Hystrichosphaeridium tuberatum Downie, 1958

Now Goniosphaeridium. Originally Hystrichosphaeridium, subsequently Baltisphaeridium, thirdly Acanthodiacrodium, fourthly Vulcanisphaera, fifthly (and now) Goniosphaeridium.

Holotype: Downie, 1958, pl.17, fig.3
Age: Early Ordovician