文摘
Cyrto- and orthocone nautiloids are described from the Upper Devonian (Frasnian) of the Prüm syncline. They belong to the familyCyrthoceratites d’Archiac & de Verneuil, 1842, with three species:C. depressus (Bronn, 1835),C. wallersheimensis n.sp. andC. cf.subconicus (G. & F.Sandberger, 1852) andStereotoceras Flower, 1950,Michelinoceras Foerste, 1932, as well asSphaerorthoceras Ristedt, 1968.