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Circulodinium kukebaiense
From Fensome et al., 2019:
Circulodinium kukebaiense (Mao Shaozhi and Norris, 1988, p.31, pl.1, figs.6–8) He Chengquan et al., 2009, p.271. Holotype: Mao Shaozhi and Norris, 1988, pl.1, fig.7; Fensome et al., 2019a, fig.18G. NOW Tenua Eisenack. Originally Canningia, subsequently Circulodinium, thirdly (and now) Tenua Eisenack. Taxonomic junior synonym (at specific rank): Cyclonephelium distinctum var. psilatum, according to Fensome et al. (2019a, p.48–49). Age: Turonian–Santonian.
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Original description: [Mao Shaozhi and Norris, 1988, p. 31]:
Diagnosis:
Cyst proximate, in dorsoventral view typically broadly ellipsoidal. Apical prominence protruding slightly from outline in one end; antapical end rounded or weakly diverging into two blunt lobations.
Autophragm thin, granulate, with numerous short nontabular isolated spines.
Archeopyle apical, type (tA)a or (tA).
Description:
Cyst subspherical to broadly ellipsoidal. Length and breadth of cyst almost equal, or latter slightly longer. Apical prominence short (1 to 3 µm), protruding indistinctly from outline. Antapex rounded or with slight concavity between two weak antapical lobations.
Autophragm thin and readily folded, folds usually trending approximately parallel to margin of cyst. Granulate wall surface covered with simple solid acuminate spines, 1 to 5 µm long, 1 to 2 µm across at their bases, and spaced 3 to 6 µm apart.
Archeopyle suture a zigzag line, with accessory sutures indicating six precingular plates. Operculum typically but not consistently attached. Cingulum usually indiscernible.
Sulcal notch offset to the left.
Indication of tabulation, other than archeopyle, absent.
Dimensions:
Length (including operculum) 46 to 54 µm (holotype 48 µm), width 45 to 61 µm (holotype 58 µm).
Affinities:
Canningia kukebaiensis differs from some other species of Canningia in having a subspherical to broadly ellipsoidal cyst with a small indistinct apical prominence and in its possession of a granulate autophragm covered with short, isolated, solid, and acuminate spines. C. colliveri (Cookson and Eisenack, 1960) has a cyst somewhat longer than broad, and its surface is granular or closely to sparsely spinate. C. minor (Cookson and Hughes, 1964) has a scabrate rather than granulate and spinate surface. C. scabrosa (Cookson and Eisenack, 1970) differs from C. kukebaiensis in having an irregular outline and some very short and narrow hairlike appendages.
Circulodinium kukebaiense (Mao Shaozhi and Norris, 1988, p.31, pl.1, figs.6–8) He Chengquan et al., 2009, p.271. Holotype: Mao Shaozhi and Norris, 1988, pl.1, fig.7; Fensome et al., 2019a, fig.18G. NOW Tenua Eisenack. Originally Canningia, subsequently Circulodinium, thirdly (and now) Tenua Eisenack. Taxonomic junior synonym (at specific rank): Cyclonephelium distinctum var. psilatum, according to Fensome et al. (2019a, p.48–49). Age: Turonian–Santonian.
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Original description: [Mao Shaozhi and Norris, 1988, p. 31]:
Diagnosis:
Cyst proximate, in dorsoventral view typically broadly ellipsoidal. Apical prominence protruding slightly from outline in one end; antapical end rounded or weakly diverging into two blunt lobations.
Autophragm thin, granulate, with numerous short nontabular isolated spines.
Archeopyle apical, type (tA)a or (tA).
Description:
Cyst subspherical to broadly ellipsoidal. Length and breadth of cyst almost equal, or latter slightly longer. Apical prominence short (1 to 3 µm), protruding indistinctly from outline. Antapex rounded or with slight concavity between two weak antapical lobations.
Autophragm thin and readily folded, folds usually trending approximately parallel to margin of cyst. Granulate wall surface covered with simple solid acuminate spines, 1 to 5 µm long, 1 to 2 µm across at their bases, and spaced 3 to 6 µm apart.
Archeopyle suture a zigzag line, with accessory sutures indicating six precingular plates. Operculum typically but not consistently attached. Cingulum usually indiscernible.
Sulcal notch offset to the left.
Indication of tabulation, other than archeopyle, absent.
Dimensions:
Length (including operculum) 46 to 54 µm (holotype 48 µm), width 45 to 61 µm (holotype 58 µm).
Affinities:
Canningia kukebaiensis differs from some other species of Canningia in having a subspherical to broadly ellipsoidal cyst with a small indistinct apical prominence and in its possession of a granulate autophragm covered with short, isolated, solid, and acuminate spines. C. colliveri (Cookson and Eisenack, 1960) has a cyst somewhat longer than broad, and its surface is granular or closely to sparsely spinate. C. minor (Cookson and Hughes, 1964) has a scabrate rather than granulate and spinate surface. C. scabrosa (Cookson and Eisenack, 1970) differs from C. kukebaiensis in having an irregular outline and some very short and narrow hairlike appendages.