Article: Two new early Cretaceous dinocyst species from the northern North Sea

Two new species of dinocyst, Oligosphaeridium abaculum and Systematophora silyba, are described from a Barremian assemblage obtained from the northern North Sea north-east of the Shetlands. O. abaculum is the first-known hystrichosphere with plate-centred tubular processes on which a clearly defined paratabulation is present and this is described in detail. The paratabulation is of the Gonyaulax-type, and it is inferred that chorate cysts with similar morphology are also of this type.