Archaeocyaths of the White Point Conglomerate, Kangaroo Island, South Australia

Abstract

The White Point Conglomerate at Cape d’Estaing, Kangaroo Island, South Australia contains a polymict suite of transported clasts up to boulder size, including archaeocyath-bearing limestone clasts. Reef boundstone and bioclast floatstone and rudstone textures are evident among the limestones. The formation is a constituent of the Kangaroo Island Group, exposed along the central northern coast of the island. A total of 32 species of archaeocyaths, one radiocyath and one acanthinocyathide are described from sampled clasts. New taxa are the ethmocyathid Ussuricyathellus bellidoi sp. nov. and the sajanocyathid Emucyathus elinorae gen. et sp. nov. The assemblage correlates with the post–Flinders Unconformity interval elswhere in the Stansbury Basin and in the Arrowie Basin to the north, and indicates a late Botoman age in terms of the Siberian Cambrian stage scale. A substantial proportion of species in common between the Cape d’Estaing assemblage and the Koolywurtie Limestone Member fauna on Yorke Peninsula confirm that the latter unit is the likely source for the archaeocyath-bearing limestone clasts in the White Point Conglomerate. In contrast, there are no species in common between the Cape d’Estaing assemblage and that of the upper Sellick Hill Formation and lower Fork Tree Limestone on Fleurieu Peninsula.http://zoobank.org/urn:lsid:zoobank.org:pub:FC416BB7-F7CF-403E-8343-D98214726CE9