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Abstract 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 ofArchaeoniscus brodieifrom 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 ofA. brodiei. The appendage morphology supports the interpretation ofA. brodieias 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. 

Two different morphotypes of fossil spheroidal and subcircular objects from the Pennsylvanian-Permian Remigiusberg Formation of the Saar-Nahe Basin are figured and described. These are interpreted as most likely representing branchiopod crustacean resting eggs and tetrapod egg strings, respectively. The putative presence of an arthropod egg bank indicates a stressed depositional palaeoenvironment near the excavated section and survival strategies of the producers comparable to those of extant branchiopod crustaceans. This highlights the exceptional preservation potential of the Remigiusberg Lagerstätte, hitherto mainly renowned for the occurrence of a diverse vertebrate fauna including many terrestrial taxa. 

Mantis shrimp (Stomatopoda) are extant, marine, predatory arthropods, but these malacostracan pancrustaceans are also occasionally preserved in fossil assemblages, particularly in Carboniferous and Cretaceous deposits. Carboniferous species fall into two suborders—Palaeostomatopodea and Archaeostomatopodea—and represent the ancestral forms that gave rise to modern lineages. Herein, we describe hitherto unknown specimens belonging to the archaeostomatopod genus Tyrannophontes from the Pennsylvanian-aged Wea Shale Member, eastern Nebraska. We explore the preservation of these fossils using scanning electron microscopy and energy dispersive X-ray spectroscopy. These approaches reveal additional morphological characteristics, including unique appendicular data, such as the earliest occurrence of biramous gilled appendages in Stomatopoda. We suggest that further examination of black shales will likely uncover novel records of these rare pancrustaceans.