Baltisphaeridium polygonale, (Eisenack, 1931 ex Eisenack, 1938), Eisenack, 1959

Now Goniosphaeridium polygonale (an acritarch species). Originally Hystrichosphaeridium polygonale, subsequently Baltisphaeridium polygonale, thirdly (and now) Goniosphaeridium polygonale (an acritarch species); see also Ovum hispidum ssp. polygonale (combination not validly published), Veryhachium polygonale (an acritarch species; combination not validly published) and Polygonium polygonale (an acritarch species; combination not validly published). Tax. sr. synonym of Impletosphaeridium? primordiale W.Wetzel, 1967, according to Eisenack et al., 1973. Tax. sr. synonym of the acritarch species Veryhachium (al. Goniosphaeridium) splendens Paris and Deunff, 1970, according to Turner, 1984 who believed Goniosphaeridium splendens to be the senior name.
Tax. sr. synonym of the acritarch species Hystrichosphaeridium (al. Baltisphaeridium) sexradiatum Timofeev, 1959, according to Eisenack, 1965.

Holotype: Eisenack, 1931, pl.4, fig.19; lost, according to Eisenack, 1959
Neotype: Paris and Deunff, 1970, pl.1, fig.4 (as Veryhachium splendens), designated by Fensome et al., 1990 (see discussion under Goniosphaeridium polygonale; an acritarch species)
Age: Silurian (based on material from an erratic)