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Pyxidinopsis pseudodictyota
Pyxidinopsis pseudodictyota He Chengquan, 1991, p.118-119, pl.7, figs.6-8
Holotype: pl.7, fig.7
Age: Middle Eocene
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
Description: Cyst nearly spherical, the outline round-oval, no apical antapical horn. Cyst wall thickness 1.5-2.5μm, two layers, outer wall thick, the structure is loose or partially laminated, surface with rough embossed ornamentation, the components consist of short ridges and (or) particles (some specimens are mainly short ridges), the length of the ridges varies, can be intertwined with each other into incomplete reticular; Ridge is high, partly extending out of the outline like short blunt spikes. Inner wall thin, no structure. No sulcus or cingulum. The archeopyle was significant, precingular, P-type, the outline horseshoe-shaped, formed by the third precingular plate movement or loss. Operculum preserved in situ or fell off.
Cyst length 65-85μm, width 60-70μm (measured 3); Holotype length 65μm, width 65μm.
Discussion: Current specimens lack the real long processes can not be attributed to Operculodinium. This species is quite similar to Pyxidinopsis composita, but the former is apparently composed of two layers of cyst walls, its surface has sparser, thicker and taller ridges, extending out of the outlines as short spikes. The latter’s outline is small toothed, cyst thick and not stratified, the two are easy to distinguish.
Location and statigraphy: Wuqia county Basebulak and Shache County Quruimu; Wulagen fm.
Holotype: pl.7, fig.7
Age: Middle Eocene
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
Description: Cyst nearly spherical, the outline round-oval, no apical antapical horn. Cyst wall thickness 1.5-2.5μm, two layers, outer wall thick, the structure is loose or partially laminated, surface with rough embossed ornamentation, the components consist of short ridges and (or) particles (some specimens are mainly short ridges), the length of the ridges varies, can be intertwined with each other into incomplete reticular; Ridge is high, partly extending out of the outline like short blunt spikes. Inner wall thin, no structure. No sulcus or cingulum. The archeopyle was significant, precingular, P-type, the outline horseshoe-shaped, formed by the third precingular plate movement or loss. Operculum preserved in situ or fell off.
Cyst length 65-85μm, width 60-70μm (measured 3); Holotype length 65μm, width 65μm.
Discussion: Current specimens lack the real long processes can not be attributed to Operculodinium. This species is quite similar to Pyxidinopsis composita, but the former is apparently composed of two layers of cyst walls, its surface has sparser, thicker and taller ridges, extending out of the outlines as short spikes. The latter’s outline is small toothed, cyst thick and not stratified, the two are easy to distinguish.
Location and statigraphy: Wuqia county Basebulak and Shache County Quruimu; Wulagen fm.