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Adnatosphaeridium filamentosum

From Fensome et al., 2019:
Adnatosphaeridium filamentosum, (Cookson and Eisenack, 1958, p.47–48, pl.7, figs.8–9; pl.8, figs.1–2) Williams and Downie, 1969, p.17.
Holotype: Cookson and Eisenack, 1958, pl.7, fig.9.
NOW Rigaudella.
Originally Cannosphaeropsis, subsequently Adnatosphaeridium, thirdly (and now) Rigaudella.
Taxonomic junior synonym: Cannosphaeropsis perforata, according to Stancliffe and Sarjeant (1990, p.206). This combination was not validly published in Williams and Downie (1966c, p.218), since these authors did not fully reference the basionym.
Age: Middle -Late Jurassic.

Locus typicus: Carnavron Basin, W Australia

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Original description as Cannosphaeropsis filamentosa: [Cookson and Eisenack, 1958, p. 47]:

Description:
Shell approximately sphaerical, provided with a varying number of thin, solid processes which branch distally, sometimes in a fan-shaped manner, to form by their coalescence an open or sometimes dense enveloping network.

Dimensions:
Holotype - overall diameter 124 µm, shell 48 µm.

Affinities:
C. filamentosa is distinct from C. aemula in that the processes supporting the enveloping network are more uniform in size and never possess the hollow extremities of that species.
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