Alterbia ovalis, He Chengquan, 1991

Following I.C.N. Article 55.1, the species name Alterbia ovalis is validly published even though the generic name Alterbia is illegitimate.

Holotype: He Chengquan, 1991, pl.29, fig.7
Location and stratigraphy: Wuqia County, Basebulak region; upper Kukebai Fm -bottom Wuyitake Fm.
Age: Turonian-Middle Eocene

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

Description:
Outer wall contour oval or circular pentagonal with smooth and pronounced convexities on both sides of the waist, length nearly equals to width or slightly larger, etc., or length larger than wide.
Epicyst and hypocyst are nearly equal. Epicyst triangular, sides convex, apical horn tiny or almost lacking, and occasionally the top with a hole; Hypocyst inverted trapezoid, the sides are of nearly flat or slightly convex, two antapical horns are degradated, or only one of the those slightly protrudes out of the outlines, blunt end.
Cingulum equatorial position, shallow flat, annular, width 6-7 μm, the edge is marked by the granular ridge. Sulcus fuzzy.
The outer wall surface is finely granular. Inner body contour nearly circular, thin wall, there is no obvious ornamentation on the surface; It is separated from the outer wall widely.
The archeopyle is small, obvious, intercalary, shown by the main crack of the archeopyle. Operculum preserved in situ.

Dimensions:
Cyst length 50-60 μm, width 45-52.5 μm, inner body length 32-43 μm, width 36-45 μm (4 speciemens measured);
Holotype length 52.53 μm, width 52.5 μm, inner body length 43 μm, width 45 μm cingulum, width 7.5 μm