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Chytroeisphaeridia conspicua
Plate 3, Figures 1-4
Chytroeisphaeridia scabrata Pocock 1972. – LEEREVELD 1997b, fig. 10a.
Holotype: Plate 3, Figure 2
Paratype: Plate 3, Figure 1
Type Locality: Holotype: late Valanginian, Bed LCH164M, base furcillata ammonite Zone, furcillata Sub-zone, Slide LCH164M/1, E.F. G40.2. Paratype: base Valanginian, Bed B136M, pertransiens ammonite Zone, premolicus Sub-zone, Slide B136M/R1, E.F. C42.2.
Derivation of Name: From the Latin conspicuus, manifest, visible, prominent - in reference to the distinctiveness of this species.
Diagnosis: A relatively large species with an elongate ovoidal body, autocyst only. The epicyst is rounded triangular in outline and the hypocyst may be more broadly rounded or similar to the epicyst. There are no apical or antapical horns and the surface is featureless. Some thinning of the cyst wall is often observed towards the poles. Other than the large single-plate precingular archeopyle (presumed mid dorsal) there is no indication of tabulation.
Dimensions: Holotype 96 × 58 μm.
Paratype 68 × 53 μm.
Overall - 96 (71) 58 μm × 61 (52) 46 μm.
Specimens measured – 25.
Remarks: This species is characterised by its relatively large size and its elongation. There is an increase in size and degree of elongation throughout its long range (it was observed throughout the Vergol and La Charce sections analysed here), and this seems to be a gradual change. Younger specimens are particularly elongate, approaching spindle-shaped (as in the holotype), and can show some "pinching" towards the antapex so that cysts develop a rounded antapical protrusion (see pl. 3, figs. 2-4). The more elongate younger specimens are very similar to that illustrated by Leereveld (1997b, fig. 10a), as Chytroeisphaeridia scabrata Pocock 1972. Leereveld (op. cit.) recorded "C. scabratum" throughout the Hauterivian/Barremian section of Rio Argos but he did not report that species per se in the Rio Argos Tithonian-Valanginian interval (Leereveld 1997a).
Chytroeisphaeridia scabrata Pocock 1972. – LEEREVELD 1997b, fig. 10a.
Holotype: Plate 3, Figure 2
Paratype: Plate 3, Figure 1
Type Locality: Holotype: late Valanginian, Bed LCH164M, base furcillata ammonite Zone, furcillata Sub-zone, Slide LCH164M/1, E.F. G40.2. Paratype: base Valanginian, Bed B136M, pertransiens ammonite Zone, premolicus Sub-zone, Slide B136M/R1, E.F. C42.2.
Derivation of Name: From the Latin conspicuus, manifest, visible, prominent - in reference to the distinctiveness of this species.
Diagnosis: A relatively large species with an elongate ovoidal body, autocyst only. The epicyst is rounded triangular in outline and the hypocyst may be more broadly rounded or similar to the epicyst. There are no apical or antapical horns and the surface is featureless. Some thinning of the cyst wall is often observed towards the poles. Other than the large single-plate precingular archeopyle (presumed mid dorsal) there is no indication of tabulation.
Dimensions: Holotype 96 × 58 μm.
Paratype 68 × 53 μm.
Overall - 96 (71) 58 μm × 61 (52) 46 μm.
Specimens measured – 25.
Remarks: This species is characterised by its relatively large size and its elongation. There is an increase in size and degree of elongation throughout its long range (it was observed throughout the Vergol and La Charce sections analysed here), and this seems to be a gradual change. Younger specimens are particularly elongate, approaching spindle-shaped (as in the holotype), and can show some "pinching" towards the antapex so that cysts develop a rounded antapical protrusion (see pl. 3, figs. 2-4). The more elongate younger specimens are very similar to that illustrated by Leereveld (1997b, fig. 10a), as Chytroeisphaeridia scabrata Pocock 1972. Leereveld (op. cit.) recorded "C. scabratum" throughout the Hauterivian/Barremian section of Rio Argos but he did not report that species per se in the Rio Argos Tithonian-Valanginian interval (Leereveld 1997a).