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Cannosphaeropsis hughesii
From Fensome et al., 2019:
Cannosphaeropsis hughesii Harding, 1990b, p.24–25, pl.6, figs.9–16 ex Harding in Williams et al., 1998, p.92. Holotype: Harding,
1990b, pl.6, figs.10,14. This name was not validly published in Harding (1990b) since the lodgement of the
holotype was not specified (ICN Article 40.7). Age: late Hauterivian.
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Original description: [Harding, 1990, p. 24]:
Diagnosis:
Shape: Ambitus subcicular to prolate ovoidal. Outline modified by parasutural processes and ectophragmal trabeculae. Greatest width across posterior cingular parasuture. Hypocyst slightly longer than epicyst. Apparently no dorso-ventral compression.
Phragma: Ectophragm reduced to rod-like trabeculae (ca. 0.7 µm dia) which appear to be looped from one parasutural process to the next. Trabeculae posses small distal outgrowths or nodes. Autophragm ca. 1.5 µm thick, cyst surface has "orange-peel" texture with rare hemispherical intratabular tubercles (ca. 1.5 µm dia). Parasutural processes are solid, cylindrical (1µm dia) and usually discrete but may anastomose and bifurcate. Height of processes up to 5 µm.
Paratabulation: L-type sexiform gonyaulacoid. Paratabulation as indicated by parasutural processes and trabeculae: 4", 6", 6c, 6""", 1"""", 1p, 5s. Size and relationships of paraplates difficult to determine in many cases due to compression and displacement of trabeculae. ai large with ai/lu just posterior to A/li. Iu elongate and narrow along parasulcus.
Archaeopyle: Type P4, free, monoplacoid operculum, slightly reduced.
Paracingulum: Marked by parallel trabeculae, laevorotatory, displaced by two cingulum widths.
ParasuIcus: L-type, clearly consisting of 5 sulcals and lu.
Dimensions:
Length (49) 45 (43) µm. Width (42) 38.8 (36) µm. Specimens = 5 (5).
Affinities: (p.25):
A rare species encountered in the oldest samples studied, it lacks parasutural septa and thus does not conform to Williams and Downie's (1966) diagnosis of the genus Nematosphaeropsis. Differs from other species of Cannosphaeropsis by its small size and the diminutive extra-trabecular nodes.
Cannosphaeropsis hughesii Harding, 1990b, p.24–25, pl.6, figs.9–16 ex Harding in Williams et al., 1998, p.92. Holotype: Harding,
1990b, pl.6, figs.10,14. This name was not validly published in Harding (1990b) since the lodgement of the
holotype was not specified (ICN Article 40.7). Age: late Hauterivian.
---------------------------------------------------------------------------------------------------
Original description: [Harding, 1990, p. 24]:
Diagnosis:
Shape: Ambitus subcicular to prolate ovoidal. Outline modified by parasutural processes and ectophragmal trabeculae. Greatest width across posterior cingular parasuture. Hypocyst slightly longer than epicyst. Apparently no dorso-ventral compression.
Phragma: Ectophragm reduced to rod-like trabeculae (ca. 0.7 µm dia) which appear to be looped from one parasutural process to the next. Trabeculae posses small distal outgrowths or nodes. Autophragm ca. 1.5 µm thick, cyst surface has "orange-peel" texture with rare hemispherical intratabular tubercles (ca. 1.5 µm dia). Parasutural processes are solid, cylindrical (1µm dia) and usually discrete but may anastomose and bifurcate. Height of processes up to 5 µm.
Paratabulation: L-type sexiform gonyaulacoid. Paratabulation as indicated by parasutural processes and trabeculae: 4", 6", 6c, 6""", 1"""", 1p, 5s. Size and relationships of paraplates difficult to determine in many cases due to compression and displacement of trabeculae. ai large with ai/lu just posterior to A/li. Iu elongate and narrow along parasulcus.
Archaeopyle: Type P4, free, monoplacoid operculum, slightly reduced.
Paracingulum: Marked by parallel trabeculae, laevorotatory, displaced by two cingulum widths.
ParasuIcus: L-type, clearly consisting of 5 sulcals and lu.
Dimensions:
Length (49) 45 (43) µm. Width (42) 38.8 (36) µm. Specimens = 5 (5).
Affinities: (p.25):
A rare species encountered in the oldest samples studied, it lacks parasutural septa and thus does not conform to Williams and Downie's (1966) diagnosis of the genus Nematosphaeropsis. Differs from other species of Cannosphaeropsis by its small size and the diminutive extra-trabecular nodes.