Sharpeiceras schlueteri Subzone

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Base: The base of the S. schlueteri Subzone is in the interval immediately below the common occurrence of the ammonite Sharpeiceras spp.

Top: The top of the subzone is below the common occurrence of the ammonite Mantelliceras saxbii (Wright & Kennedy, 1984), questionably identified in the Folkestone succession at the top of the M3 marker limestone (Gale & Friedrich, 1989).

Range of index species: The index species occurs in the nominate subzone and the M. saxbii Subzone (Wright & Kennedy, 1987).

Key Fauna:

Sharpeiceras spp.
Bivalvia: Inoceramus crippsi (locally very common)
Ammonoidea: Hypoturrilites gravesianus (locally very common)
Mantelliceras spp. (inflated forms)
Schloenbachia spp. (locally very common)

Faunal abundance & preservation: A much more diverse, and typically non-phosphatised fauna than occurs in the underlying N. carcitanense Subzone.

Bio-markers: Acmes of large Inoceramus crippsi crippsi, Hypoturrilites gravesianus and Schloenbachia varians in upper part of subzone.

Age: Early Cenomanian