Neostlingoceras carcitanense Subzone

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Base: The base of the subzone is the base of the M. mantelli Zone.

Top: The top of the zone occurs in the interval immediately below the occurrence of common specimens of the ammonite Sharpeiceras spp. (Gale & Friedrich, 1989; Gale, 1995). Range of index species: Occurs in nominate subzone, and rare or absent in S. schlueteri Subzone (Gale & Friedrich, 1989).

Key Fauna:

Porifera: Stauronema carteri
Brachiopoda: Tropeothyris? carteri
Bivalvia: Aucellina spp. (locally common)
Inoceramus anglicus
Ammonoidea: Anisoceras spp.
Idiohamites spp.
Mantelliceras mantelli
Neostlingoceras carcitanense
Sciponoceras spp.

The occurrence of heteromorph ammonites (eg. Anisoceras spp., Idiohamites spp., Neostlingoceras spp. & Sciponoceras spp.) and the bivalve Aucellina is particulary characteristic of the N. carcitanense Subzone.

Faunal abundance & preservation: Typically a low diversity, phosphatised fauna.

Bio-Markers: The bivalve Aucellina is common.

Age: Earliest Cenomanian