Baltisphaeridium rjabininii, (Timofeev, 1959), Downie and Sarjeant, 1965

Originally Hystrichosphaeridium, subsequently (and now) Baltisphaeridium. This
combination was not validly published in Downie and Sarjeant, 1963 since these authors did not fully reference the basionym.

Holotype: Timofeev, 1959, pl.4, fig.24
Age: Early Ordovician