A Late Ladinian to Early Carnian (Triassic) boreal radiolarian assemblage and two new species from the Omolon Massif (Northeastern Siberia, Russia)

Abstract A new radiolarian assemblage was recovered from upper Ladinian–lower Carnian strata of the southeastern part of Omolon Massif. The assemblage has several taxa in common with the upper Ladinian of the western part of the Omolon Massif and the lower Carnian of Kotel’nyi Island (New Siberian Islands, Arctic) and displays clear boreal features: low taxonomic and morphological diversity, abundance of taxa known from high-latitude regions and rare presence of taxa known from low-latitude areas. Two new species are described: Praenanina? hirsuta nov. sp. and Hindeosphaera venusta nov. sp.