A new actinopterygian Cheirolepis jonesi nov. sp. from the Givetian of Spitsbergen, Svalbard
Michael J. Newman, Carole J. Burrow, Jan L. den Blaauwen, Sam Giles
Abstract
Two specimens of a new early actinopterygian <i>Cheirolepis jonesi </i>nov. gen. et sp. have been collected from the lagoonal Middle Devonian (Givetian) Fiskekløfta Member, the upper member of the Tordalen Formation in the Mimerdalen Subgroup of Spitsbergen. This is the second oldest <i>Cheirolepis</i> species known from articulated remains. The holotype consists of an articulated head and the anterior trunk. The other specimen is an articulated skull which was 3-D scanned to determine the internal structure and general architecture. The new taxon differs from other <i>Cheirolepis</i> species in the relative dimensions of the bones of the head, including a narrow anterior end of the dentary, longer accessory operculum and correspondingly shorter dermohyal, as well as a longer premaxilla and proportionally larger quadratojugal, and the organisation and relative size of the teeth.<br/>