A morphological and taxonomic appraisal of the oldest anomalocaridid from the Lower Cambrian of Poland

Material previously referred to as Cassubia infercambriensis was re-examined and found to represent a composite fossil of a Peytoia-like anomalocaridid frontal appendage and an arthropod of uncertain affinities comparable to some bivalved arthropod taxa. The frontal appendage is referred to the genus Peytoia based on the presence of elongated ventral spines bearing a single row of auxiliary spines. As well as representing the oldest example of an anomalocaridid in the fossil record (Series 2, Stage 3), Peytoia infercambriensis is also the only record of this group from the East European Craton, therefore extending both the temporal and geographic range of the anomalocaridid family Hurdiidae.