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Bellatudinium fusum

Bellatudinium fusum, Yu Jingxianet al., 1981

NOW Laciniadinium. Originally Bellatudinium, subsequently (and now) Laciniadinium.

Holotype: Yu Jingxian et al., 1981, pl.1, fig.27
Age: Late Cretaceous

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Original description: [Yu Jingxianet al., 1981]:

Description:
Outline prismatic to pentagonal. Periphragm only, thin. Along edge of body is fine, irregular sutural ridge or low, flat and narrow ridge.
Surface granulate or with fine, tangled ridges. Upper test triangular, larger than lower test.
Apical horn conspicuous, tubular or acicular, 2.3 - 7 µm high, closed at end. Lower test irregularly trapezoidal. Two antapical horns of equal or unequal size, long ones being 4 - 6 µm and short ones 2.3 - 4 µm.
Cingulum annular, 3 - 4.6 µm wide, with edge limited by fine undular ridge projecting beyond the line of contour.
Sulcus triangular; apex reaches upper test. "Nuclei" frequently appear in ventral section where cingulum and sulcus meet and are surrounded by radiating sutural ridges, giving appearance of "flowers".

Dimensions/Size:
Cysts 39 - 43.7 µm long and 29.6 - 34.5 µm wide. Holotype 48.3 x 29.6 µm.

Affinities/Discussion:
This species is distinguished from B. conspicuum by its small individuals, prismatic to pentagonal outline, larger upper test, conspicuously tabular or acicular apical horns, and radiating striae on periphery of "nuclei" that create the effect of "flowers".
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