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Impletosphaeridium polypes ssp. densum
Impletosphaeridium polypes ssp. densum He Chengquan and Li Peng, 1981
Now Impletosphaeridium densum. Originally Impletosphaeridium polypes ssp. densum, subsequently Kiokansium polypes ssp. densum, thirdly (and now) Impletosphaeridium densum.
Holotype: He Chengquan and Li Peng, 1981, pl.31, fig.14, text-fig.6
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.
Now Impletosphaeridium densum. Originally Impletosphaeridium polypes ssp. densum, subsequently Kiokansium polypes ssp. densum, thirdly (and now) Impletosphaeridium densum.
Holotype: He Chengquan and Li Peng, 1981, pl.31, fig.14, text-fig.6
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.