Hystrichosphaeridium recurvatum subsp. parvum
From dinoflaj2
subsp. parvum (Rozen, 1965, p.303-304, pl.4, fig.6; text-fig.13) Lentin and Williams, 1973, p.79. Holotype: Rozen, 1965, pl.4, fig.6; text-fig.13. Originally Hystrichosphaeridium recurvatum var. parvum, subsequently (and now) Hystrichosphaeridium recurvatum subsp. parvum, thirdly Hystrichosphaeridium palmatum subsp. parvum (combination illegitimate), fourthly Hystrichosphaeridium duplum subsp. parvum (combination illegitimate). Age: Late Eocene. Parent: Hystrichosphaeridium recurvatum