Nannotax Enabling nannofossil research

Description: 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: Described as 8 to 12 microns long (Bukry 1973), but smaller speciemns with similar morphology are usually more common.

Original description:

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