Type
Subzone
Age range
7.67–6.57 Ma
Miocene
Messinian
Tortonian
N. kamtschatica - Nitz. rolandii
Rouxia californica
Thalassionema schraderi
7.77.77.67.57.57.57.47.37.37.37.27.27.17.07.07.06.96.86.86.86.76.76.66.5