Chinese Permian fusulinid generic zones and international Permian stages

The Permian Stages have long been defined by fusulinid generic zones (Genozones), for instance, the Palaeofusu;ina Zone for the Changhsingian Stage and the Gallowayinella Zone for the Wuchiapingian Stage. Such fusulinid zones, from a historical point of view, had played important roles in China’s relevant stratigraphical research. However, fusulinid genera that are selected as zonal indices of the Permian Stages usually have long-ranging forms of regional distribution and consequently the zones can not be clearly and accurately defined. In fact, such kind of generic zones have caused some confusion in stratigraphic correlation. For example, Palaeofusul; ina actually ranges from the early Wuchapingian Stage to the late Changhsingian Stage, rather than are the Changhsingian Stage as some experts advocated, and some can also be applied to some other genera, e.g. Codonofusiella and Reichelina. Therefore, all the Permian fusulinid generic zones have to be re-examined. Obviously, fusulinids are not suitable for the definition of Permian Stages. Now conodonts are used as the leading fossil group in defining the 9 stages and 3 series of the Permian, as adopted by the International Commission on Stratigraphy. Two main tasks of Permian biostratigraphy research in the future are (1) establishment of phylogenetic relationship at the species level within every fusulinid genus, and (2) exact correlation of the fusulinid sequence mainly in the shallow water facies with conodont zones mainly in the deep water facies. Fusulinid generic zones established in China should be not used again.