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Rivernookia
From Williams et al., 2017:
[Rivernookia, Cookson and Eisenack, 1982, p. 56
Type species: originally as Baltisphaeridium septata, Cookson and Eisenack, 1967b (pl.42, fig.6)] ; Rivernookia septata, (Cookson and Eisenack, 1967), Cookson and Eisenack, 1982
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Original description: [Cookson and Eisenack, 1982]:
Description:
Small circular discs; originally hollow spheres with a proportionally thick alveolate wall, without tabulation, with radially positioned, hollow, yet septate processes whose ends are simple or repeatedly and widely branched.
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Stover and Williams, 1987, p. 195:
Affinities:
The reasons given by Cookson and Eisenack (1982, p. 57) for regarding Rivernookia septata as an acritarch (described originally as Baltisphaeridium septatum by Cookson and Eisenack 1967, and subsequently transferred to Spiniferites by McLean 1971, then to Hafniasphaera by Hansen 1977, and then to Achomosphaera by Stover and Evitt 1978) were based largely on difficulties in discerning morphological details on the type specimens. The dark red staining of those specimens enhanced the septate, bubble-like features of the processes, but obscured other features, especially those of the cyst body. Unstained or lightly stained specimens from southeastern Australia and elsewhere show faint parasutural ridges connecting the bases of gonal processes and on some Australian specimens, a precingular (3") archeopyle is evident For additional information see Hafniasphaera Hansen 1977.
[Rivernookia, Cookson and Eisenack, 1982, p. 56
Type species: originally as Baltisphaeridium septata, Cookson and Eisenack, 1967b (pl.42, fig.6)] ; Rivernookia septata, (Cookson and Eisenack, 1967), Cookson and Eisenack, 1982
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Original description: [Cookson and Eisenack, 1982]:
Description:
Small circular discs; originally hollow spheres with a proportionally thick alveolate wall, without tabulation, with radially positioned, hollow, yet septate processes whose ends are simple or repeatedly and widely branched.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Stover and Williams, 1987, p. 195:
Affinities:
The reasons given by Cookson and Eisenack (1982, p. 57) for regarding Rivernookia septata as an acritarch (described originally as Baltisphaeridium septatum by Cookson and Eisenack 1967, and subsequently transferred to Spiniferites by McLean 1971, then to Hafniasphaera by Hansen 1977, and then to Achomosphaera by Stover and Evitt 1978) were based largely on difficulties in discerning morphological details on the type specimens. The dark red staining of those specimens enhanced the septate, bubble-like features of the processes, but obscured other features, especially those of the cyst body. Unstained or lightly stained specimens from southeastern Australia and elsewhere show faint parasutural ridges connecting the bases of gonal processes and on some Australian specimens, a precingular (3") archeopyle is evident For additional information see Hafniasphaera Hansen 1977.