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Xenicodinium crassum
Xenicodinium crassum, He Chengquan, 1984; Chen et al., 1988
Originally Stomodinium, subsequently (and now) Xenicodinium
Holotype: He Chengquan, 1984, pl.1, fig.12.
Age: Early-Middle Eocene
Locality and Horizon: Bashibulake, in Wuqia County: Wulagen Formation.
Original description: He Chengquan, 1984 (as Stomodinium crassum):
Description:
Tests subcircular to elliptical in outline; length somewhat greater than width. Upper and lower tests almost equally large. No apical or antapical horns.
Wall quite thick, about 4 to 5 µm; differentiation into layers unclear. Surface has coarse rugae and a few incomplete intertabular sutural features indicated by fine processes. Rugae lack symmetry; most fairly coarse. Bases wide, appearing more or less undulate or bluntly (roundly) dentate on contour line. Rugae on holotype about 0.5 µm high; bases 1 to 1.5 µm wide and able to be interjoined.
Processes spinate, short, solid, stretching obliquely or curved or in inverted state; 1 to 7 µm long. Those appearing on contour line fairly distantly spaced.
Paratabulation very likely gonyaulacacean. Because of surface rugae and incomplete intertabular sutural features, tabulation cannot be determined in detail.
Cingulum displayed to a greater or lesser extent, being indicated by spinate processes in the equatorial region.
No indication of a sulcus observed.
Archaeopyle conspicuously located before the cingulum; precingular, type P (only 3""). Operculum completely detached but generally maintaining original position or adhering to side of archaeopyle.
Dimensions/Size:
Total length (including processes) of 100 to 105 µm: width of 72.5 to 92.5 µm. Tests 87.5 to 97.5 µm long and 72.5 to 100 µm wide (5 measured). Holotype 100 µm in total length and 84 µm in width. Test 93 µm long and 78 µm wide; spines 2 to 7µm long.
Originally Stomodinium, subsequently (and now) Xenicodinium
Holotype: He Chengquan, 1984, pl.1, fig.12.
Age: Early-Middle Eocene
Locality and Horizon: Bashibulake, in Wuqia County: Wulagen Formation.
Original description: He Chengquan, 1984 (as Stomodinium crassum):
Description:
Tests subcircular to elliptical in outline; length somewhat greater than width. Upper and lower tests almost equally large. No apical or antapical horns.
Wall quite thick, about 4 to 5 µm; differentiation into layers unclear. Surface has coarse rugae and a few incomplete intertabular sutural features indicated by fine processes. Rugae lack symmetry; most fairly coarse. Bases wide, appearing more or less undulate or bluntly (roundly) dentate on contour line. Rugae on holotype about 0.5 µm high; bases 1 to 1.5 µm wide and able to be interjoined.
Processes spinate, short, solid, stretching obliquely or curved or in inverted state; 1 to 7 µm long. Those appearing on contour line fairly distantly spaced.
Paratabulation very likely gonyaulacacean. Because of surface rugae and incomplete intertabular sutural features, tabulation cannot be determined in detail.
Cingulum displayed to a greater or lesser extent, being indicated by spinate processes in the equatorial region.
No indication of a sulcus observed.
Archaeopyle conspicuously located before the cingulum; precingular, type P (only 3""). Operculum completely detached but generally maintaining original position or adhering to side of archaeopyle.
Dimensions/Size:
Total length (including processes) of 100 to 105 µm: width of 72.5 to 92.5 µm. Tests 87.5 to 97.5 µm long and 72.5 to 100 µm wide (5 measured). Holotype 100 µm in total length and 84 µm in width. Test 93 µm long and 78 µm wide; spines 2 to 7µm long.