Neocardioceras juddii Zone

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Base: The base of the zone is immediately below the first appearance of the index species (Gale, 1995).

Top: The top of the zone is immediately above the last occurrence of the index species (Gale, 1995).

Range of index species: The zone is coincident with the total range of the index species (Gale, 1995).

Key fauna:

Bivalvia: Inoceramus ex gr. pictus
Pycnodonte vesiculare
Ammonoidea: Neocardioceras juddii
Sciponoceras sp. (locally abundant)

Faunal abundance & preservation: Sciponoceras is abundant at several levels in the zone, but is usually found as poorly preserved fragments of internal moulds.

Bio-markers: Gale (1996) recorded an acme of Pycnodonte vesiculare, overlain by three successive acmes of Sciponoceras.

Age: Upper Cenomanian