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n.1.(Paleon.) A genus of fossil ganoid fishes found in the old red sandstone or Devonian formation. The head is large, and protected by a broad shield-shaped helmet prolonged behind into two lateral points.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
2008 for a description), and partial headshields of Cephalaspis sp.
The Early Devonian fish beds of the Midland Valley are considered lacustrine (Trewin and Davidson 1996; Braddy 2000, 2001), with Pterygotus anglicus at sites such as Tillywhandland sharing 'Lake Forfar' with acanthodians (Mesacanthus, Ischnacanthus and Euthacanthus) and ostracoderms (Cephalaspis pagei).