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Valensiella griphus
From Fensome et al., 2019:
Valensiella griphus Norvick, 1975, p.75–76, pl.8, figs.6–7; pl.10, figs.7–9.
Holotype: Norvick, 1975, pl.10, figs.7–8. NIA.
Locus typicus: Bathurst Island no. 2 well, Australia
Stratum typicum: Cenomanian
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Original diagnosis: Norvick, 1976, p.75
Cyst proximate, acavate, spherical or subspherical. Wall thin, covered by a coarse, non-tabulate reticulum of low, solid ridges. Lumina rarely interconnected, Ridges support a thin, fragile, finely reticulate, non-tabulate, distal membrane, which encloses the entire tract. Tabulation and cingulum absent. Archaeopyle apical, tetratabular, with a notched margin.
Description: Norvick, 1976, p.75-76
Proximate acavate cyst, with a spherical or subspherical tract. Some examples are dorsoventrally flattened, probably because of secondary distortion. The cyst wall is less than 0.5 µm thick and its surface is traversed by a network of solid ridges. The ridges or muri are 1 to 1.5 µm in thickness and are distally expanded, so that in optical section they have the appearance of short, stout processes. They are 2 to 3 µm in height, and form a reticulum whose lumina are occasionally interconnected and are about 5 to 10 µm in diameter. Free-standing processes and unattached ridges are rare. The network of ridges supports a very thin and fragile reticulate membrane over the whole surface of the cyst. The reticulum consists of circular or polygonal perforations 0.5 to 1 µm in diameter, leaving strands 0.5 to 1 µm in width. Neither the proximal (coarse) nor the distal (fine) reticula reflect any trace of tabulation. The archaeopyle is apical and in one specimen is attached by a sulcal neck. In dehisced specimens the archaeopyle margin is slightly zig-zag and often notched.
Dimensions: The overall width ranges between 47 and 71 µm with an average of 56 µm for 16 specimens.
Valensiella griphus Norvick, 1975, p.75–76, pl.8, figs.6–7; pl.10, figs.7–9.
Holotype: Norvick, 1975, pl.10, figs.7–8. NIA.
Locus typicus: Bathurst Island no. 2 well, Australia
Stratum typicum: Cenomanian
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Original diagnosis: Norvick, 1976, p.75
Cyst proximate, acavate, spherical or subspherical. Wall thin, covered by a coarse, non-tabulate reticulum of low, solid ridges. Lumina rarely interconnected, Ridges support a thin, fragile, finely reticulate, non-tabulate, distal membrane, which encloses the entire tract. Tabulation and cingulum absent. Archaeopyle apical, tetratabular, with a notched margin.
Description: Norvick, 1976, p.75-76
Proximate acavate cyst, with a spherical or subspherical tract. Some examples are dorsoventrally flattened, probably because of secondary distortion. The cyst wall is less than 0.5 µm thick and its surface is traversed by a network of solid ridges. The ridges or muri are 1 to 1.5 µm in thickness and are distally expanded, so that in optical section they have the appearance of short, stout processes. They are 2 to 3 µm in height, and form a reticulum whose lumina are occasionally interconnected and are about 5 to 10 µm in diameter. Free-standing processes and unattached ridges are rare. The network of ridges supports a very thin and fragile reticulate membrane over the whole surface of the cyst. The reticulum consists of circular or polygonal perforations 0.5 to 1 µm in diameter, leaving strands 0.5 to 1 µm in width. Neither the proximal (coarse) nor the distal (fine) reticula reflect any trace of tabulation. The archaeopyle is apical and in one specimen is attached by a sulcal neck. In dehisced specimens the archaeopyle margin is slightly zig-zag and often notched.
Dimensions: The overall width ranges between 47 and 71 µm with an average of 56 µm for 16 specimens.