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Pyxidinopsis composita
Pyxidinopsis composita He Chengquan, 1991
Holotype: He Chengquan, 1991, pl.7, fig.1
Age: Middle Eocene
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
Description Cyst is nearly spherical, outline oval - round, no apical antapical horns. Lack of sulcus and cingulum. Wall thickness 4μm, stratification unclear; Outer wall surface with complex fine relief-like ornamentation, more or less forming coarse incomplete fine reticulate; Carves formed by dense ridges (wrinkles) and particles, the components of the carves can vary on different specimens, sometimes mainly particles, sometimes mainly short ridges and the thickness length of these components can also change, the cyst outline is small dentate.The archeopyle is significant, precingular, P-type, the outline horseshoe shape, formed by the third precingular plate movement or loss. Operculum is usually preserved in situ. Cyst length 72.5- 85μm, width 60-75μm (measured 5); Holotype length 72.5μm, width 60μm.
Discussion: This new species is characterized by the complex fine low relief ornamentation on the surface. The decoration appears to be quite consistent with that of Batiacasphaera, but current specimens can not be classified as Batiacasphaera because its archeopyle is precingular rather than apical , archeopyle or operculum are apparently horseshoe-shaped instead of hexa-heptagonal
Location and stratigraphy: Wuqia County Basebulak; Wulagen fm.
Holotype: He Chengquan, 1991, pl.7, fig.1
Age: Middle Eocene
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
Description Cyst is nearly spherical, outline oval - round, no apical antapical horns. Lack of sulcus and cingulum. Wall thickness 4μm, stratification unclear; Outer wall surface with complex fine relief-like ornamentation, more or less forming coarse incomplete fine reticulate; Carves formed by dense ridges (wrinkles) and particles, the components of the carves can vary on different specimens, sometimes mainly particles, sometimes mainly short ridges and the thickness length of these components can also change, the cyst outline is small dentate.The archeopyle is significant, precingular, P-type, the outline horseshoe shape, formed by the third precingular plate movement or loss. Operculum is usually preserved in situ. Cyst length 72.5- 85μm, width 60-75μm (measured 5); Holotype length 72.5μm, width 60μm.
Discussion: This new species is characterized by the complex fine low relief ornamentation on the surface. The decoration appears to be quite consistent with that of Batiacasphaera, but current specimens can not be classified as Batiacasphaera because its archeopyle is precingular rather than apical , archeopyle or operculum are apparently horseshoe-shaped instead of hexa-heptagonal
Location and stratigraphy: Wuqia County Basebulak; Wulagen fm.