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Agerasphaera circumtabulata

Agerasphaera circumtabulata, (Drugg, 1967), Harland, 1979a, p. 29

Combination illegitimate since the generic name Agerasphaera is illegitimate.
NOW Alisocysta. Originally Eisenackia, subsequently Hystrichokolpoma, thirdly (and now) Alisocysta, fourthly Agerasphaera (name illegitimate).
Taxonomic junior synonym: Hystrichokolpoma mentitum, according to Schumacker-Lambry (1978, p.42) — however, Lentin and Williams (1981, p.135) retained Hystrichokolpoma mentitum.

Holotype: Drugg, 1967, pl.1, fig.12; Damassa, 1979b, pl.3, figs.14–16; Fensome et al., 1993a, fig.1 — p.1061.
Paratype: Drugg, 1967
Locus typicus: Escarpado Canyon, California, U.S.A.
Stratum typicum: Danian

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Original description as Eisenackia circumtabulata: [Drugg, W. 1967, p. 15]:

Diagnosis:
Test ellipsoidal in outline, somewhat compressed. Wall thick, very finely punctate on some specimens. The plates are delineated by low membranous walls. The tabulation is identical to that of Eisenackia crassitabulata Deflandre and Cookson 1955. The test opens by means of an apical operculum.

Dimensions:
Size range, 36 to 47 µm wide, 37 to 47 µm high (six specimens).

Affinities:
This species differs from Eisenackia crassitabulata in that the plates are marked by raised walls, the interiors of which are not filled with a thick-walled mesh.
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