The first named Ediacaran body fossil, <i>Aspidella Terranovica</i>

<jats:p> <jats:italic>Aspidella terranovica</jats:italic> Billings, 1872 was first described from the late Neoproterozoic Fermeuse Formation (St. John's Group) on the Avalon Peninsula of eastern Newfoundland, approximately 1km stratigraphically above the famous Ediacaran biota at Mistaken Point, and several kilometres below the base of the Cambrian. <jats:italic>Aspidella</jats:italic> has been reinterpreted perhaps more than any other Precambrian taxon, and has variously been regarded as a fossil mollusc or ‘medusoid’, a gas escape structure, a concretion, or a mechanical suction mark. Our studies indicate that <jats:italic>Aspidella</jats:italic> includes a wide variety of preservational morphs varying from negative hyporeliefs with a raised rim and ridges radiating from a slit (<jats:italic>Aspidella</jats:italic>‐type preservation), to flat discs with a central boss and sharp outer ring (<jats:italic>Spriggia</jats:italic> preservation), to positive hyporeliefs with concentric ornamentation (<jats:italic>Ediacaria</jats:italic> preservation). Specimens occur in a continuum of sizes, with preservational styles dependent on the size of the specimen and the grain size of the host lithology; the elongation of specimens is tectonic. <jats:italic>Aspidella</jats:italic> is confirmed as a body fossil from observations of complex radial and concentric ornamentation, mutually deformed borders in clusters of specimens, and occurrence on the same bedding planes as certain distinctive Ediacaran taxa. <jats:italic>Aspidella</jats:italic> is indistinguishable from, and has priority over, several of the most common genera of late Neoproterozoic discoidal body fossils worldwide. Similar fossils from Australia are interpreted as holdfasts of frond‐like organisms. The density of specimens in the <jats:italic>Aspidella</jats:italic> beds suggests levels of benthic biomass in the Neoproterozoic that could rival those of modern marine communities. The serial growth forms, <jats:italic>Palaeopascichnus</jats:italic><jats:italic>Intrites, Neonereites renarius</jats:italic><jats:italic>Yelovichnus</jats:italic>, associated with <jats:italic>Aspidella</jats:italic>, are interpreted as body fossils of unknown affinities rather than trace fossils. A new, trilobed, Ediacaran body fossil, <jats:italic>Triforillonia costellae</jats:italic> gen. et sp. nov., is described from the <jats:italic>Aspidella</jats:italic> beds of the Fermeuse Formation.</jats:p>