Fig. 10

Bivariate plots of conch parameters and septal spacing (of the last half volution) in the Late Givetian assemblage of Hassi Nebech (grey background dots represent the entire sample). A, D, G, J Conch width index (ww/dm) and septal spaces. B, E, H, K Whorl width index (ww/wh) and septal spaces. C, F, I, L Whorl expansion rate (WER) and septal spaces. A–C Complete assemblage. D–F Suborder Gephuroceratina. G–I Suborder Gephuroceratina. J–L Suborder Tornoceratina