Hystrichosphaeridium aculeatum

"aculeatum" Timofeev, 1959, p.54, pl.4, fig.21. Holotype: Timofeev, 1959, pl.4, fig.21. NOW Baltisphaeridium (Appendix A). Originally Hystrichosphaeridium, subsequently (and now) Baltisphaeridium (Appendix A). Age: Early Ordovician.