Sample size of specimens from each taxon studied from different lithofacies of the Purisima Formation.

Abbreviations: Shc, hummocky cross-stratified sandstone lithofacies; Mld, laminated diatomite lithofacies; Mm, massive mudrock lithofacies; Mpm, massive pebbly mudrock lithofacies; Spm, massive pebbly sandstone lithofacies; Ms, massive sandstone lithofacies.