Biomarker 9: Stensioeina granulata polonica FDO

Found in the Mackerel Formation of the Central North Sea and in the lower Jukes Formation in the Southern North Sea ('Mid' Santonian, basal socialis Zone). Other species include common Gavelinella stelligera, and an influx of planktonic species including Whitinella baltica and Hedbergella delrioensis.

Correlation: This biomarker can be placed in the BGS foraminiferal Biozone 18i or possibly top 17 (Wilkinson, 2000).