The first record of Copodus Davis, 1883 (Chondrichthyes, Copodontiformes) from the Steshevian Regional Stage (Serpukhovian, Lower Carboniferous) of the Moscow Region

Abstract

Deposits of the Steshevian Regional Stage of the Lower Carboniferous Serpukhovian of the Moscow Region have yielded abundant and taxonomically diverse fish remains, which are usually disarticulated but frequently well preserved. The dental plates of chondrichthians assigned to the genus Copodus Davis, 1883 (Copodontiformes, Copodontidae), collected in the Zabor’e and Kalinovskie Vyselki localities (Moscow Region, Serpukhovskii District), have not previously been recorded in these beds. A new species, Copodus lebedevi sp. nov., is established based on the shape of plates, crown sculpturing, and unique shape of the wear facet. C. angulatus (Davis, 1883); C. cornutus Davis, 1883; C. planus (Davis, 1883); C. spatulatus Davis, 1883, C. aff. planus (Davis, 1883), C. cf. prototypus Davis, 1883, and C. aff. spatulatus Davis, 1883 are described for the first time from the Serpukhovian of Russia. The occlusal pattern of the upper and lower jaw plates in various species of the genus Copodus is reconstructed experimentally based on the shape of the wear facet. This shape depends on the structure of the upper and lower jaw plates and their particular parts and is distinctive in each species.