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Batiacasphaera macrogranulata

Batiacasphaera macrogranulata, Morgan, 1975

Holotype: Morgan 1975: Plate II, figure 3a-d
Locus typicus: Great Australian basin, Australia
Stratum typicum: C. stylosus zone, Neocomian
Age: Neocomian

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Original description: [Morgan 1975, p. 162]:

Description:
In dorso-ventral view, specimens are subcircular in outline, lacking an apical protrusion.
Autophragm bears a medium dense cover of low, flat, solid, granulae, that are about 1.5 µm in diameter, or has short rugulae formed by the coalescing of two or more adjacent granulae. The density of granulae is variable; some specimens bear mostly granulae and few rugulae, while others bear almost entirely rugulae. The surface between the granulae or rugulae is psilate.
The archeopyle is apical, type A, operculum free; the six precingular reflected plates and the sulcal notch are distinguishable by the partial opening of the accessory archeopyle sutures.
The sulcal notch is always offset from the midline, as the shape of the cyst is lenticular.

Dimensions:
Holotype: 60 µm long and 69 µm broad 49 (53) 60 µm long and 49 (55) 69 µm broad (10 specimens measured).

Comparison:
The new species differs from Batiacasphaera compta Drugg 1970, which has fine reticulate to foveolate ornament, and from Batiacasphaera baculata Drugg 1970, which has fine granulae and rod-like tuberculae covering the surface.

Remark/Comment:
The new species is common in assemblages lacking other dinoflagellates or containing only a few other forms. With only superficial examination it may be misidentified as a damaged baculate spore.
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