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The oldest known silicoflagellates occur in Albian sediments from ODP Site 693 (Weddell Sea near Antarctica) were originally studied in 1988.The silicoflagellate assemblage is dominated by Variramus, which possess extraordinary variability with no consistent skeletal morphology.More recently, portions of the Variramus assemblage are observed to be a minor component of a diverse Santonian flora in sediments from Devon Island of the Canadian Archipelago that includes a variety of species with triradiate (Cornua) or quadrate (Umpiocha, Schulzyocha) symmetries.