A new Permian species of Mooreoceras (Cephalopoda: Orthocerida) from northwestern Peninsular Malaysia

Abstract

A new orthocerid cephalopod species, Mooreoceras sibumasuense sp. nov., is described from the lowest part of the Chuping Formation in Bukit Tungku Lembu of the Perlis State, northwestern Peninsular Malaysia. The holotype of the species occurs in argillaceous limestone that is most likely late Kungurian (late Early Permian) in age and was deposited under cool-temperate water conditions on the Sibumasu Terrane of the eastern Cimmerian Continent. Most Permian species of Mooreoceras appear to be palaeobiogeographically confined to cool to cool-temperate palaeoclimate zones of the Australian Gondwana to Sibumasu region. Mooreoceras sibumasuense sp. nov. belongs to a group that probably survived due to isolation from high predatory stress in tropical to temperate seas.