Article: A new naked jawless vertebrate from the Middle Devonian of Scotland

A new jawless vertebrate, Achanarella trewini gen. et sp. nov., is described from some recently discovered, relatively well-preserved specimens from the Achanarras fish bed at Achanarras Quarry, northern Scotland. The Achanarras fish bed is of Middle Devonian (Eifelian) age. Achanarella is a torpedo-shaped jawless vertebrate with a strongly hypocercal tail and well-developed anal fin. It has at least 13 branchial openings with possibly more than 20. It is scaleless. Achanarella compares well with the Frasnian Euphaneropidae of the Escuminac Formation in Quebec, Canada, and Cornovichthys blaauweni Newman and Trewin, 2001, also from the Achanarras fish bed. It differs from these forms mainly in being extremely long and thin and having a very small head compared with body length.