Baltisphaeridium piriferum Appendix A

"piriferum" (Eisenack, 1954a, p.206–207, pl.1, figs.1a–b; text-fig.1) Downie and Sarjeant, 1965, p.94.  Holotype: Eisenack, 1954a, pl.1, figs.1a–b.  NOW Visbysphaera (Appendix A).  Originally Hystrichosphaeridium, subsequently Baltisphaeridium, thirdly Multiplicisphaeridium (Appendix A), fourthly (and now) Visbysphaera (Appendix A).  Taxonomic junior synonyms: Baltisphaeridium hermosum Cramer and Diez, 1968 (name not validly published), an acritarch species, according to Cramer (1970, p.148); Baltisphaeridium (now Visbysphaera) dilatispinosum Downie, 1963, an acritarch species, according to Eisenack (1965c, p.263) — however, Fensome et al. (1990, p.530) retained Baltisphaeridium (now Visbysphaera) dilatispinosum.  This combination was not validly published in Downie and Sarjeant (1963, p.90), since these authors did not fully reference the basionym.  Age: Silurian (late Llandovery).

Parent: Baltisphaeridium_Appendix A