Abstract Conodont biostratigraphic and high-precision U-Pb isotope data are presented for the Permian-Triassic transition in three limestone hills, Gua Bama, Gua Panjang and Gua Sei, in the Malay Peninsula. Gua Bama yielded conodonts representating the Clarkina orientalis, Clarkina wangi and Clarkina subcarinata zones and the Wuchiapingian-Changhsingian stage boundary is identified for the first time in Malaysia. The Wuchiapingian subspecies Hindeodus julfensis wardlawi Kozur is elevated to species level, H. wardlawi, and evolved to the Changhsingian species Hindeodus julfensis Sweet and then Hindeodus changxingensis Wang. Distinguishing features and a new phylogeny of species of the genera Hindeodus and Isarcicella in the Late Permian-Early Triassic are presented. A new CA-TIMS high-precision U-Pb age of 253.70 ± 0.06 Ma for zircon from a tuff layer 6.5 m above the Wuchiapingian-Changhsingian boundary and in the lower part of the Clarkina subcarinata zone is reported. Conodont faunas from Gua Panjang represent the Clarkina changxingensis-Hindeodus praeparvus, Clarkina yini-Clarkina zhangi, and Hindeodus parvus zones and the PTB is placed at approximately 12 m in the studied 19 m thick sequence. Three tuff layers in the lower part of Gua Panjang contain zircon grains with CA-TIMS U-Pb ages of 252.23 ± 0.07 Ma, 252.47 ± 0.12 Ma and 252.16 ± 0.16 Ma (maximum age), respectively. Conodont faunas from Gua Sei represent the Upper Permian (Changhsingian) Clarkina hauschei - Hindeodus latidentatus Zone and the basal Triassic lower Induan (Griesbachian) Hindeodus parvus and Isarcicella staeschei zones. The PTB is placed at 30 m above the base of the Gua Sei sequence.

中文翻译：

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马来半岛上二叠统和下三叠统牙形石、高精度U-Pb锆石年龄和二叠纪-三叠纪边界

摘要 提供了马来半岛三个石灰岩山地瓜巴马、瓜班让和瓜塞的二叠纪-三叠纪转变的牙形石生物地层学和高精度 U-Pb 同位素数据。Gua Bama 产生了代表 Clarkina orientalis、Clarkina wangi 和 Clarkina subcarinata 带的牙形石，并且在马来西亚首次确定了五家坪阶-长兴阶边界。五家坪阶亚种Hindeodus julfensis wardlawi Kozur 被提升到种级H. wardlawi，并进化为长兴亚种Hindeodus julfensis Sweet 和Hindeodus changxingensis Wang。介绍了晚二叠世-早三叠世的 Hindeodus 和 Isarcicella 属的区别特征和新的系统发育。新的 CA-TIMS 高精度 U-Pb 年龄为 253.70 ± 0。06 Ma 来自五家坪阶-长兴阶边界以上 6.5 m 的凝灰岩层和克拉金纳亚隆起带下部的锆石。Gua Panjang 的牙形石动物群代表 Clarkina changxingensis-Hindeodus praeparvus、Clarkina yini-Clarkina zhangi 和 Hindeodus parvus 区，PTB 位于研究的 19 m 厚序列中的约 12 m 处。Gua Panjang 下部的三个凝灰岩层含有锆石颗粒，CA-TIMS U-Pb 年龄分别为 252.23 ± 0.07 Ma、252.47 ± 0.12 Ma 和 252.16 ± 0.16 Ma（最大年龄）。Gua Sei 的牙形石动物群代表上二叠纪（长兴纪）Clarkina hauschei - Hindeodus latidentatus 带和基底三叠纪下印度（Griesbachian）Hindeodus parvus 和Isarcicella staeschei 带。PTB 放置在 Gua Sei 层序底部上方 30 m 处。