Hystrichosphaera longispinosa (Eisenack, 1931, p.110–111, pl.5, figs.6–17) Wetzel, 1932, caption to pl.3, fig.12 — p.144.

Now Baltisphaeridium longispinosum. Originally Hystrichosphaera longzspinosa, subsequently Hystrichosphaeridium longispinosum, thirdly (and now) Baltisphaeridium longispinosum; see also Ouum hispidum ssp. Iongispinosum (name not validly published) and Micrhystridium longispinosum (combination not validly published).
The name Hystrichosphaera longispinosa was not validly published in O. Wetzel, 1932, caption to pl.3, fig.12) since the generic name Hystrichosphaera was not validly published until 1933.

Holotype: Eisenack, 1931, pl.5, fig.10 (as Ovum hispidum ssp. Iongispinosum, lost according to Eisenack, 1959)
Neotype: Eisenack, 1959, pl.15, fig.1 (designated by Eisenack (1959)
Age: Ordovician (based on material from an erratic)