Late Late Cambrian trilobites from near Birch Inlet, south-western Tasmania

Abstract

The first late Late Cambrian basinal-facies trilobites to be described from Tasmania are from a succession exposed 8.5 km west of Birch Inlet, south-western Tasmania. Twenty-one taxa are described; the six agnostoid species include a new species of Leiagnostus, L. inletensis. The polymeroids include five new species: Hedinaspis uniformis, Proceratopyge longa, Niobella birchensis, Skljarella expansa and Ivshinaspis reticulata. Skljarella and Ivshinaspis are described for the first time from Australia. The specimens are preserved in siltstone belonging to a basinal facies; the facies faunas from northern Australia. The fauna is of late Late Cambrian age (Payntonian-earliest Datsonian) on the north Australian biostratigraphic scale. The Birch Inlet fauna is correlated with those of the Siyangshan Formation of Zhejiang, the Guoziguonen Formation of Xinjiang and the Shengjiawan Formation of Hunan. There are similarities with late Late Cambrian faunas from Nevada, Kazakhstan and New Zealand.