Back
Chaenosphaerula sliwinskae
Chaenosphaerula sliwinskae, Sluijs and Brinkhuis, 2024, p. 454, pl. 2.
------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Sluijs and Brinkhuis, 2024, p. 454]:
Chaenosphaerula sliwinskae sp. nov.
Plate 2, S15, S16
Derivation of name. Named for Kasia K. Sliwinska in recognition of her achievements in marine palynology and organic geochemistry at the Geological Survey of Denmark and Greenland (GEUS), Copenhagen, Denmark.
Diagnosis. Gonyaulacoid cysts that are solely comprised of a periphragmal parasutural network; a central body (or endophragm) is not present. These match the criteria for attribution to Evittosphaerula (Manum, 1979) or Chaenosphaerula (Damassa, 1997). The network in this case is characterized by relatively broad, irregularly shaped bands, much like the Italian pasta, tagliatelle, typical for Chaenosphaerula. Occasionally, fragments of intratabular areas, attached to the parasutural “ribbons”, may be present as well. Reflected paratabulation appears gonyaulacean, matching that surmised for Chaenosphaerula. Archeopyle is uncertain due to the absence of all plates but most likely involves 3”.
Holotype. Plate 2, A–C
Paratypes. Plate 2, D–F, G–H
Material. IODP 302 Hole M0004A, Lomonosov Ridge, Arctic Ocean
Type locality and horizon. IODP 302 Hole M0004A, Lomonosov Ridge, Arctic Ocean, lower Eocene, Core 302-0004A-27X-2-0/1
Age. Early Eocene
Description.
Shape: subspherical.
Wall relationships: solely comprise a parasutural network; central body is not present.
Wall features: parasutural network comprising relatively broad bands, reminiscent of the pasta type, tagliatelle, delineating a standard gonyaulacoid tabulation. Parts of intratabular areas may be represented by smooth and thin wall material.
Processes: absent.
Paratabulation: indicated by parasutural network representing the periphragm, delineating a standard gonyaulacoid tabulation.
Archeopyle: unclear because only parasutural strands are represented, but, given the presence of all parasutures, the archeopyle may be a single-plate, presumably precingular, Type P (3” only).
Paracingulum: indicated by parasutural strands.
Parasulcus: indicated by parasutural strands.
Dimensions. Diameter 65(73)85 µm (n = 5).
Holotype. 80 µm.
Paratypes. 75 µm, 65 µm.
Stratigraphic range/occurrence. Early Eocene
Remarks. The species is distinct from Chaenosphaerula magnifica by its much broader and more irregularly shaped parasutural strands.
------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Sluijs and Brinkhuis, 2024, p. 454]:
Chaenosphaerula sliwinskae sp. nov.
Plate 2, S15, S16
Derivation of name. Named for Kasia K. Sliwinska in recognition of her achievements in marine palynology and organic geochemistry at the Geological Survey of Denmark and Greenland (GEUS), Copenhagen, Denmark.
Diagnosis. Gonyaulacoid cysts that are solely comprised of a periphragmal parasutural network; a central body (or endophragm) is not present. These match the criteria for attribution to Evittosphaerula (Manum, 1979) or Chaenosphaerula (Damassa, 1997). The network in this case is characterized by relatively broad, irregularly shaped bands, much like the Italian pasta, tagliatelle, typical for Chaenosphaerula. Occasionally, fragments of intratabular areas, attached to the parasutural “ribbons”, may be present as well. Reflected paratabulation appears gonyaulacean, matching that surmised for Chaenosphaerula. Archeopyle is uncertain due to the absence of all plates but most likely involves 3”.
Holotype. Plate 2, A–C
Paratypes. Plate 2, D–F, G–H
Material. IODP 302 Hole M0004A, Lomonosov Ridge, Arctic Ocean
Type locality and horizon. IODP 302 Hole M0004A, Lomonosov Ridge, Arctic Ocean, lower Eocene, Core 302-0004A-27X-2-0/1
Age. Early Eocene
Description.
Shape: subspherical.
Wall relationships: solely comprise a parasutural network; central body is not present.
Wall features: parasutural network comprising relatively broad bands, reminiscent of the pasta type, tagliatelle, delineating a standard gonyaulacoid tabulation. Parts of intratabular areas may be represented by smooth and thin wall material.
Processes: absent.
Paratabulation: indicated by parasutural network representing the periphragm, delineating a standard gonyaulacoid tabulation.
Archeopyle: unclear because only parasutural strands are represented, but, given the presence of all parasutures, the archeopyle may be a single-plate, presumably precingular, Type P (3” only).
Paracingulum: indicated by parasutural strands.
Parasulcus: indicated by parasutural strands.
Dimensions. Diameter 65(73)85 µm (n = 5).
Holotype. 80 µm.
Paratypes. 75 µm, 65 µm.
Stratigraphic range/occurrence. Early Eocene
Remarks. The species is distinct from Chaenosphaerula magnifica by its much broader and more irregularly shaped parasutural strands.