Graptolite zonation in the Late Wenlock (Early Silurian), with a new graptolite-brachiopod fauna from New South Wales
Abstract
The Panuara Formation at Cobblers Creek near Orange, New South Wales, Australia has yielded a graptolite-brachiopod fauna assigned to the sherrardae sub-Biozone (late Wenlock: Early Silurian). The sherrardae sub-Biozone as defined here is equivalent to the praedeubeli sub-Biozone, and is the lowest part of the ludensis Biozone. The ludensis Biozone is reappraised following restudy of the type specimens of Monograptus ludensis, which are shown to exhibit growth stages from the deubeli to the gerhardi condition. The graptolite fauna consists of Gothograptus chainos Lenz, G. marsupium Lenz, Pristiograptus jaegeri Holland, Rickards & Warren, Pristiograptus dubius (Suess), Monograptus ludensis (Murchison), Monograptus moorsi n.sp., Monograptus sp. and Lobograptus sherrardae (Sherwin). The limited shelly fauna includes the brachiopods Plectodonta brownae n.sp., Bracteoleptaena pannucea n.sp. and ?Lissatrypa.