Article: Lower Devonian conodonts from New South Wales

Recent examination of the conodonts from the basal limestone of the Mandagery Park Formation suggests a middle to late Lochkovian (late Lower Gedinnian) age for this richly fossiliferous horizon. The fauna includes numerous early Lower Devonian conodonts but the characteristic early to late Praguian species Spathognathodus sulcatus and S. optimus are absent and this is significant in indicating a pre-Praguian upper age limit. A post-middle Lochkovian lower age limit is suggested by the presence of the conodonts Belodella devonica, B. triangularis, S. inclinatus wurmi, and S. remscheidensis in association with a brachiopod fauna which includes the genus Quadrithyris and several other Quadrithyris Zone brachiopods. Further, indirect, evidence of a late Lochkovian age is the association of Quadrithyris Zone brachiopods with Monograptus hercynicus in western North America. A table of correlation is given for some important Lower Devonian sequences in eastern Australia and western North America.