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Trichodinium ciliatum
From Fensome et al., 2019:
Trichodinium ciliatum (Gocht, 1959, p.65, pl.8, figs.5–6) Eisenack and Klement, 1964, p.811.
Holotype: Gocht, 1959, pl.8, fig.5; Jan du Chêne et al., 1986a, pl.121, figs.9–13.
NOW Elimatia. Originally Apteodinium, subsequently Trichodinium, thirdly (and now) Elimatia.
Taxonomic junior synonym: Trichodinium castanea, by implication in Clarke and Verdier (1967, p.19), who believed Trichodinium castanea to be the senior name — however, Harding (1990b, p.38) retained the two species.
Age: late Hauterivian.
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Original description (Gocht, 1959) [translation PKB 2024]:
The form already described in Part I fits so well with the other Apteodinium species that it should be included in the genus.
Type: The specimen shown in Plate 8, Fig. 5 and preserved in specimen N103.
Locus typicus: Rühlertwist 3 borehole (Emsland).
Stratum typicum: Upper Hauterive 3/4.
Diagnosis: Carapace spherical to ovoid, not very thick-walled, with numerous fine bristles all around. No furrows. Apex often indicated by individual larger processes or processes that have grown together to form a short skin-like projection. Hatching openings frequent, trapezoidal to triangular, sometimes expanded towards the sides at the lower edge or tearing the carapace in a semicircle. Additions: The species resembles a form that Deflandre described as Palaeoperidnium castanea from chalk guns. P. castanea has a similar habit and set of bristles, with enlarged processes also indicating the apex. It also has a belt and longitudinal furrow, which are certainly missing in Apteodinium ciliatum.
Dimensions: Type 78:64 µ, apical projection 8 µ, extensions around 4 µ. other specimens are 48-86 long. Fabric: 25 copies from sample 9, 3 more from sample 12.
Remarks:
Harding, 1990, p.38: This species is of great stratigraphic value as it occurs in rocks of Hauterivian and earliest Barremian age, but disappears before the advent of the Hauptblatterton and equivalent facies. It is easily distinguished from other species of the genus by its subcircular ambitus and dense, even cover of evexate tubercles (1-2 µm long) formed by the fusion of the fibres forming an open reticulum on the distal surface of the differentiated autophragm. An apical tuft of longer tubercles is occasionally present but no true horn develops. Paratabulation is obscure but is consistent with an L-type sexiform gonyaulacoid format as far as can be discerned. Paracingulum often expressed by rows of longer tubercles. Parasulcal area and IV are sometimes less densely spinose. Flagellar scar present.
Dimensions: Length (72) 63 (48) µm. Width (68) 60 (50) µm. Specimens = 32 (18).
Trichodinium ciliatum (Gocht, 1959, p.65, pl.8, figs.5–6) Eisenack and Klement, 1964, p.811.
Holotype: Gocht, 1959, pl.8, fig.5; Jan du Chêne et al., 1986a, pl.121, figs.9–13.
NOW Elimatia. Originally Apteodinium, subsequently Trichodinium, thirdly (and now) Elimatia.
Taxonomic junior synonym: Trichodinium castanea, by implication in Clarke and Verdier (1967, p.19), who believed Trichodinium castanea to be the senior name — however, Harding (1990b, p.38) retained the two species.
Age: late Hauterivian.
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Original description (Gocht, 1959) [translation PKB 2024]:
The form already described in Part I fits so well with the other Apteodinium species that it should be included in the genus.
Type: The specimen shown in Plate 8, Fig. 5 and preserved in specimen N103.
Locus typicus: Rühlertwist 3 borehole (Emsland).
Stratum typicum: Upper Hauterive 3/4.
Diagnosis: Carapace spherical to ovoid, not very thick-walled, with numerous fine bristles all around. No furrows. Apex often indicated by individual larger processes or processes that have grown together to form a short skin-like projection. Hatching openings frequent, trapezoidal to triangular, sometimes expanded towards the sides at the lower edge or tearing the carapace in a semicircle. Additions: The species resembles a form that Deflandre described as Palaeoperidnium castanea from chalk guns. P. castanea has a similar habit and set of bristles, with enlarged processes also indicating the apex. It also has a belt and longitudinal furrow, which are certainly missing in Apteodinium ciliatum.
Dimensions: Type 78:64 µ, apical projection 8 µ, extensions around 4 µ. other specimens are 48-86 long. Fabric: 25 copies from sample 9, 3 more from sample 12.
Remarks:
Harding, 1990, p.38: This species is of great stratigraphic value as it occurs in rocks of Hauterivian and earliest Barremian age, but disappears before the advent of the Hauptblatterton and equivalent facies. It is easily distinguished from other species of the genus by its subcircular ambitus and dense, even cover of evexate tubercles (1-2 µm long) formed by the fusion of the fibres forming an open reticulum on the distal surface of the differentiated autophragm. An apical tuft of longer tubercles is occasionally present but no true horn develops. Paratabulation is obscure but is consistent with an L-type sexiform gonyaulacoid format as far as can be discerned. Paracingulum often expressed by rows of longer tubercles. Parasulcal area and IV are sometimes less densely spinose. Flagellar scar present.
Dimensions: Length (72) 63 (48) µm. Width (68) 60 (50) µm. Specimens = 32 (18).