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Cannosphaeropsis densa
Cannosphaeropsis densa, Cookson and Eisenack, 1962
Stover and Evitt, 1978, considered this to be a problematical species of Cannosphaeropsis.
Holotype: Cookson and Eisenack, 1962, pl.4, fig.1
Age and occurrence: (?)Upper Albian-Cenomanian: Osborne formation, Fremantle Traffic Bridge bore No. 1 at 100 ft.
Age: Late Albian-Cenomanian
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Original description: [Cookson and Eisenack, 1962b, p. 493]:
Description:
Shell circular in outline, completely covered by a dense network of fine threads of approximately equal thickness. The network appears to have resulted from the distal branching of very numerous and closely approximated radial threads and the irregular anastomosis of their secondary branches. The small meshes so formed are irregular in both size and shape, and their walls have wavy outlines. At the periphery of the network, some of the threads bear short, straight or curved spine-like branches (pl. 4, fig. 3).
Dimensions:
Holotype: Over-all diameter 107 µm; diameter of shell ca. 65 µm.
A paratype: Over-all diameter ca. 102 x 112 µm; shell ca. 60 x 67 µm.
Remarks:
Of the known species of Cannosphaeropsis, C. densa seems most closely related to C. hyperacantha Cookson and Eisenack (1960a, p. 9), from the Senonian Toolonga calcilutite of Western Australia. The chief differences are the even denser form of the enveloping network and the restriction of the spine-like branches to the periphery in C. densa.
Stover and Evitt, 1978, considered this to be a problematical species of Cannosphaeropsis.
Holotype: Cookson and Eisenack, 1962, pl.4, fig.1
Age and occurrence: (?)Upper Albian-Cenomanian: Osborne formation, Fremantle Traffic Bridge bore No. 1 at 100 ft.
Age: Late Albian-Cenomanian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Cookson and Eisenack, 1962b, p. 493]:
Description:
Shell circular in outline, completely covered by a dense network of fine threads of approximately equal thickness. The network appears to have resulted from the distal branching of very numerous and closely approximated radial threads and the irregular anastomosis of their secondary branches. The small meshes so formed are irregular in both size and shape, and their walls have wavy outlines. At the periphery of the network, some of the threads bear short, straight or curved spine-like branches (pl. 4, fig. 3).
Dimensions:
Holotype: Over-all diameter 107 µm; diameter of shell ca. 65 µm.
A paratype: Over-all diameter ca. 102 x 112 µm; shell ca. 60 x 67 µm.
Remarks:
Of the known species of Cannosphaeropsis, C. densa seems most closely related to C. hyperacantha Cookson and Eisenack (1960a, p. 9), from the Senonian Toolonga calcilutite of Western Australia. The chief differences are the even denser form of the enveloping network and the restriction of the spine-like branches to the periphery in C. densa.