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 (and now) Exochosphaeridium bifidum subsp. involutum.  Marheinecke (1992, p.51) considered that this taxon may be a taxonomic junior synonym of Amphorosphaeridium majus. Age: Campanian-Maastrichtian. Parent: Exochosphaeridium bifidum