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Circulodinium brevispinosum
From Fensome et al., 2019:
Cyclonephelium brevispinosum (Pocock, 1962, p.81, pl.14, figs.222–223) Jansonius, 1986, p.204.
Emendation: Brideaux, 1977, p.15–16, as Tenua brevispinosa.
Holotype: Pocock, 1962, pl.14, fig.222; Jansonius, 1986, pl.4, fig.6; Fauconnier and Masure, 2004, pl.14, figs.7–8.
Originally Palaeohystrichophora, subsequently Tenua Eisenack, thirdly Canningia?, fourthly Cyclonephelium, fifthly Circulodinium. Helby (1987, p.324–325) also proposed this combination.
Taxonomic senior synonym: Tenua hystrix, according to Fensome et al. (2019a, p.48).
Age: Barremian.
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Original description as Palaeohystrichophora brevispinosa: [Pocock, 1972, p. 81]:
Description:
Theca more or less isodiametric, covered by short spines; transverse furrow equatorial, broad, marked by two rows of short spines; epitheca conical, terminated by a tuft of slightly longer spines than those covering the rest of the theca; epitheca terminated by two short blunt processes, one slightly longer and sharper than the other; the theca commonly encloses a spherical cyst about half the diameter of the theca; yellow green spherical organic bodies are also frequently present.
Dimensions:
Size Range: Theca: Width of girdle 69 (98) 110 µm X 110 (114) 120 µm. Spine length: a. at epitheca 5 (6) 7 µm. b. at girdle 3 (3.5) 5 µm. c. body of theca 2 (4) 6 µm. Diameter of cyst 48 (55) 63 µm.
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Supplemental description:
Jansonius, 1986, p. 204:
(Holotype) Overall size 120 x 110 µm; epicyst conical, hypocyst with two blunt protrusions; wall ca. 1 µm thick, light brown, covered by rather densely, if somewhat irregularly distributed verrucae (1-2 x 1-2 µm) that near the periphery grade into rods, spines, or even short muri or membranes up to 5 µm tall, occasionally with solid distal tips or knobs.
An apical archeopyle is delineated by an incipient zig-zag split between apex and shoulder.
Cingulum essentially unmarked, although occasional folds suggest a possible location.
Other such discontinuous folds only hint at a rudimentary paratabulation.
No internal body is present.
Cyclonephelium brevispinosum (Pocock, 1962, p.81, pl.14, figs.222–223) Jansonius, 1986, p.204.
Emendation: Brideaux, 1977, p.15–16, as Tenua brevispinosa.
Holotype: Pocock, 1962, pl.14, fig.222; Jansonius, 1986, pl.4, fig.6; Fauconnier and Masure, 2004, pl.14, figs.7–8.
Originally Palaeohystrichophora, subsequently Tenua Eisenack, thirdly Canningia?, fourthly Cyclonephelium, fifthly Circulodinium. Helby (1987, p.324–325) also proposed this combination.
Taxonomic senior synonym: Tenua hystrix, according to Fensome et al. (2019a, p.48).
Age: Barremian.
---------------------------------------------------------------------------------------------------
Original description as Palaeohystrichophora brevispinosa: [Pocock, 1972, p. 81]:
Description:
Theca more or less isodiametric, covered by short spines; transverse furrow equatorial, broad, marked by two rows of short spines; epitheca conical, terminated by a tuft of slightly longer spines than those covering the rest of the theca; epitheca terminated by two short blunt processes, one slightly longer and sharper than the other; the theca commonly encloses a spherical cyst about half the diameter of the theca; yellow green spherical organic bodies are also frequently present.
Dimensions:
Size Range: Theca: Width of girdle 69 (98) 110 µm X 110 (114) 120 µm. Spine length: a. at epitheca 5 (6) 7 µm. b. at girdle 3 (3.5) 5 µm. c. body of theca 2 (4) 6 µm. Diameter of cyst 48 (55) 63 µm.
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Supplemental description:
Jansonius, 1986, p. 204:
(Holotype) Overall size 120 x 110 µm; epicyst conical, hypocyst with two blunt protrusions; wall ca. 1 µm thick, light brown, covered by rather densely, if somewhat irregularly distributed verrucae (1-2 x 1-2 µm) that near the periphery grade into rods, spines, or even short muri or membranes up to 5 µm tall, occasionally with solid distal tips or knobs.
An apical archeopyle is delineated by an incipient zig-zag split between apex and shoulder.
Cingulum essentially unmarked, although occasional folds suggest a possible location.
Other such discontinuous folds only hint at a rudimentary paratabulation.
No internal body is present.