Applinocrinus cretaceus Subzone

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This interval of the G. quadrata Zone has only been formally recognised in southern England.

Base: In southern England, the base of the subzone is placed at the Lancing Flint (Mortimore, 1986).

Top: In southern England, the top of the subzone is placed at the Whitecliff Flint (Bailey et al., 1983).

Range of index species: The index ranges from the Lancing Flint to the Whitecliff Flint (Bailey et al., 1983).

Key fauna:

Annelida: Conorca turbinella (locally abundant)
Bryozoa: locally abundant bryozoans
Brachiopoda: Cretirhynchia intermedia
C. limbata
Kingena blackmoorei
Bivalvia: Inoceramus sarumensis
I. subsarumensis
Belemnoidea: Gonioteuthis quadrata
Crinoidea: Applinocrinus cretaceus
Echinoidea: Cidaris subvesiculosa sensu Gaster (1924)
Echinocorys marginata
Offaster pilula nana

Faunal abundance & preservation: The subzone is dominated by small fossils, the larger fauna being mostly crushed and fragmentary. The index fossil is very small and inconspicuous. The best guide to the subzone are the locally abundant bryozoans, usually preserved as greyish or pinkish fronds.

Bio-markers: The key fauna is fairly evenly distributed throughout the subzone, although often localised into horizons of abundance, separated by poorly fossiliferous chalk.

Age: Campanian.