Late Ediacaran organic microfossils from Finland

Abstract Here we present a detailed accounting of organic microfossils from late Ediacaran sediments Finland, the island Hailuoto (northwest Finnish coast), and Saarijärvi meteorite impact structure (~170 km northeast Hailuoto, mainland Finland). Fossils were recovered fine-grained thermally immature mudstones siltstones are preserved in exquisite detail. The majority forms sourced filamentous prokaryotic protistan-grade organisms forming interwoven microbial mats. Flattened Nostoc -ball-like masses bundled Siphonophycus filaments abundant, alongside Rugosoopsis Palaeolyngbya probable cyanobacterial origin. Acritarchs include Chuaria , Leiosphaeridia Symplassosphaeridium Synsphaeridium . Significantly, rare spine-shaped sclerites bilaterian origin recovered, providing new evidence for nascent fauna terminal Ediacaran. These findings offer direct body-fossil insight into mat-forming communities, demonstrate that trace fossils, detection prior to Cambrian might also be sought among emerging record small carbonaceous fossils (SCFs).