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Bohaidina dorsiprominentis
Bohaidina dorsiprominentis, Jiabo, 1978; emend. Xu Jinli and Mao Shaozhi, 1989
Originally (and now) Bohaidina, subsequently Bohaidina?.
Chen et al., 1988, provisionally included this species in Bohaidina; however, Xu Jinli and Mao Shaozhi (1989, p.219) included the species in Bohaidina without question.
Holotype: Jiabo, 1978, pl.15, figs.1a-e.
Location and horizon of supplemented specimens: Xu Jinli and Mao Shaozhi, 1989, Upper part of the Third Member of the Shahejie Formation, Zhanhua County, Shandong Province.
Age: Early Tertiary
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Emended description:
Xu Jinli and Mao Shaozhi, 1989: (Provisional translation by GSC: courtesy R. Fensome):
Description:
Cyst polyhedral, rhombic in outline. Both apex and antapex extended, and four lateral sides concave, sometimes with an antapical spine of about 3 µm long (pl. II, fig. 7). Girdle projections developed well, hemispherical to short cylindric, one in dorsal side more projected than the other two in ventral side. Wall autophragm, fine-reticulate under high magnification.
Archeopyle combination of tAa+3Ia type, opercula compound. Apical piece fallen towards ventral side evidently and attached to the cyst ventrally. The three intercalary plates are separated from the apical piece by accessory archeopyle suture with their anterior margin warped, displaced or wrenched.
Discussion:
The holotype (Jiabo, 1978, pl. 15, fig. 1a-c) shows distinct archeopyle; the displaced three intercalary plates seem to seem to give a 3I type impression, but the apical series in lateral view falling towards the ventral sides. This peculiar feature observed again this time from two specimens in lateral view has confirmed the archeopyle of B. dorsiprominentis to be of combination type rather than tA or 3I type. It differs from B. alveolae in having only girdle projection in dorsal side and finer ornamentation.
Originally (and now) Bohaidina, subsequently Bohaidina?.
Chen et al., 1988, provisionally included this species in Bohaidina; however, Xu Jinli and Mao Shaozhi (1989, p.219) included the species in Bohaidina without question.
Holotype: Jiabo, 1978, pl.15, figs.1a-e.
Location and horizon of supplemented specimens: Xu Jinli and Mao Shaozhi, 1989, Upper part of the Third Member of the Shahejie Formation, Zhanhua County, Shandong Province.
Age: Early Tertiary
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description:
Xu Jinli and Mao Shaozhi, 1989: (Provisional translation by GSC: courtesy R. Fensome):
Description:
Cyst polyhedral, rhombic in outline. Both apex and antapex extended, and four lateral sides concave, sometimes with an antapical spine of about 3 µm long (pl. II, fig. 7). Girdle projections developed well, hemispherical to short cylindric, one in dorsal side more projected than the other two in ventral side. Wall autophragm, fine-reticulate under high magnification.
Archeopyle combination of tAa+3Ia type, opercula compound. Apical piece fallen towards ventral side evidently and attached to the cyst ventrally. The three intercalary plates are separated from the apical piece by accessory archeopyle suture with their anterior margin warped, displaced or wrenched.
Discussion:
The holotype (Jiabo, 1978, pl. 15, fig. 1a-c) shows distinct archeopyle; the displaced three intercalary plates seem to seem to give a 3I type impression, but the apical series in lateral view falling towards the ventral sides. This peculiar feature observed again this time from two specimens in lateral view has confirmed the archeopyle of B. dorsiprominentis to be of combination type rather than tA or 3I type. It differs from B. alveolae in having only girdle projection in dorsal side and finer ornamentation.