Bicknell Russell D C, Klompmaker Adiël A, Smith Patrick M, Hegna Thomas A
Division of Paleontology (Invertebrates), American Museum of Natural History, New York City, NY, 10027, USA.
Palaeoscience Research Centre, School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia.
Naturwissenschaften. 2025 Feb 10;112(2):16. doi: 10.1007/s00114-025-01962-8.
Marine isopod fossils represent a small component of the crustacean fossil record, contrasting the exceptional modern diversity of marine representatives of Isopoda. Examination of previously documented isopod species therefore presents an opportunity to derive additional paleobiological and taphonomic insight of these rare fossils. Here we consider two clusters of Archaeoniscus brodiei from the Lower Cretaceous (middle to upper Berriasian) Intermarine Member of the Durlston Formation, England. The individuals within the clusters are mostly complete, of similar size ranges, and are preserved on two different bedding planes. After examining these individuals, we illustrate, for the first time, appendages and eyes of A. brodiei. The appendage morphology supports the interpretation of A. brodiei as an isopod adapted to a benthic lifestyle. We propose that isopods from the Durlston Formation follow similar taphonomic pathways to arthropods preserved within plattenkalk-like deposits, resulting in enrichment in calcium carbonate and phosphate. Finally, the clusters reflect gregarious activities that were preserved during hypoxic events brought on by concurrent decay of algal blooms.
海洋等足类动物化石在甲壳类动物化石记录中只占一小部分，这与现代海洋等足类动物异常丰富的多样性形成了鲜明对比。因此，对先前记录的等足类物种进行研究，为深入了解这些稀有化石的古生物学和埋藏学特征提供了契机。在此，我们研究了来自英国德尔斯顿组下白垩统（贝里亚斯阶中部至上部）滨海层段的两簇布氏古等足虫化石。这些化石簇中的个体大多保存完整，大小相近，且保存在两个不同的层面上。在对这些个体进行研究之后，我们首次展示了布氏古等足虫的附肢和眼睛。附肢形态学研究支持了布氏古等足虫是一种适应底栖生活方式的等足类动物的观点。我们认为，德尔斯顿组的等足类动物化石与保存在类似板岩灰岩沉积物中的节肢动物有着相似的埋藏路径，从而导致碳酸钙和磷酸盐的富集。最后，这些化石簇反映了在藻类大量繁殖并发腐烂引发的缺氧事件中被保存下来的群居活动。
