Salamon Mariusz A, Trif Nicolae, Krajewski Marcin, Wilk Alicja, Rubilar-Rodríguez Alfonso, Poatskievick-Pierezan Bruna, Płachno Bartosz J, Jain Sreepat
Faculty of Earth Sciences, Laboratory of Palaeontology and Stratigraphy, University of Silesia in Katowice, Będzińska 60, Sosnowiec, PL-41-200, Poland.
Brukenthal National Museum, Natural History Museum, Cetății St. 1-550160, Sibiu, Romania.
Sci Rep. 2025 Sep 10;15(1):32400. doi: 10.1038/s41598-025-13136-7.
Stalked crinoids are uncommon fossils in the Cenozoic. This is particularly due to their continuous decline starting from the Late Cretaceous and gradual restriction to the deep-sea environment, which bears a fossil record bias. On the other hand, in recent times, new data have emerged documenting some relict populations of sea lilies in the shallow marine facies from the Cenozoic. Here, we report shallow-water occurrences of Eocene crinoids from Romania that are classified as Isselicrinus. The representatives of Isselicrinus reached their greatest palaeogeographic distribution during the Eocene in offshore environments, and the only find of these crinoids from shallow-water facies was from the Southern Hemisphere. Thus, our discovery documents the first Eocene shallow-water occurrence of this taxon from the Northern Hemisphere. This finding shows that isocrinids locally might have remained in shallow environments after the initiation of the so-called Mesozoic marine revolution (MMR).
具柄海百合类是新生代罕见的化石。这尤其归因于它们从晚白垩世开始持续衰退，并逐渐局限于深海环境，而深海环境存在化石记录偏差。另一方面，近年来，出现了新的数据，记录了新生代浅海相中海百合的一些残留种群。在此，我们报告了罗马尼亚始新世具柄海百合类在浅水中的出现情况，它们被归类为伊塞利海百合属。伊塞利海百合属的代表在始新世期间在近海环境中达到了其最大古地理分布范围，而这些海百合类在浅海相中的唯一发现来自南半球。因此，我们的发现记录了该分类单元在北半球始新世首次出现在浅水中的情况。这一发现表明，在所谓的中生代海洋革命（MMR）开始后，等节海百合类可能在局部地区仍留在浅水环境中。
