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Circulodinium brevispinosum
Cyclonephelium brevispinosum, (Pocock, 1962, p.81, pl.14, figs.222-223), Jansonius, 1986, p.204; Emendation: Brideaux, 1977, p.15-16, as Tenua brevispinosa.
Originallv Palaeohystrichophora. subsequently Tenua Eisenack, 1958, thirdly Canningia?, fourthly Cyclonephelium, fifthly (and now) Circulodinium.
Helby, 1987, also transferred this species to Circulodinium.
Brideaux, 1977, emended the diagnosis of this species, as Tenua brevispinosa.
Holotype: Pocock, 1972, pl.14, figs.222, 223; Brideaux, 1977, pl.6, fig.1; Jansonius, 1986, pl.4, fig.6
Paratype: Pocock, 1972
Locus typicus: Imperial Virginia Hills, W Canada
Stratum typicum: 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.
Originallv Palaeohystrichophora. subsequently Tenua Eisenack, 1958, thirdly Canningia?, fourthly Cyclonephelium, fifthly (and now) Circulodinium.
Helby, 1987, also transferred this species to Circulodinium.
Brideaux, 1977, emended the diagnosis of this species, as Tenua brevispinosa.
Holotype: Pocock, 1972, pl.14, figs.222, 223; Brideaux, 1977, pl.6, fig.1; Jansonius, 1986, pl.4, fig.6
Paratype: Pocock, 1972
Locus typicus: Imperial Virginia Hills, W Canada
Stratum typicum: 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.