Hystrichosphaeridium plicatum
From dinoflaj3
"plicatum" Maier, 1959, p.318, pl.33, fig.1. Holotype: Maier, 1959, pl.33, fig.1. Originally Hystrichosphaeridium, subsequently (and now) Baltisphaeridium (Appendix A). Taxonomic senior synonym (at subspecific rank): Hystrichosphaera (as Spiniferites) ramosa subsp. gracilis, according to Sarjeant (1983, p.93). Age: middle Oligocene.
Parent: Hystrichosphaeridium