are known from the mid-late Miocene of California, USA.