Upper Ordovician strata exposed from the Baiyanhuashan section is the most representative Late Ordovician unit in the northwestern margin of the North China Craton (NCC). In total, 1,215 conodont specimens were obtained from 24 samples through the Wulanhudong and Baiyanhuashan formations at the Baiyanhuashan section. Thirty-six species belonging to 17 genera, including Tasmanognathus coronatus new species, are present. Based on this material, three conodont biozones—the Belodina confluens Biozone, the Yaoxianognathus neimengguensis Biozone, and the Yaoxianognathus yaoxianensis Biozone—have been documented, suggesting that the Baiyanhuashan conodont fauna has a stratigraphic range spanning the early to middle Katian. The Baiyanhuashan conodont fauna includes species both endemic to North China and widespread in tropical zones, allowing a reassessment of the previous correlations of the Katian conodont zonal successions proposed for North China with those established for shallow-water carbonate platforms at low latitudes.UUID: http://zoobank.org/7cedbd4a-4f7a-4be6-912f-a27fd041b586

中文翻译：

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华北克拉通西北缘卡田（晚奥陶世）牙形石

白岩花山剖面出露的上奥陶统地层是华北克拉通西北缘最具代表性的晚奥陶统单元。白燕花山断面乌兰湖洞组和白燕花山组共采集24个样品1215个牙形石标本。17属36种，包括冠鳐新物种，存在。基于这种材料，三个牙形石生物区——Belodina confluens生物区内蒙谷药仙颌生物区和姚仙雉生物带——有文献记载，表明白岩花山牙形石动物群的地层范围跨越卡田早期至中期。白岩花山牙形石动物群包括华北特有物种和热带地区广泛分布的物种，可以重新评估先前为华北提出的卡蒂牙形石带状演替与为低纬度浅水碳酸盐台地建立的相关性。UUID：http://zoobank.org/7cedbd4a-4f7a-4be6-912f-a27fd041b586