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Alterbia bellula
Alterbia bellula, He Chengquan, 1991
Following I.C.N. Article 55.1, the species name Alterbia bellula is validly published even though the generic name Alterbia is illegitimate. This name was a not validly published in Xu Jinli (1987, p.150), who cited it as "Alterbia bellula He (MS)" — as a provisional manuscript name.
Holotype: He Chengquan, 1991, pl.29, fig.12.
Location and stratigraphy: Xinjiang province Wuqia county Wulukeqiati, wuyitake formation; Shandong province Guangyao county shahejie formation upper member 4
Age: middle Eocene.
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Original description: [He Chengquan, 1991]: (translated by Suning Hou, 07-01-2019):
Description:
The cyst is dorsal-ventral flattened and contours pentagonal, with straight edges, length slightly larger than width. It is divided into 2 nearly equal parts or slightly different parts by the cingulum: The epicyst is triangle, has a conical small apical horn, the top is blunt; the hypocyst is slightly larger, inverted trapezoid, and the two antapical horns are quite degenerated, only one is slightly displayed. Cingulum is slightly deviated to the upper cyst, shallow flat, annular, width 8 μm, the edge is marked by fine granular ridges. The sulcus is unknown. The outer wall surface is finely grained. The inner body contour is oval, thin wall, can be wrinkled, no significant ornamentation on the surface; It is widely separated from the outer wall.
Archeopyle obvious, intercalary. The operculum falls off.
Dimensions:
Cyst length 62 μm, width 51 μm, the inner body length 45 μm, 37 μm.
Affinities/Comparison:
This new species is different from Alterbia ambigua with no noticeable elongation of the cyst; it differs from A. ovalis in a clearly defined pentagon outline (straight side).
Following I.C.N. Article 55.1, the species name Alterbia bellula is validly published even though the generic name Alterbia is illegitimate. This name was a not validly published in Xu Jinli (1987, p.150), who cited it as "Alterbia bellula He (MS)" — as a provisional manuscript name.
Holotype: He Chengquan, 1991, pl.29, fig.12.
Location and stratigraphy: Xinjiang province Wuqia county Wulukeqiati, wuyitake formation; Shandong province Guangyao county shahejie formation upper member 4
Age: middle Eocene.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [He Chengquan, 1991]: (translated by Suning Hou, 07-01-2019):
Description:
The cyst is dorsal-ventral flattened and contours pentagonal, with straight edges, length slightly larger than width. It is divided into 2 nearly equal parts or slightly different parts by the cingulum: The epicyst is triangle, has a conical small apical horn, the top is blunt; the hypocyst is slightly larger, inverted trapezoid, and the two antapical horns are quite degenerated, only one is slightly displayed. Cingulum is slightly deviated to the upper cyst, shallow flat, annular, width 8 μm, the edge is marked by fine granular ridges. The sulcus is unknown. The outer wall surface is finely grained. The inner body contour is oval, thin wall, can be wrinkled, no significant ornamentation on the surface; It is widely separated from the outer wall.
Archeopyle obvious, intercalary. The operculum falls off.
Dimensions:
Cyst length 62 μm, width 51 μm, the inner body length 45 μm, 37 μm.
Affinities/Comparison:
This new species is different from Alterbia ambigua with no noticeable elongation of the cyst; it differs from A. ovalis in a clearly defined pentagon outline (straight side).