A new calcareous dinoflagellate cyst species, Orthopithonella collaris sp. nov., is described from the Cretaceous/Tertiary (K/T) boundary clay (Fish Clay) of Stevns Klint, Denmark, on the basis of SEM studies and light-microscopic analyses of thin sections of single specimens. The species has been found exclusively in the Fish Clay and as such may be a potential marker for the K/T boundary. Its pulse-like occurrence is thought to be due to the abrupt, relatively short-term ecological catastrophe associated with the K/T boundary event.

中文翻译：

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Orthopithonella colalis sp. 11 月，来自 K/T 边界的新钙质甲藻囊肿（Fish Clay，Stevns Klint/丹麦）

一种新的钙质甲藻囊肿物种 Orthopithonellacollis sp。11 月，根据扫描电镜研究和单个样品薄片的光学显微分析，描述了来自丹麦 Stevns Klint 的白垩纪/第三纪 (K/T) 边界粘土（鱼粘土）。该物种仅在鱼粘土中发现，因此可能是 K/T 边界的潜在标记。它的脉冲状发生被认为是由于与 K/T 边界事件相关的突然的、相对短期的生态灾难。