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Cannosphaeropsis praetexta
Cannosphaeropsis? praetexta, Corradini, 1973
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Cannosphaeropsis.
Holotype: Corradini, 1973, pl.25, figs.7a-b
Locus typicus: Castel di Casio, Bologna, Italy
Stratum typicum: Late Cretaceous-Palaeocene
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Original description: [Corradini, 1973, p. 163]:
Diagnosis:
Ovoidal central body with mostly granular endophragm. Smooth and thin periphragm from which several processes arise, distally interconnected by trabeculae bearing acuminate or capitate spines.
Precingular archeopyle formed by the loss of a dorsal plate.
Description:
The trabeculate cyst is formed by a thick endophragm, sometimes smooth but normally granular, and by a thin and smooth periphragm.
The numerous processes have a fairly broad base, sometimes perforate, and a curved, taeniate or triangular cross-section. They are often flattened distally and connected with the adjacent processes by thin trabeculae forming a true network with irregular meshes around the central body. The trabeculae are thicker near the end of the processes and mostly flattened and bear short, spiny or capitate appendages which adorn like a lace the whole cyst. Rare, thin perforations may occur on the whole trabecular area.
Archeopyle precingular, in form of a triangle with rounded corners.
Dimensions:
Holotype: diameter of the central body 56x70 µm, length of the processes 18-40 µm.
Range: diameter of the central body 46-56x60-72 µm, length of processes 10-40 µm.
Affinities:
C. praetexta is distinguished from previously described species of Cannosphaeropsis by the constant presence of the archeopyle, by having thick central body and a lace-like trabeculation. It is worthwhile mentioning that tubercles arranged in an irregular pattern occur on the central body of some specimens. Also irregular seem to be the arrangement of the processes and their length, which is variable and appears to be higher on the antapical area.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Cannosphaeropsis.
Holotype: Corradini, 1973, pl.25, figs.7a-b
Locus typicus: Castel di Casio, Bologna, Italy
Stratum typicum: Late Cretaceous-Palaeocene
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Corradini, 1973, p. 163]:
Diagnosis:
Ovoidal central body with mostly granular endophragm. Smooth and thin periphragm from which several processes arise, distally interconnected by trabeculae bearing acuminate or capitate spines.
Precingular archeopyle formed by the loss of a dorsal plate.
Description:
The trabeculate cyst is formed by a thick endophragm, sometimes smooth but normally granular, and by a thin and smooth periphragm.
The numerous processes have a fairly broad base, sometimes perforate, and a curved, taeniate or triangular cross-section. They are often flattened distally and connected with the adjacent processes by thin trabeculae forming a true network with irregular meshes around the central body. The trabeculae are thicker near the end of the processes and mostly flattened and bear short, spiny or capitate appendages which adorn like a lace the whole cyst. Rare, thin perforations may occur on the whole trabecular area.
Archeopyle precingular, in form of a triangle with rounded corners.
Dimensions:
Holotype: diameter of the central body 56x70 µm, length of the processes 18-40 µm.
Range: diameter of the central body 46-56x60-72 µm, length of processes 10-40 µm.
Affinities:
C. praetexta is distinguished from previously described species of Cannosphaeropsis by the constant presence of the archeopyle, by having thick central body and a lace-like trabeculation. It is worthwhile mentioning that tubercles arranged in an irregular pattern occur on the central body of some specimens. Also irregular seem to be the arrangement of the processes and their length, which is variable and appears to be higher on the antapical area.