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Circulodinium densebarbatum
From Fensome et al., 2019:
Circulodinium densebarbatum (Cookson and Eisenack, 1960b, p.253, pl.38, figs.9–10) Fauconnier in Fauconnier and Masure, 2004, p.114.
Holotype: Cookson and Eisenack, 1960b, pl.38, fig.10; Fauconnier and Masure, 2004, pl.14, figs.3–4; Fensome et al., 2019a, fig.18C.
NOW Tenua Eisenack. Originally Cyclonephelium, subsequently Circulodinium, thirdly (and now) Tenua Eisenack.
Age: Tithonian.
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Original description: [Cookson and Eisenack, 1960, p. 253]:
Description:
Shell flat, circular to slightly polyedral with a broad (c.16-24 µm) peripheral zone, ornamented on both sides with short, densely arranged, rod-shaped bristles, ranging from c.2-12 µm in length, with simple, usually capitate or sometimes bifurcate ends, and inner areas without bristles but with granular surfaces. A transverse "girdle" is sometimes evident; a large, terminal pylome results from the complete detachment of the apical region.
Dimensions:
holotype - shell 95 µm long, 92 µm broad, overall 100x98 µm. Range - overall diameter 86-114 µm.
Affinities:
C. densebarbatum differs from C. distinctum Defl. and Cookson, the species of Cyclonephelium to which it is most closely similar, in the stouter nature of the shell and the much denser arrangement of the bristles. The examples from the Wallal deposits on the whole have longer bristles, especially at the antapical region, than those from Broome and Roebuck Bay deposits.
Circulodinium densebarbatum (Cookson and Eisenack, 1960b, p.253, pl.38, figs.9–10) Fauconnier in Fauconnier and Masure, 2004, p.114.
Holotype: Cookson and Eisenack, 1960b, pl.38, fig.10; Fauconnier and Masure, 2004, pl.14, figs.3–4; Fensome et al., 2019a, fig.18C.
NOW Tenua Eisenack. Originally Cyclonephelium, subsequently Circulodinium, thirdly (and now) Tenua Eisenack.
Age: Tithonian.
---------------------------------------------------------------------------------------------------
Original description: [Cookson and Eisenack, 1960, p. 253]:
Description:
Shell flat, circular to slightly polyedral with a broad (c.16-24 µm) peripheral zone, ornamented on both sides with short, densely arranged, rod-shaped bristles, ranging from c.2-12 µm in length, with simple, usually capitate or sometimes bifurcate ends, and inner areas without bristles but with granular surfaces. A transverse "girdle" is sometimes evident; a large, terminal pylome results from the complete detachment of the apical region.
Dimensions:
holotype - shell 95 µm long, 92 µm broad, overall 100x98 µm. Range - overall diameter 86-114 µm.
Affinities:
C. densebarbatum differs from C. distinctum Defl. and Cookson, the species of Cyclonephelium to which it is most closely similar, in the stouter nature of the shell and the much denser arrangement of the bristles. The examples from the Wallal deposits on the whole have longer bristles, especially at the antapical region, than those from Broome and Roebuck Bay deposits.