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Pseudoalterbia

From Williams et al., 2017:

[Pseudoalterbia, Mao Shaozhi and Norris, 1988, p. 53

Type species: Pseudoalterbia concinna, Mao Shao-zhi and Norris, 1988 (pl.16, fig.4)]

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Original description: [Mao Shao-zhi and Norris, 1988]:

Diagnosis:
Cyst proximate, pentagonal, with slightly protruding apical and left antapical horns; apical horn usually bluntly pointed, left antapical horn commonly pointed, and right antapical horn greatly reduced or absent. Epitract triangular in ambital view, with two sides convex; hypotract more or less trapezoidal and asymmetrical about the longitudinal axis; the two parts almost equal in size. Autophragm smooth or with scattered, normally isolated features of low relief.
Cingulum well defined by medium-height ridges, planar to slightly helical.
Archeopyle intercalary, type I, standard to attenuate hexa 2a style, transverse AI less than 0.5; operculum detached or attached along its posterior margin.
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