Hystrichosphaeridium brevispinosum Eisenack, 1931, ex Eisenack, 1938

NOW Pachysphaeridium brevispinosum. Originally Ovum hispidum subsp. brevispinosum (name not validly published), subsequently Hystrichosphaeridium brevispinosum, thirdly Baltisphaeridium brevispinosum, fourthly Buedingiisphaeridium brevispinosum (combination not validly published, Appendix A), fifthly Pachysphaeridium brevispinosum.
This combination was not validly published in Eisenack (1958b, p.400), since that author did not fully reference the basionym.
The name Ovum hispidum subsp. brevispinosum was not validly published in Eisenack (1931) since the specific name Ovum hispidum was not validly published.

Holotype: Eisenack, 1931, pl.5, fig.3 (lost according to Eisenack, 1959)
Neotype: Eisenack, 1959, pl.15, fig.13 (designated by Eisenack 1959)
Age: Silurian