Blackites gladius

Rhabdosphaera gladius Locker, 1967

Species of Blackites Hay & Towe (1962) having a broad hollow distal process inflated near the distal end before tapering to a point. A distinct collar attached to the base of the hollow distal process. The cross-hatched pattern at the inflated part of the distal process is diagnostic for this species. The width of the distal process at its widest point is less than the diameter of the complete base.

Blackites gladius differs from Blackites creber (Deflandre in Deflandre & Fert, 1954) Sherwood (1974) by having a broader, more inflated distal process, but some intermediate forms are present. It is distinguished from Blackites rotundus Bown (2005) by having a less globular distal process

Bown, P. R., (2005): Palaeogene calcareous nannofossils from the Kilwa and Lindi areas of coastal Tanzania (Tanzania Drilling Project 2003-4). - Journal of Nannoplankton Research. 27(1): 21-95.

Deflandre, G. & Fert, C., (1954): Observations sur les coccolithophoridés actuels et fossiles en microscopie ordinaire et électronique. - Annales de Paléontologie. 40: 115-176.

Hay, W. W. & Towe, K. M., (1962): Electron microscope examination of some coccoliths from Donzacq (France). - Eclogae Geologicae Helvetiae. 55: 497-517.

Locker, S., (1967): Neue, statigraphisch wichtige Coccolithophoriden (Flagellata aus dem norddeutschen Altetiar). - Monatsberichte der Deutschen Akademie der Wissenschaften zu Berlin. 9(9-10): 758-769

Sherwood, R. W., (1974): Calcareous nannofossil systematics, palaeoecology and biostratigraphy of the Middle Eocene Weches Formation of Texas. - Tulane Studies in Geology. 11: 1-79