Geiselodinium minor (Yu Jingxian et al., 1981) Chen et al., 1988; Emendation: Mao Shaozhi et al., 1995, p.50, as Sanshuia minor.

Now Saeptodinium. Originally Sanshula, subsequently Geiselodinium, thirdly (and now) Saeptodinium.
Holotype: Yu Jingxian et al., 1981, pl.1, fig.13
Age: Late Cretaceous

Sanshuia minor gen. et sp. nov.
Description: Cysts small, with a tripodal outline. Periphragm about 1.0 µm thick. Endocyst indistinct. Only at apical and antapical horns can separation from endocyst be observed. Surface rough, with irregular creases. Upper test triangular, 18.4 µm high. Apical horn is a pointed extension of upper test. Apical pore circular. Lower test trapezoidal, 18 µm high. Two antapical horns of unequal development; larger ones about 4.6 µm long and smaller ones 2.3 µm. No indication of tabulation. No archaeopyle. Cingulum annular, decorated on edge with rough, undulate ridge. A few "nuclei" near ventral section.
Size: Cysts 25.3 - 36.8 µm long and 27.6 - 30 µm wide. Holotype 36.8 x 27.6 µm.

Discussion: This species is distinguished from S. minuta (Jiabo) by its small individuals, tripodal outline and narrow cingulum decorated on the edge with a rough ridge.