Gonioteuthis granulata Zone

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Base: In both the European standard and English successions, the base of the zone is recognised by the first occurrence of the index species (Christensen, 1991).

Range of index species: In both the European standard and English successions, the range of the index species is co-extensive with the nominate zone, but in the English succession there is an acme of the index species at the top of the zone (Christensen, 1991). There is also an acme of the relatively long-ranging Actinocamax versus in the middle of the zone (Christensen, 1991).

Biostratigraphical correlation: The zone equates with most of the U. socialis Zone and the overlying M. testudinarius and U. anglicus zones of the standard macrofossil zonal scheme for the UK Chalk Group (Christensen, 1991).

Lithostratigraphical correlation: The zone can be inferred to equate with the lower part of the Newhaven Chalk Formation of southern England.

Age: Santonian and basal Campanian (sensu anglico)