Geological Range: Last occurrence (top): within Early Valanginian Substage (136.41-139.39Ma, top in Valanginian stage). Data source: Perch-Nielsen 1988 First occurrence (base): within Late Berriasian Substage (139.39-141.93Ma, base in Berriasian stage). Data source: Perch-Nielsen 1988
Plot of occurrence data:
Range-bar - range as quoted above, pink interval top occurs in, green interval base occurs in.
Triangles indicate an event for which a precise placement has been suggested
(NB There is no histogram as there are no occurrence records for the taxon in the Neptune database) Parent: N. abundans group
Jeremiah, J. (2001). A Lower Cretaceous nannofossil zonation for the North Sea Basin. Journal of Micropalaeontology. 20(1): 45-80. gsVO
Perch-Nielsen, K. (1988). New Lower Cretaceous calcareous nannofossil species from England. INA Newsletter. 10(1): 30-37. gsVO
Nannoconus concavus compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 15-8-2022