The significance of Upper Permian brachiopods from Merapoh area, northwest Pahang

Several localities of Upper Permian brachiopod dominated shelly fauna have been discovered from the Merapoh area in northwest Pahang. The fauna consists of more than forty species of free living and pedunculate brachiopods, associated with other benthic elements such as bivalves, gastropods, fenestrate and stony bryozoans, solitary rugose corals, trilobites etc. Most of the fossils are preserved as moulds and casts, but they show very good biocoenosis assemblages. The brachiopods assemblages belong to the Upper Permian Leptodus Shale fauna which shows some similarities with other Upper Permian fauna from southern Tethyan region. Stratigraphically, the brachiopod fauna can be divided into two zones, the Oldhamina dicipens and the Haydenella minuta Zones, equivalent to the lower and middle Dorashamian (= Changshingian) Stages, respectively. The Leptodus Shale fauna is developed on shallow carbonate and volcanic high during a period of active volcanism