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Batiacasphaera mica

Batiacasphaera mica Harding, 1990b, p. 48, pl.25, figs.10-19 ex Harding in Williams et al., 1998, p.67.

Name not validly published since lodgment of holotype not specified.

Holotype: Harding, 1990, pl.25, fig.10
Locus typicus: Otto Gott Claypit, Lower Saxony, Germany
Stratum typicum: Barremian

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Original description: [Harding, 1990, p. 48]:

Diagnosis:
Shape: Ambitus subcircular, varying from slightly oblate to slightly prolate in shape. Epicyst and hypocyst of approximately equal lengths. Greatest width across paracingular region. Moderate to strong dorso-ventral compression.
Phragma: Autophragm up to 1 µm thick, surface microgranular. Granules vary in size on individual specimens - often coarser along paracingular margins and at the antapex.
ParatabuIation: Complete paratabulation unknown, but epicystal tabulation as shown by archaeopyle sutures: 4", 6", ai. A/l i parasuture anterior to l u/ai.
Archaeopyle: Type (tA), involving four apical paraplates as a free, simple, polyplacoid operculum sometimes adherent. Accessory archaeopyle sutures formed in precingular series.
Paracingulum: Rarely expressed, but may be present as an equatorial band conspicuous for its reduced ornamentation.
Parasulcus: Rare specimens show flagellar scar, more usually the only indication is the position of ai.

Dimensions:
Diameter (60) 47.5 (30) µm. Specimens = 29 (20).

Affinities:
The granulation of the cyst body varies from being equidimensional over the whole cyst surface, to being much coarser along parasutures. Those specimens with coarse granulation have thicker walls.
This species is distinguished from Kallosphaeridium by the free rather than adnate nature of the operculum. It differs from B. macrogranulata Morgan 1975 in having a more subcircular ambitus and having less evenly distributed granulation and from B. saidensis Below 1981 in being smaller and having smaller granulae.
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