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Bohaidina laevigata ssp. laevigata
Bohaidina laevigata ssp. laevigata
Autonym.
Lentin and Williams, 1989, 1993, retained this taxon at subspecific rank
Location of horizon of supplemented specimens: Xu Jinli and Mao Shaozhi, 1989, Upper part of the Third Member of the Shahejie Formation, Zhanhua and Kenli Counties, Shandong Province.
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Supplemented description:
Xu Jinli and Mao Shaozhi, 1989:
Description:
Cyst rhombic to ovoid in outline with rounded or slightly extended apex and antapex. Girdle projections 2-3, sometimes discernible in dorsal side. Girdle folds well developed. Wall autophragm, its surface smooth or weakly reticulate under high magnification.
Archeopyle combination, tAa+3Ia type, opercula compound and attached to the cyst in situ.
A weak rupture beneath the apex often shows, indicating the accessory suture separated the apical piece and precingular series.
Tabulation indicated by archeopyle in epitract is 4", 3a, 7"".
Discussion:
The present species was designed as the type species of Bohaidina. The original description (Jiabo, 1978, p.38), however, did not give definite information on archeopyle, instead just stated "possible apical". Re-observation on the holotype (Jiabo, 1978, pl. 13, fig. 1) indicated that the accessory archeopyle suture separated the apical and intercalary series was distinct, the second intercalary plate (2a) moved slightly towards left, and the anterior side of 2a was straight (9µm long), which forms obtuse angles with the two neighbouring sides of 1a and 3a. These features indicate the intercalary series of Bohaidina to be of linteloid type.
Autonym.
Lentin and Williams, 1989, 1993, retained this taxon at subspecific rank
Location of horizon of supplemented specimens: Xu Jinli and Mao Shaozhi, 1989, Upper part of the Third Member of the Shahejie Formation, Zhanhua and Kenli Counties, Shandong Province.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Supplemented description:
Xu Jinli and Mao Shaozhi, 1989:
Description:
Cyst rhombic to ovoid in outline with rounded or slightly extended apex and antapex. Girdle projections 2-3, sometimes discernible in dorsal side. Girdle folds well developed. Wall autophragm, its surface smooth or weakly reticulate under high magnification.
Archeopyle combination, tAa+3Ia type, opercula compound and attached to the cyst in situ.
A weak rupture beneath the apex often shows, indicating the accessory suture separated the apical piece and precingular series.
Tabulation indicated by archeopyle in epitract is 4", 3a, 7"".
Discussion:
The present species was designed as the type species of Bohaidina. The original description (Jiabo, 1978, p.38), however, did not give definite information on archeopyle, instead just stated "possible apical". Re-observation on the holotype (Jiabo, 1978, pl. 13, fig. 1) indicated that the accessory archeopyle suture separated the apical and intercalary series was distinct, the second intercalary plate (2a) moved slightly towards left, and the anterior side of 2a was straight (9µm long), which forms obtuse angles with the two neighbouring sides of 1a and 3a. These features indicate the intercalary series of Bohaidina to be of linteloid type.