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Conosphaeridium truncatum

Conosphaeridium truncatum, He Chengquan, 1991

Holotype: He Chengquan, 1991, pl.14, fig.12
Location and stratigraphy: Wuqia county Basebulak; Wulagen fm.
Age: Middle Eocene

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Original description: [He Chengquan, 1991]: (translated by Suning Hou, 07-01-2019):

Description:
Ellipse body, grows length larger than width. Wall thickness about 2 μm, surface with weak particles - short wrinkles, or rough.
There are more than 20 strong short processes, truncated top conical-pyramide-frustum, solid, almost every process has about 3-6 longitudinal coarse ribs and the alternating grooves, the ribs and grooves extend from the base to the distal end, occasionally the ribs of the adjacent processes base are connected to each other; Except the apical and antapical processes are longer (12 μm), the length of other processes does not vary significantly usually 3-7.5 μm long , 7-10 μm wide. Processes are intratabular, each representing a plate, the tabulation is 3'(?), 6’’ 6c, 5'", 1’’’’. There is a bridge ridge at the hypocyst, it may represent the sulcus area.
Archeopyle precingular, P-type, formed by the movement of the third precingular plate.

Dimensions:
Body length 100 μm, width 77.5 μm.

Affinities:
The new species is similar to the type species of the genus in the structure of the processes. However, the former’s length is larger than width, processes ends truncated.
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