Veryhachium geometricum (Deflandre, 1945) Stockmans and Williere, 1963

Originally Hystrichosphaeridium geometricum, subsequently (and now)
Veryhachium geometricum; see also Veryhachium trispinosum ssp. geometricum (an acritarch subspecies; combination not validly published). This combination was not validly published in Deunff, 1954 since that author neither fully referenced the
basionym nor clearly used the name Veryhachium geometricum.
Holotype: Deflandre, 1945, pl.2, fig.2
Age: Middle Silurian