Late Ordovician Corals from Allochthonous Clasts in the Devonian Drik-Drik Formation of Northeastern New South Wales, Australia

Abstract

New coral material is documented from allochthonous limestones informally termed the ‘Trelawney Beds’, of the New England Region in northeastern New South Wales, enabling previous identifications to be revised. Taxa newly recognised in the Trelawney fauna include the tabulate corals Paleofavosites rarispinulatus Hall, 1975, and Navoites cargoensis (Hill, 1957), a lambelasmatid assigned to Coelostylinae gen. et sp. nov., the tryplasmatid Bowanophyllum? sp., and two indeterminate species of Heliolites and Propora. The taxonomic revisions strengthen similarities between the Trelawney fauna and that described from a comparable occurrence of allochthonous limestones informally known as the ‘Uralba Beds’ of the Manilla-Attunga area to the north, supporting a coral/stromatoporoid Fauna IIIb age (middle Katian) for both faunas. These Late Ordovician corals were likely eroded from the same carbonate shelf before redeposition into Silurian and Devonian sediments, now represented by the Glen Bell Formation and Drik-Drik Formation, respectively.