Published online by Cambridge University Press: 20 May 2016
The extensive fauna of vertebrates from the Lower Devonian Water Canyon Formation of Utah was initially reported and described by Branson and Mehl (1930, 1931), and subsequently described in detail by Denison (1952, 1953, 1958, 1967). A major part of the fauna consists of heterostracans, particularly pteraspidids (Denison, 1953, 1967), and to date six species are known from the Water Canyon Formation. This fauna comes from the upper Emsian and is similar in age to that of the Beartooth Butte Formation of Wyoming and Montana, and also to faunas recently reported from Nevada and California (Elliott, 1989; Ilyes and Elliott, 1991, 1992).