Apteodinium granorugosum, He Chengquan, 1991

Holotype: He Chengquan, 1991, pl.5, fig.34.
Location and stratigraphy: Wuqia County Basebulak; Wulagen fm and Basebulak fm member two and three.
Age: Middle-Late Eocene

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Original description: [He Chengquan, 1991]: (translated by Suning Hou, 07-01-2019):

Description:
The cyst is nearly spherical, ventral-dorsal or lateral outline is round rhombus, length and width are nearly equal or width larger than length, no apical antapical horns. Divided into 2 nearly equal parts by the cingulum, the shape of the upper and lower cysts are almost the same, semi-circular. Cingulum shallow concave, spiral, width 6.5 a 7μm, the edge is marked by the ridge, the ridge is fine or high, extending out of the outline 1.8μm like a spine; The ends of the cingulum stagger about twice the width of the cingulum on the ventral surface. The sulcus is fuzzy, generally limited to the lower cyst. Cyst wall is thin, non-stratified, surface granular-short wrinkles, rough.
The archeopyle is large, precingular, P-type, formed by the movement of the third precingular plate.
The operculum is preserved in situ or adhered to the edge of the archeopyle.

Dimensions:
Cyst length 61-72μm, width 72.5- 75μm (measured 3); Holotype length 72μm, width 72.5μm, cingulum width 7 μm.