- Type images:
type material: B. tetradica
Catalog entries: Buryella tetradica
type material: B. tetradicaOriginal description: Shell of four segments subovate, smooth, with none of the strictures expressed externally. Cephalis subspherical, with a few circular pores, bearing a short, sharp horn or thorn. Collar stricture with four collar pores internally, and vertical pore expressed as a short horizontally directed tube. Thorax conical, with circular pores arranged in approximately three vague transverse rows or more irregular. Third segment largest, inflated, with greatest dimension medianly or in the distal half. Uniform circular pores are arranged in longitudinal and four to five transverse rows. Area between the longitudinal rows raised. Last segment inverted truncate-conical, with a smooth thinner wall and two to seven transverse rows of circular to elliptical pores. Distal margin scalloped or even, without a differentiated rim.
(Based on 20 specimens) Length overall, exclusive of horn, 120-185µm, length of cephalis and thorax 35-45µm, of third segment 40-65µm, of last segment 70-95µm; greatest width 70-95µm. Distinguishing characters (rw): The thorax of B. tetradica is considered homologous with the two postcephalic segments of B. pentadica. This difference in the number of segments between the cephalis and the large inflated segment serves to distinguish these two closely related species (B. pentadica, ancestor and B. tetradica, descendant). Phylogeny (rw): The thorax of B. tetradica is considered homologous with the two postcephalic segments of B. pentadica. This difference in the number of segments between the cephalis and the large inflated segment serves to distinguish these two closely related species (B. pentadica, ancestor and B. tetradica, descendant).
No descendants of B. tetradica have been recognized. Initially Foreman thought that B. tetradica was the ancestor of B. clinata, but subsequent studies [847] led her to believe that the ancestor is Pterocodon (?) anteclinata.
Remarks on original description: [Equivalent to Lithocampium sp. A, Riedel and Sanfilippo, 1971, pl.7, fig.12]
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:
Foreman, H. P. (1973b). Radiolaria of Leg 10 with systematics and ranges for the families Amphipyndacidae, Artostrobiidae, and Theoperidae. Initial Reports of the Deep Sea Drilling Project. 10: 407-474. gs O Hull, D. M. (1993). Quaternary, Eocene, and Cretaceous Radiolarians from the Hawaiian Arch, Northern Equatorial Pacific Ocean. Proceedings of the Ocean Drilling Program, Scientific Results. 136: 3-25. gs References:
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Buryella tetradica compiled by the radiolaria@mikrotax project team viewed: 5-6-2023
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