Bion bacifer, Eisenack, 1934

Now Bacisphaeridium (an acritarch genus). Originally Bion, subsequently Hystrichosphaeridium, thirdly (and now) Bacisphaeridium (an acritarch genus); see also Baltisphaeridium (an acritarch genus; combination not validly published) and Veryhachium (an acritarch genus; combination not validly published).

Holotype: Eisenack, 1934, pl.4, fig.20; lost according to Eisenack, 1962
Neotype: Eisenack, 1962, pl.44, fig.3; designated by Eisenack, 1962
Age: Late Ordovician