Nannotax Enabling nannofossil research

Decription: Small sphenolith with single apical spine and flaring proximal cycle.

Remarks: This is the most common of a group of rather delicate spinose sphenoliths. The other described species are S. capricornutus and S. calyculus. All three have only been reported from zones NP25 and NN1, and they may be a single, rather variable, species.

Size: Up to 8 microns long, but only 2-3 microns wide.

Range: NP25-NN1.

Synonym: Sphenolithus spp 1 & 2 Muller 1974a, pl. 4/3-8, 19/15-16.