Pseudoalterbia concinna Mao Shaozhi and Norris, 1988

Holotype: Mao Shaozhi and Norris, 1988, pl.16, fig.4; Fensome et al., 1993, p.1067, fig.1
Paratype: Mao Shaozhi and Norris, 1988; Fensome et al., 1993
Locus typicus: Wuluokeqiate section, Tarim Basin, Xinjiong Province, China
Stratum typicum: Turonian-Santonian

Original diagnosis: Mao Shaozhi and Norris, 1988, p.53
A species of Pseudoalterbia having a pentagonal or subrhomboidal cyst with an apical horn and a left antapical horn.

Original description: Mao Shaozhi and Norris, 1988, p.53
Cyst proximate, pentagonal in ambital view. Epitract having a triangular ambitus, with a short rounded apical horn and slightly convex sides. Hypotract approximally triangular or irregularly trapezoidal in ambital view with only a pointed left antapical horn; right antapical horn never developed. Structures posterior to apical horn similar to the subapical thickening and quasi-tabular ridges observed by Norris and Hedlund (1972: 50-52) in their Palaeoperidinium from the Albian of Oklahoma. Autophragm thin, smooth or finely granulate; commonly folded, most folds being short and parallel to the long axis of the cyst. Cingulum clearly defined by ridges; planar or slightly helical and dividing the cyst into two almost equal parts. Archeopyle intercalary, type (I), hexa style, AI 0.37 to 0.47 (holotype 0.44); operculum detached or attached posteriorly.
Size: Holotype: length 62 µm, width 45 µm. Range of 13 specimens: length 56-83 µm, width 36-63 µm.