radiolaria - rads_cenozoic - Diartus petterssoni

Diartus petterssoni

Classification: rads_cenozoic -> Coccodiscidae -> Diartus -> Diartus petterssoni
Sister taxa: D. hughesi, D. petterssoni, D. sp.


Citation: Diartus petterssoni (Riedel and Sanfilippo 1970) Sanfilippo et al. 1985
Rank: species
Basionym: Cannartus? petterssoni

Taxonomic discussion:
(Riedel & Sanfilippo)1970 p.520 pl.14 fig.3 as Cannartus(?); Sanfilippo et al.1985 p.657 figs.8.10a-b

Catalog entries: Cannartus petterssoni

Original description: Cortical shell rather thick-walled, approximately cylindrical (sometimes bulged at the equator), with pronounced protuberances surrounding each end of the cortical shell. Pores of the cortical shell circular or subcircular, smaller near the equator. Two medullary shells, of which the outer is commonly spherical, sometimes lenticular. Very broad spongy columns (in some specimens divided into narrow parallel zones) are separated from the cortical shell by a narrow clearer zone: the distal margin of this clearer zone is commonly at the end of the protuberances.

Length of spongy columns 25-100 µ (commonly about 50 µ); their median breadth 50-85 µ. Length of cortical shell 80-100 µ; its maximum breadth (including protuberances) 75-95 µ. Breadth of outer medullary shell 25-40 µ. Distinguishing characters (rw): The most characteristic features are the broad, spongy columns at the ends of the subcylindrical to subspherical cortical shell, medullary shell tending to be spherical, and, in most specimens, pronounced tubercles in a single row at each end of the cortical shell. Closely related species are Didymocyrtis laticonus, which has tubercles more evenly distributed over the cortical shell, and Diartus hughesi, in which the skeletal structures at each end of the cortical shell are multiple concentric caps rather than spongy columns. Phylogeny (rw): This species originated from Didymocyrtis laticonus, and evolved into Diartus hughesi.


Biogeography and Palaeobiology

Biostratigraphic distribution

Geological Range:
Last occurrence (top): within Neogene Period (2.59-23.03Ma, top in Piacenzian stage). Data source: Lazarus et al. 2015 - "N age group"
First occurrence (base): within Neogene Period (2.59-23.03Ma, base in Aquitanian stage). Data source: Lazarus et al. 2015 - "N age group"

Plot of occurrence data:


Riedel, W. R. & Sanfilippo, A. (1970). Radiolaria, Leg. 4 DSDP. Initial Reports of the Deep Sea Drilling Project. 4: 503-575. gs

Sanfilippo, A., Westberg-Smith, M. J. & Riedel, W. R. (1985). Cenozoic Radiolaria. In, Bolli, H. M. , Saunders, J. B. & Perch-Nielsen K. (eds) Plankton Stratigraphy. Cambridge University Press, Cambridge 631-712. gs


Diartus petterssoni compiled by the radiolaria@mikrotax project team viewed: 28-9-2021

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