Analysis of information sources in references of the Wikipedia article "Clupeiformes" in English language version.
within Isospondyli (= Clupeiformes s. lato)
Under the name Isospondyli, Regan (1909) grouped the fishes having the verterbrae immediately after the skull similar in shape to the remaining ones, in contrast to the ostariophysans, in which the anterior vertebrae are greatly modified. Modern classifications have rejected this artificially constructed group, and the fishes previously assigned to it have been distributed among different orders (Clupeiformes, Osteoglossiformes, Salmoniformes, Cetomimiformes, etc.)