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Impletosphaeridium densum
Impletosphaeridium densum (He Chengquan and Li Peng, 1981, p.65, pl.31, figs.14-17; text-fig.6) He Chengquan and Wang Kede, 1990, p.413.
Holotype: He Chengquan and Li Peng, 1981, pl.31, fig.14; text-fig.6.
Originally Impletosphaeridium polypes subsp. densum, subsequently Kiokansium polypes subsp. densum, thirdly (and now) Impletosphaeridium densum. He Chengquan (1991, p.142) also proposed this combination.
Age: Late Oligocene.
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
1981 lmpletosphaeridium polypes subsp. densum He et Li, He Chengquan, Li Peng, page 65, plate 31, fig to 14-17; Figure6
Description: Body oval, with a large number of fine processes, more than 80 around the body, 7-9μm long, width uniform, solid, the ends expanded or small ball-shaped, like a pin, a few processes ends simple. Wall surface smooth or nearly smooth. Archeopyle unknown. Body length 42-55μm, width 32-33μm.
Discussion: Since Impletosphaeridium polypes (Cookson et Eisenack, 1962) is considered to have a precingular archeopyle, P or 2P type, which has been selected by Davey (1979) as the type species of the genus Bacchidinium; But Impletosphaeridium polypes subsp. densum lacks an archeopyle, so in this book it is promoted from a subspecies to species, still remains in Impletosphaeridium. I. densum is characterized by many processes, pin-shaped, uniform width (base not big) and the ends small ball-like.
Location and stratigraphy: Wuqia County Basebulak; Qimugen fm upper member.
Holotype: He Chengquan and Li Peng, 1981, pl.31, fig.14; text-fig.6.
Originally Impletosphaeridium polypes subsp. densum, subsequently Kiokansium polypes subsp. densum, thirdly (and now) Impletosphaeridium densum. He Chengquan (1991, p.142) also proposed this combination.
Age: Late Oligocene.
Description from He Chengquan, 1991, translated by Suning Hou, 07-01-2019
1981 lmpletosphaeridium polypes subsp. densum He et Li, He Chengquan, Li Peng, page 65, plate 31, fig to 14-17; Figure6
Description: Body oval, with a large number of fine processes, more than 80 around the body, 7-9μm long, width uniform, solid, the ends expanded or small ball-shaped, like a pin, a few processes ends simple. Wall surface smooth or nearly smooth. Archeopyle unknown. Body length 42-55μm, width 32-33μm.
Discussion: Since Impletosphaeridium polypes (Cookson et Eisenack, 1962) is considered to have a precingular archeopyle, P or 2P type, which has been selected by Davey (1979) as the type species of the genus Bacchidinium; But Impletosphaeridium polypes subsp. densum lacks an archeopyle, so in this book it is promoted from a subspecies to species, still remains in Impletosphaeridium. I. densum is characterized by many processes, pin-shaped, uniform width (base not big) and the ends small ball-like.
Location and stratigraphy: Wuqia County Basebulak; Qimugen fm upper member.