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Bosedinia laevigata
Bosedinia laevigata, (Jiabo, 1978 ex He Chengquan and Qian Zeshu, 1979), He Chengquan, 1984
Originally Palaeostomocystis laevigata (name illegitimate), subsequently Bosea laevigata, thirdly (and now) Bosedinia laevigata; see also Fromea laevigata (name illegitimate) and Fromea psilata (name illegitimate).
According to Chen et al., 1988, Jiabo, 1978, did not designate a holotype for this species; however, they illustrated only one specimen.
Holotype: Jiabo, 1978, pl.32, fig.23
Occurrence: second member of the Dongying Formation of the Upper Oligocene Series in the coastal area of the Bohai Sea.
Age: Early Tertiary
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Description as Bosea laevigata: [He Chengquan and Qian Zeshu, 1979]:
Description:
The ambital outline of the tract is ovoidal or subcircular to rounded triangular.
The tract possesses a "pylome" (the opening shown in Fig. 8 appears to be angular), which is usually situated at the broadest part of the tract; the operculum is either attached or lost.
No apical or antapical horns are observed, nor a cingulum or tabulation.
The hypotract is larger than the epitract. The wall of the tract is relatively thin, as it measures approximately 1.2 µm in thickness; it is divided into two layers that are more or less equally thick; the surface of the wall is almost smooth and often bears folds. [The tract] may contain a yellow-coloured structure suggestive of a nucleus. The diameter of the tract ranges from 35 - 60 µm.
Originally Palaeostomocystis laevigata (name illegitimate), subsequently Bosea laevigata, thirdly (and now) Bosedinia laevigata; see also Fromea laevigata (name illegitimate) and Fromea psilata (name illegitimate).
According to Chen et al., 1988, Jiabo, 1978, did not designate a holotype for this species; however, they illustrated only one specimen.
Holotype: Jiabo, 1978, pl.32, fig.23
Occurrence: second member of the Dongying Formation of the Upper Oligocene Series in the coastal area of the Bohai Sea.
Age: Early Tertiary
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Description as Bosea laevigata: [He Chengquan and Qian Zeshu, 1979]:
Description:
The ambital outline of the tract is ovoidal or subcircular to rounded triangular.
The tract possesses a "pylome" (the opening shown in Fig. 8 appears to be angular), which is usually situated at the broadest part of the tract; the operculum is either attached or lost.
No apical or antapical horns are observed, nor a cingulum or tabulation.
The hypotract is larger than the epitract. The wall of the tract is relatively thin, as it measures approximately 1.2 µm in thickness; it is divided into two layers that are more or less equally thick; the surface of the wall is almost smooth and often bears folds. [The tract] may contain a yellow-coloured structure suggestive of a nucleus. The diameter of the tract ranges from 35 - 60 µm.