radiolaria - rads_cenozoic - Phormocyrtis striata praexquisita radiolaria - rads_cenozoic - Phormocyrtis striata praexquisita

Phormocyrtis striata praexquisita

Classification: rads_cenozoic -> Pterocorythidae -> Phormocyrtis -> Phormocyrtis striata -> Phormocyrtis striata praexquisita
Sister taxa: P. striata exquisita, P. striata praexquisita, P. striata striata


Citation: Phormocyrtis striata praexquisita Nishimura 1992
taxonomic rank: sub-species
Basionym: Phormocyrtis striata praexquisita
Taxonomic discussion: Nishimura 1992 Approved - Added on Leg 171 by Blome ; Paleogene RW_age: Lower part of Bekoma campechensis Zone.

Catalog entries: Phormocyrtis striata praexquisita

Original description: Cephalis subspherical, quite small, with very small pores all over, bearing a stout conical rod-like apical horn, three-bladed in the proximal part. Collar stricture with four collar pores internally, not defined externally. Cephalic structure has A, V, two L and D; V extends obliquely upward at quite a low angle, two l are incorporated into the stout septal ring. Two L and D are not connected to lateral ribs. Thorax subhemispherical, quite thick-walled, with subcircular pores with well-developed pore frames, slightly rough surface with nodal points. Abdomen inflated pyramidal, thick-walled, with subcircular, large pores, developing three convexly curved keels from the uppermost or median part of the abdomen, constricted aperture, termination ragged.
Remarks on original description: Equivalent to Phormocyrtis striata exquisita (Kozlova) Westberg et al., 1980, pl.1, fig.13.


Biogeography and Palaeobiology

Biostratigraphic distribution

Geological Range:
Last occurrence (top): within Paleogene Period (23.03-66.04Ma, top in Chattian stage). Data source: Lazarus et al. 2015 - "P age group"
First occurrence (base): within Paleogene Period (23.03-66.04Ma, base in Danian stage). Data source: Lazarus et al. 2015 - "P age group"

Plot of occurrence data:


Nishimura, A. (1992). Paleocene radiolarian biostratigraphy in the northeast Atlantic at Site 384, Leg 43, of the Deep Sea Drilling Project. Micropaleontology. 38(4): 317-362. gs


Phormocyrtis striata praexquisita compiled by the radiolaria@mikrotax project team viewed: 18-4-2024

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