Exochosphaeridium bifidum subsp. involutum

"subsp. involutum" (Davey, 1969c, p.29, pl.2, figs.1–3) Lentin and Williams, 1973, p.56.  Emendation: Marheinecke, 1992, p.52, as Exochosphaeridium bifidum subsp. involutum.  Holotype: Davey, 1969c, pl.2, fig.3.  Originally Exochosphaeridium bifidum var. involutum, subsequently Exochosphaeridium bifidum subsp. involutum.  Taxonomic senior synonym: Hystrichosphaeridium (now Exochosphaeridium) majus according to Peyrot (2011, p.284). The possibility of this synonymy was earlier postulated by Marheinecke (1992, p.51).  Age: Campanian–Maastrichtian.

Parent: Exochosphaeridium bifidum