Nannotax Enabling nannofossil research

Description: Tubular murolith, with proximal and distal flanges, medium sized (Muller 1974 gives the size in the text as 3.5-4μm but according to the scale bar the holotype is 7μm across).

Remarks: Superficially similar to U. rotula in plan view, but easily distinguished by through-focusing. N.B. Assignment to Hayella is uncertain since structure of the, Eocene, type species H. situliformis, is unclear. H. challengeri appears structurally similar to Ochrosphaera neapolitana.

Range: NN?1 to ?12, common in NN4 to 6.

Synonym: Hayella aperta Theodoridis, 1984 - described as similar to H. challengeri but larger. However, the the holotype of H. aperta is only 8.5μm across vs 7μm for H. challengeri.