Shelly coprolites record durophagous predation in the Late Ordovician Bohdalec Formation (Katian; Prague Basin, Czech Republic)

Trace fossils can illustrate important palaeobiological interactions within a fossil assemblage that body fossils do not record. A group of trace fossils that showcase feeding ecology, and evidence of predation, are coprolites. Shelly coprolites are useful for documenting records of durophagous predators or scavengers within a substrate. To expand the record of these traces from the lower Paleozoic, here we present 12 shelly coprolites from the Late Ordovician (Katian) Bohdalec Formation of the Czech Republic. These coprolites contain abundant Onnia superba (Bancroft, 1929) fragments with marked breakages across exoskeletal sections. Rarer evidence for gastropods, bivalves, crinoid debris, and another indeterminate shelly material are also observed within the coprolites. While the producer cannot be irrevocably determined, possible options are explored. We propose that larger, co-occurring trilobites and predatory cephalopods likely made the majority of coprolites. Furthermore, large unbiomineralised arthropods, such as phyllocarids and eurypterids are highlighted as possible producers. Continued examination of these trace fossils will highlight when and where similar interactions between trophic levels had occurred.