Middle Cambrian (Series 3) arthropods (Trilobita, Agnostida) from CRA Exploration Scarr 1 drillhole, central Georgina Basin, Northern Territory

Samples obtained from the CRA Exploration Scarr 1 drillhole contain several species of agnostoid arthropods and trilobites. These include ?Criotypus sp., 'Acadagnostus' australis (Robison), Euagnostus sp., ?Onymagnostus sp., Opsidiscus sp., Lyriaspis sp. and an indeterminate polymerid, indicating a probable age of late Floran Euagnostus opimus Zone (Cambrian Series 3, Drumian) for the sampled interval of the Arthur Creek Formation. This indicates that the top of the lower unit of the Arthur Creek Formation in this area, as well as the top of the 'hot shale' (the thin basal unit of the lower Arthur Creek Formation) are both E. opimus Zone in age.