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Apteodinium rhombiforme
Apteodinium rhombiforme, He Chengquan, 1991
This species was not validly published in He Chengquan and Wang Kede, 1990, who gave the citation "Apteodinium rhombiforme He".
Holotype: He Chengquan, 1991, pl.3, fig.1
Location and stratigraphy: Wuqia County Basebulak; Qimugen fm lower member and Basebulak fm member two and three.
Age: Paleocene-Eocene
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Original description: [He Chengquan, 1991]: (translated by Suning Hou, 07-01-2019):
Description:
Cyst rhombus, generally length and width are nearly equal or length larger than the width, upper and lower cyst are equal and almost symmetrical. The epicyst is a little conical, the top is round convex, the apical horn is micro-displayed or papillary; Hypocyst high-semicircular, lack of antapical horn.
Cingulum equatorial position, annular, edge marked by two lateral equatorial wrinkles or fine ridges. Sulcus unknown.
The wall is about 1μm thick, the surface with fine particles, some of the particles can be connected into a short wrinkle, the contour line is nearly smooth.
Archeopyle precingular, the outline of the horseshoe shape, formed by the movement of the third precingular plate.
Cover preserved in situ.
Dimensions:
Cyst length 57-77μm, width 57.5-65μm, cingulum width 5-5.5μm (measured 2);
Holotype length 77μm, width 65μm, cingulum width 5μm.
Affinities:
The new species is similar in appearance to Apteodinium cingulatum, but the former’s apical horn is not well developed, almost not isolated, and a transverse wrinkle-shaped cingulum.
This species was not validly published in He Chengquan and Wang Kede, 1990, who gave the citation "Apteodinium rhombiforme He".
Holotype: He Chengquan, 1991, pl.3, fig.1
Location and stratigraphy: Wuqia County Basebulak; Qimugen fm lower member and Basebulak fm member two and three.
Age: Paleocene-Eocene
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [He Chengquan, 1991]: (translated by Suning Hou, 07-01-2019):
Description:
Cyst rhombus, generally length and width are nearly equal or length larger than the width, upper and lower cyst are equal and almost symmetrical. The epicyst is a little conical, the top is round convex, the apical horn is micro-displayed or papillary; Hypocyst high-semicircular, lack of antapical horn.
Cingulum equatorial position, annular, edge marked by two lateral equatorial wrinkles or fine ridges. Sulcus unknown.
The wall is about 1μm thick, the surface with fine particles, some of the particles can be connected into a short wrinkle, the contour line is nearly smooth.
Archeopyle precingular, the outline of the horseshoe shape, formed by the movement of the third precingular plate.
Cover preserved in situ.
Dimensions:
Cyst length 57-77μm, width 57.5-65μm, cingulum width 5-5.5μm (measured 2);
Holotype length 77μm, width 65μm, cingulum width 5μm.
Affinities:
The new species is similar in appearance to Apteodinium cingulatum, but the former’s apical horn is not well developed, almost not isolated, and a transverse wrinkle-shaped cingulum.