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Sinocysta minuta
Sinocysta minuta He Chengquan, 1984
Now Laciniadinium. Originally Sinocysta, subsequently (and now) Laciniadinium.
Holotype: He Chengquan, 1984, pl.1, fig.5; text-fig.1
Age: Late Cretaceous
Description: Tests fairly small, with ventro-dorsal flattening; outline roundly polygonal; length and width nearly equal; girdle region bulges conspicuously outward. Upper test triangular and slightly larger than lower test. Apical convexity faintly displayed; apical pore present. Lower test has appearance of inverted ladder; two antapical horns lacking. Cingulum shallow, located at broadest part of test but tending somewhat towards lower test; annular; about 5 µm wide; edges decorated with fine ridges. Sulcus much wider than cingulum and located on ventral surface of lower test. Test wall thin and single-layered; surface has short longitudinal striae. Archaeopyle located on dorsal surface below apical section; combination; type tI3Pa; no apical plates contained during its formation. Size: Tests 37.5 to 45 µm long and 38.5 to 40 µm wide (3 specimens measured). Holotype 42.5 µm long and 40 µm wide; cingulum about 5 µm wide and sulcus about 12 µm wide.
Note: This species is characterized by small tests and absence of antapical horns.
Locality and Horizon: Moguigou, in Bashibulake, Wuqia County: Wuyitake Formation; Bashibulake: lower section of the Qimugen Formation.
Now Laciniadinium. Originally Sinocysta, subsequently (and now) Laciniadinium.
Holotype: He Chengquan, 1984, pl.1, fig.5; text-fig.1
Age: Late Cretaceous
Description: Tests fairly small, with ventro-dorsal flattening; outline roundly polygonal; length and width nearly equal; girdle region bulges conspicuously outward. Upper test triangular and slightly larger than lower test. Apical convexity faintly displayed; apical pore present. Lower test has appearance of inverted ladder; two antapical horns lacking. Cingulum shallow, located at broadest part of test but tending somewhat towards lower test; annular; about 5 µm wide; edges decorated with fine ridges. Sulcus much wider than cingulum and located on ventral surface of lower test. Test wall thin and single-layered; surface has short longitudinal striae. Archaeopyle located on dorsal surface below apical section; combination; type tI3Pa; no apical plates contained during its formation. Size: Tests 37.5 to 45 µm long and 38.5 to 40 µm wide (3 specimens measured). Holotype 42.5 µm long and 40 µm wide; cingulum about 5 µm wide and sulcus about 12 µm wide.
Note: This species is characterized by small tests and absence of antapical horns.
Locality and Horizon: Moguigou, in Bashibulake, Wuqia County: Wuyitake Formation; Bashibulake: lower section of the Qimugen Formation.