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Duosphaeridium
From Fensome et al., 2019:
Duosphaeridium, Davey and Williams, 1966b, p.97.
Emendation: Soliman and Fensome, 2019a, p.1302.
Although the "type species" was not validly transferred by Davey and Williams (1966b), the generic name Duosphaeridium was validly published by these authors, since it is based on a previously validly published species name.
Type: Cookson, 1965a, pl.10, fig.1, as Diphyes nudum.
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Original description: [Loeblich and Loeblich, 1968]:
Description:
Proximate cyst composed of two more or less spheroidal parts, neither bearing processes. Anterior part with apical archeopyle. Posterior part similar in shape with small circular antapical opening present.
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Modified description:
Stover and Evitt, 1978, p. 40:
Synopsis:
Cysts proximate, composed of two longitudinally attached, more or less subspherical bodies, one with an apical archeopyle, Type tA.
Description:
Shape: Outline approximates that of the numeral 8; outline in apical-antapical view circular.
Wall relationships: Endophragm and periphragm virtually indistinguishable, except where the latter separates to form the large antapical body.
Wall features: No parasutural features. Periphragmal surface punctoreticulate, finely granular, or rugulate; delicate surface features may be arranged longitudinally.
Paratabulation: Essentially lacking, except for vague indication along archeopyle suture; formula unknown.
Archeopyle: Apical, Type tA; archeopyle suture slightly zigzag; operculum free.
Paracingulum: Not expressed.
Parasulcus: Not expressed.
Size: Small to intermediate.
Affinities:
Duosphaeridium differs from Diphyes in lacking processes on the anterior body and in generally having a much more inflated posterior structure; and from Balcattia in having the wall of the posterior body continuous and smooth or faintly striate. The comparable structure on Balcattia is discontinuous and composed of fibrous strands.
Duosphaeridium, Davey and Williams, 1966b, p.97.
Emendation: Soliman and Fensome, 2019a, p.1302.
Although the "type species" was not validly transferred by Davey and Williams (1966b), the generic name Duosphaeridium was validly published by these authors, since it is based on a previously validly published species name.
Type: Cookson, 1965a, pl.10, fig.1, as Diphyes nudum.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Loeblich and Loeblich, 1968]:
Description:
Proximate cyst composed of two more or less spheroidal parts, neither bearing processes. Anterior part with apical archeopyle. Posterior part similar in shape with small circular antapical opening present.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt, 1978, p. 40:
Synopsis:
Cysts proximate, composed of two longitudinally attached, more or less subspherical bodies, one with an apical archeopyle, Type tA.
Description:
Shape: Outline approximates that of the numeral 8; outline in apical-antapical view circular.
Wall relationships: Endophragm and periphragm virtually indistinguishable, except where the latter separates to form the large antapical body.
Wall features: No parasutural features. Periphragmal surface punctoreticulate, finely granular, or rugulate; delicate surface features may be arranged longitudinally.
Paratabulation: Essentially lacking, except for vague indication along archeopyle suture; formula unknown.
Archeopyle: Apical, Type tA; archeopyle suture slightly zigzag; operculum free.
Paracingulum: Not expressed.
Parasulcus: Not expressed.
Size: Small to intermediate.
Affinities:
Duosphaeridium differs from Diphyes in lacking processes on the anterior body and in generally having a much more inflated posterior structure; and from Balcattia in having the wall of the posterior body continuous and smooth or faintly striate. The comparable structure on Balcattia is discontinuous and composed of fibrous strands.