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Oligosphaeridium verrucosum
Oligosphaeridium verrucosum Davey, 1979b, p.558, pl.5, figs.1–3. Holotype: Davey, 1979b, pl.5, figs.1–2; Fauconnier and Masure, 2004, pl.61, figs.6–9. Age: late Aptian.
Original description: Davey 1979, p. 558.
Diagnosis: A large subspherical species of Oligosphaeridium composed of a relatively thick periphragm which is discretely granular on the endocyst, but is smooth when it forms the processes. The latter are tubiform and distally terminate with a rather irregular secate-aculeate margin. The processes vary only slightly in size except the parasulcal and posterior intercalary (1p) processes which are noticeably smaller. The endophragm is smooth beneath the processes. The apical archeopyle is usually developed and has a pronounced zig-zag margin and a deep parasulcal notch.
Dimensions: Range: Endocyst length (archaeopyle developed): 50-57 µm; Endocyst width: 50-64 µm; Length of processes: 28-41 µm; medial width of processes: 3-8 µm.
Description: The cyst wall varies from lightly to densely granular and, when the latter, the granules tend to be aligned on either side of the pre- and postcingular paraplate boundaries. Wall thickness varies up to 2µ. The processes are strongly developed and sometimes appears to be fibrous. A smooth circular portion of endophragm is exposed beneath each process.
Original description: Davey 1979, p. 558.
Diagnosis: A large subspherical species of Oligosphaeridium composed of a relatively thick periphragm which is discretely granular on the endocyst, but is smooth when it forms the processes. The latter are tubiform and distally terminate with a rather irregular secate-aculeate margin. The processes vary only slightly in size except the parasulcal and posterior intercalary (1p) processes which are noticeably smaller. The endophragm is smooth beneath the processes. The apical archeopyle is usually developed and has a pronounced zig-zag margin and a deep parasulcal notch.
Dimensions: Range: Endocyst length (archaeopyle developed): 50-57 µm; Endocyst width: 50-64 µm; Length of processes: 28-41 µm; medial width of processes: 3-8 µm.
Description: The cyst wall varies from lightly to densely granular and, when the latter, the granules tend to be aligned on either side of the pre- and postcingular paraplate boundaries. Wall thickness varies up to 2µ. The processes are strongly developed and sometimes appears to be fibrous. A smooth circular portion of endophragm is exposed beneath each process.