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Apteodinium cingulatum
Apteodinium cingulatum, He Chengquan, 1991
Holotype: He Chengquan, 1991, pl.3, fig.19.
Location and stratigraphy: Wuqia County Basebulak; Kukebai fm, middle member.
Age: Cennmanian
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Original description: [He Chengquan, 1991]: (translated by Suning Hou, 07-01-2019):
Description:
Cyst lateral outline oval-rhombus, length larger than width or nearly equal to each other. Upper and lower cysts are nearly equal. Upper cyst is a little conical, slightly convex on the sides, with a short apical horn, papillary, length 5-5.5μm. Lower cyst high semicircle , lack of antapical horns. The cingulum is at the equator position, obvious, shallow flat, nearly annular-spiral, width 5-7μm. Its edge is decorated with fine ridges; In addition to the holotype, the ridge extends outwards 2.5μm like a spike on the sides; Due to the lateral folding, both ends of the cingulum are on one side, the staggered width is difficult to measure. There is a vertical blade-shaped wrinkle on the near side of the cyst, it may be equivalent to the location of the sulcus. Cyst wall thickness around 1μm, generally stratified unclear, the surface is nearly smooth or rough particles - short wrinkles. The archeopyle is large, precingular style, formed by the movement of the third precingular plate. The operculum is usually attached to the edge of the archeoplye or preserved in situ.
Dimensions:
Cyst length 67-80μm, width 55-67μm (measured 4); the holotype length 67μm, width 55μm, apical horn length 5μm, cingulum width 5μm.
Affinities/Comparison:
The new species is distinguished from Apteodinium maculatum, A. conjunctum in that the cyst is longer, the apical horn is cylindrical, the cingulums are well defined, and the marginal ridges are usually higher (short spines at the side of the cyst). Similar specimens (Below, 1984, pl. I, fig. I I) were found in the Apricus-Seneman period in Northwest Africa.
Holotype: He Chengquan, 1991, pl.3, fig.19.
Location and stratigraphy: Wuqia County Basebulak; Kukebai fm, middle member.
Age: Cennmanian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [He Chengquan, 1991]: (translated by Suning Hou, 07-01-2019):
Description:
Cyst lateral outline oval-rhombus, length larger than width or nearly equal to each other. Upper and lower cysts are nearly equal. Upper cyst is a little conical, slightly convex on the sides, with a short apical horn, papillary, length 5-5.5μm. Lower cyst high semicircle , lack of antapical horns. The cingulum is at the equator position, obvious, shallow flat, nearly annular-spiral, width 5-7μm. Its edge is decorated with fine ridges; In addition to the holotype, the ridge extends outwards 2.5μm like a spike on the sides; Due to the lateral folding, both ends of the cingulum are on one side, the staggered width is difficult to measure. There is a vertical blade-shaped wrinkle on the near side of the cyst, it may be equivalent to the location of the sulcus. Cyst wall thickness around 1μm, generally stratified unclear, the surface is nearly smooth or rough particles - short wrinkles. The archeopyle is large, precingular style, formed by the movement of the third precingular plate. The operculum is usually attached to the edge of the archeoplye or preserved in situ.
Dimensions:
Cyst length 67-80μm, width 55-67μm (measured 4); the holotype length 67μm, width 55μm, apical horn length 5μm, cingulum width 5μm.
Affinities/Comparison:
The new species is distinguished from Apteodinium maculatum, A. conjunctum in that the cyst is longer, the apical horn is cylindrical, the cingulums are well defined, and the marginal ridges are usually higher (short spines at the side of the cyst). Similar specimens (Below, 1984, pl. I, fig. I I) were found in the Apricus-Seneman period in Northwest Africa.