Palaeohystrichosphaeridium williereae (Martin, 1966) Eiserhardt, 1986

NOW Dilatisphaera (Acritarch). Originally Hystrichosphaeridium, subsequently Dilatisphaera (combination not validly published, Acritarch), thirdly Palaeohystrichosphaeridium, fourthly (and now) Dilatisphaera.
Taxonomic junior synonym: Ozotobrachion? podolicus Sheshegova, 1973, an acritarch species, according to Kiryanov (1978, p.90).

Holotype: Martin, 1966, pl.1, fig.23
Age: Silurian (Llandovery)