From Fensome et al., 2019:
Tenua biornata ssp. crassa Jiabo, 1978, p.52, pl.23, figs.1–4.
Holotype: Jiabo, 1978, pl.23, fig.3. Originally Tenua biornata subsp. crassa, subsequently Kallosphaeridium biornatum subsp. crassum (combination not validly published), thirdly Kallosphaeridium biparatum subsp. crassum, fourthly Batiacasphaera biornata subsp. crassa, fifthy Sentusidinium biornatum subsp. crassum.
Taxonomic senior synonym: Sentusidinium bifidum, according to Wood et al. (2016, p.83).
Age: early Tertiary.

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