Abstract—

Permian marine bivalves of the Pronchishchev Ridge (North Siberia) were systematically studied for the first time.. The presence of the Middle and Upper Permian with five biostratigraphic levels was established based on fossil findings. In the Middle Permian, these are the bivalve Kolymia inoceramiformis–K. plicata (undivided) and Kolymia multiformis zones, and in the Upper Permian—the Maitaia bella Zone (Beds with Phestia ex gr. ovata), Maitaia belliformis Zone, and Intomodesma costatum Zone. The bivalve assemblages from the Middle and the lower Upper Permian (up to the Intomodesma costatum Zone) are similar in their taxonomic composition to those from the Western and Northern Verkhoyansk regions. The uppermost Permian fossil assemblages (Intomodesma costatum Zone) are different. They are represented almost exclusively by monotaxonic aggregations of the large pectinoid Streblopteria rotunda (Lutkevich et Lobanova) and rather rare representatives of the genus Intomodesma. The marine basin of the present-day Pronchishchev Ridge had stable links with the Verkhoyansk basin throughout almost the entire Permian. This basin was very shallow and may have experienced episodes of desalination. In the end of the Permian, the paleogeographic situation changed, and the connection between the Pronchishchev Ridge and the East Taimyr basins became more pronounced. Most characteristic bivalve species are illustrated, and a new species Kolymia rutskovi Biakov, sp. nov. is described.

中文翻译：

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Pronchishchev 山脊（北西伯利亚）的二叠纪双壳类：分类组成、生物地层和生物地理关系的新数据

摘要-

Pronchishchev Ridge（北西伯利亚）的二叠纪海洋双壳类动物首次被系统地研究。根据化石发现确定了具有五个生物地层水平的中二叠纪和上二叠纪的存在。在中二叠世，这些是双壳类Kolymia inoceramiformis – K. plicata（未分裂）和Kolymia multiformis区域，以及在上二叠纪 – Maitaia bella区域（带有Phestia ex gr. ovata 的床）、Maitaia belliformis区域和Intomodesma costatum区。来自中二叠统和下二叠纪（直到Intomodesma costatum）的双壳类组合Zone) 的分类组成与来自西部和北部 Verkhoyansk 地区的分类组成相似。最上面的二叠纪化石组合（Intomodesma costatum Zone）是不同的。它们几乎完全由大型果胶Streblopteria rotunda (Lutkevich et Lobanova)的单分类聚集体和相当罕见的Intomodesma属代表. 现今普罗奇雪夫海岭的海盆几乎在整个二叠纪都与上扬斯克盆地保持着稳定的联系。这个盆地非常浅，可能经历过海水淡化。二叠纪末，古地理形势发生变化，普罗奇雪夫海岭与东泰米尔盆地的联系更加明显。图中显示了大多数典型的双壳类物种，以及一个新物种Kolymia rutskovi Biakov，sp。十一月 被描述。