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Diconodinium sinense
Diconodinium sinense He Chengquan, 1991
Holotype: He Chengquan, 1991, pl.2, fig.3
Age: Cenomanian-Paleocene
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
Description: Cyst ventral-dorsal flattened, contoured biconvex - rhombus, laterally symmetrical. The waist is convex outwards. The shape of the upper and lower cysts is similar, but the upper cyst is larger. There is an apical antapical horn, the ends are relatively blunt, sometimes the antapical horn is narrower than the apical horn, length 5-8μm, apical horn length 7.5-10μm . Cingulum deviated to the lower cyst, obvious or fuzzy, width 5 μm, the edge is marked by fine ridges or equatorial transversal wrinkles. Sulcus absent. No inner body. Cyst wal single laye, thin, smooth surface. Archeopyle intercalary, the outline is nearly trapezoidal or hexagonal, formed by the loss or movement of the second intercalary plate 2a. Operculum off or in situ preserved. Cyst length 62.5-75μm, width 45-55μm (measured 5); Holotype length 62.5μm, width 46.5μm., Discussion: This species differs from Diconodinium paucigranulatum in the smooth wall surface; It dffers from other species in the genus in the laterally symmetrical cyst and the smooth surface. As fas as is known, the specimens classified in this genus mostly have short spikes in the surface and their archeopyle is hard to recognize.
Location and stratigraphy: Wuqia County Basebulak, Qimugen fm lower member; Urukqiati, Kukebai fm lower midlle members and the lower member of Qimugen fm.
Holotype: He Chengquan, 1991, pl.2, fig.3
Age: Cenomanian-Paleocene
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
Description: Cyst ventral-dorsal flattened, contoured biconvex - rhombus, laterally symmetrical. The waist is convex outwards. The shape of the upper and lower cysts is similar, but the upper cyst is larger. There is an apical antapical horn, the ends are relatively blunt, sometimes the antapical horn is narrower than the apical horn, length 5-8μm, apical horn length 7.5-10μm . Cingulum deviated to the lower cyst, obvious or fuzzy, width 5 μm, the edge is marked by fine ridges or equatorial transversal wrinkles. Sulcus absent. No inner body. Cyst wal single laye, thin, smooth surface. Archeopyle intercalary, the outline is nearly trapezoidal or hexagonal, formed by the loss or movement of the second intercalary plate 2a. Operculum off or in situ preserved. Cyst length 62.5-75μm, width 45-55μm (measured 5); Holotype length 62.5μm, width 46.5μm., Discussion: This species differs from Diconodinium paucigranulatum in the smooth wall surface; It dffers from other species in the genus in the laterally symmetrical cyst and the smooth surface. As fas as is known, the specimens classified in this genus mostly have short spikes in the surface and their archeopyle is hard to recognize.
Location and stratigraphy: Wuqia County Basebulak, Qimugen fm lower member; Urukqiati, Kukebai fm lower midlle members and the lower member of Qimugen fm.