Shelly fossils from the early Cambrian (Toyonian) Wirrealpa, Aroona Creek, and Ramsay Limestones of south Australia

Small shelly fossils from the Wirrealpa and Aroona Creek Limestones, Flinders Ranges, and the temporally equivalent Ramsay Limestone, Yorke Peninsula, South Australia, are described and assessed. These formations have traditionally been assigned an early Middle Cambrian age. However, new data suggest that a late Early Cambrian age (equivalent to the Toyonian Stage from the Siberian Platform) is more appropriate for these units. Twenty-four taxa, including a number of problematica, poriferans, coeloscleritophorans, palaeoscolecidans, "conodontomorphs,' hyolithelminthes, hyoliths, mollusks, and inarticulate brachiopods, are reported. -from Authors