From Williams et al., 2017:

[Cymatiosphaera, O.Wetzel 1933b, p.27 ex Deflandre, 1954, p. 257
Prasinophyte genus.
For a full discussion see Fensome et al. (1990, p.167)

Type species: Cymatiosphaera radiata, Wetzel, 1933b (pl.4, fig.8)]