Late Devonian radiolarians from the Rudny Altai (SW Siberia)

Abstract

Four well-preserved radiolarian associations recovered from the uppermost Givetian-upper Frasnian siliceous strata of the Zolotukha and Gryaznukha formations near Gornyak Settlement in the Altai-Sayan Folded Area (ASFA) in the South West Rudny Altai, southwestern Siberia, eastern Russia, are represented by 26 species assigned to 11 genera including a new taxon, Cancellientactinia acifera gen. et sp. nov. The validity of the genera Entactinia Foreman and Stigmosphaerostylus Rüst is discussed and the diagnosis of the genus Trilonche Hinde is emended. The main Frasnian fauna is dominated by spherical entactiniids whereas spiny ceratoikiscids and palaeoscenids possess more diversity in the later transitional Frasnian-Famennian association.