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Emmetrocysta fibrospinosa

Emmetrocysta? fibrospinosa (Davey and Williams, 1966) Sarjeant, 1981; Emendation: Davey, 1969c, p.36, as a revised diagnosis for Cordosphaeridium fibrospinosum.

NOW Cordosphaeridium. Originally (and now) Cordosphaeridium, subsequently Emmetrocysta?, thirdly Tityrosphaeridium?. Questionable assignment: Sarjeant (1981, p.123).
Taxonomic junior synonyms: Cordosphaeridium exilimurum and Achomosphaera (subsequently Cordosphaeridium) valianta, both according to Fensome et al. (2009, p.23).

Holotype: Davey and Williams 1966, pl.5, fig.5; Bujak et al., 1980, pl.7, figs.3,6
Locus typicus: Enborne, Berkshire, England
Stratum typicum: Early Eocene

Original diagnosis: Davey and Williams, 1966, p. 86: Cordosphaeridium fibrospinosum
Ovoidal central body with wall up to 5 µm thick, composed of smooth endophragm and fibrous periphragm. Processes fibrous, often very broad and ovoidal in cross-section, walls perforate. Processes open distally, with entire or undulose margin. One process per plate reflecting a tabulation typical of genus. Archaeopyle apical haplotabular.

Original description: Davey and Williams, 1966, p. 86: Cordosphaeridium fibrospinosum
This species is characterized by fibrous, often perforate, processes which can be latispinous. The perforations show no regularity in arrangement and tend to be elongate. The cross-section of the processes is ovoidal or rarely cylindrical and then only in the narrower processes. The lengths of the processes vary considerably in different specimens but rarely exceed half the diameter of the central body. It should be noted that in the broader processes, the width often exceeds the length.
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