Bathylagus
Bathylagus is a genus of deep-sea smelts, some species of which are noted for having stylophthalmine larvae.
Species
The seven recognized, extant species in this genus are:Bathylagus andriashevi Kobyliansky, 1986Bathylagus antarcticus Günther, 1878 Bathylagus euryops Goode & T. H. Bean, 1896 Bathylagus gracilis Lönnberg, 1905Bathylagus niger Kobyliansky, 2006Bathylagus pacificus C. H. Gilbert, 1890 Bathylagus tenuis Kobyliansky, 1986The oldest fossil species in this genus known from skeletal remains are from the Miocene. These include Bathylagus angelensis, whose remains are widespread across Southern California, as well as B. sencta, B. obesa, and B. toyohamaensis from Japan. These specimens are all known from formations that were formerly deposited in deep-sea environments, before being dramatically uplifted to the surface by geological activity. However, tentative fossil otoliths are also known from the Late Cretaceous of the United States.