Hystrichosphaeridium tubiferum var. brevispinum Davey and Williams, 1966

Now Hystrichosphaeridium tubiferum ssp. brevispinum. Originally Hystrichosphaeridium tubiferum var. brevispinum, subsequently (and now) Hystrichosphaeridium tubiferum ssp. brevispinum, thirdly Hystrichosphaeridium proprium ssp. brevispinum (name not validly published).
Tax. jr. synonym of Dapsilidinium? fucosum (Valensi, 1955) Lentin and Williams, 1981, according to Below, 1982. Lentin and Williams, 1985, retained Hystrichosphaeridium tubiferum var. brevispinum as a separate taxon.
Lentin and Williams, 1973, elevated this taxon to the subspecies rank as Hystrichosphaeridium tubiferum ssp. brevispinum. Harker and Sarjeant in Harker et al., 1990, retained this taxon as Hystrichosphaeridium tublferum var. brevispinum. Lentin and Williams, 1993, followed Lentin and Williams, 1989, and retain it as Hystrichosphaeridium tubiferum ssp. brevispinum.

Holotype: Davey and Williams, 1966, pl.10, fig.10; Bujak et al., 1980, pl.8, figs.10-12
Age: Early Eocene

Original dignosis: Davey and Williams, 1966, p. 58
A variety of Hystrichsphaeridium tubiferum with processes rarely exceeding one-third of the diameter of the central body.