An upper Turonian (Upper Cretaceous) inoceramid zonation and a round-the-world trip with Mytiloides incertus (Jimbo, 1894)

We reviewed the global stratigraphic and palaeobiogeographic distribution of Mytiloides incertus (Jimbo, 1894) in the context of a newly proposed standard inoceramid zonation for the central European upper Turonian (perplexus, striatoconcentricus, labiatoidiformis, scupini, waltersdorfensis waltersdorfensis interval zones). Where available, δ13C curves aided an interbasinal correlation. M. incertus enters first in the striatoconcentricus IZ. Last well-dated occurrences are from the lower scupini IZ. An acme of the species in the terminal labiatoidiformis IZ appears to be isochronous in Europe and the Western Interior of the United States. The occurrence of M. incertus together with other central European species (I. perplexus, M. striatoconcentricus) marks the end of an inoceramid endemic phase in the Western Interior.