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Trichodinium castanea ssp. bifurcatum

From Fensome et al., 2019:
Trichodinium castanea ssp. bifurcatum (Jain and Millepied, 1975, p.140, pl.1, figs.14–16) Schrank, 1987, p.263.
Holotype: Jain and Millepied, 1975, pl.1, fig.14; Jan du Chêne et al., 1986a, pl.121, figs.6–8.
Originally Trichodinium bifurcatum, subsequently (and now) Trichodinium castanea subsp. bifurcatum.
Age: Maastrichtian.

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Original description: [Jain and Millepied, 1975]:

Trichodinium bifurcatum sp. nov. (Pl. 1, Fig. 14-16)
Holotype - Pl. 1, Fig. 14; Slide No. 8668-7.
Type locality Bore hole no. CM-4, depth 980 metres; Senegal Basin, W. Africa.
Horizon - Maestrichtian.
Diagnosis - Shell oval to spherical, girdle narrow; apical horn madc up of three large spines with a short central rounded hump in between; longitudinal furrow present, mostly restricted to hypotheca ; shel mcmbrane spongeous, punctate, sparcely covered with short spines; spine base broader, tips blunt or bifid, both types occur together. Archaeopyle precingular, formed of one complete plate extending from apex to cingulum. Tabulation indeterminable.

Measurements
Overall shell size: holotype: 65.5 x 65.5 μm, range: 60-70 μm
girdle width: holotype: 5 μm, range: 5-7 μm
apical horn: holotype: 4 x 4 μm, range: 4-6 x 4-6 μm
spine size: holotype: 4 x 2.6 μm, range: 2-6 x 1-3 μm

Comparison - Trichodinium bifurcalum sp. nov. resembles best with T. paucispinum Eisenack & Cookson (1960) in having apical horn formed by three divergent spines, sparscly placed spines with broader base; but differs in its much smaller size, bifurcated spine types, shorter apical horn with hump like rounded projection in between three divergent spines.
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