Hystrichokolpoma bulbosum (Ehrenberg, 1837b, pl.1, fig.17) Morgenroth, 1968, p.546. Emendation: Morgenroth, 1968, p.546–547, as Hystrichokolpoma bulbosum.

Originally Xanthidium bulbosum (acritarch), subsequently Hystrichosphaera bulbosa (combination not validly published), thirdly Hystrichosphaeridium bulbosum, fourthly Ovum hispidum subsp. bulbosum (combination not validly published, acritarch), fifthly (and now) Hystrichokolpoma bulbosum, sixthly Baltisphaeridium bulbosum (combination not validly published, acritarch).
Lentin and Williams (1977b, p.77) retained this species in Hystrichokolpoma.
Taxonomic senior synonym: Xanthidium (as Hystrichosphaeridium) tubiferum, according to Stover and Evitt (1978, p.55) — however, Lentin and Williams (1981, p.134) retained Hystrichokolpoma bulbosum.
The name Xanthidium bulbosum may not have been validly published in Ehrenberg (1837b) since no description in that publication has been referenced or found.

Holotype: Ehrenberg, 1838, pl.1, fig.17
Neotype: Morgenroth, 1968, pl.44, fig.6, designated by Morgenroth (1968, p.546).
Age: Danian

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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.

Hystrichokolpoma bulbosum (Ehrenberg, 1838) Morgenroth, 1968, emend. Morgenroth, 1968. The large processes on this species have very wide bases, decrease in width rather abruptly at about midheight to form short, narrow distal endings. Narrower processes are closed distally, pointed, but still have expanded bases. Size central body length 31-43 µm, width 30-33 µm, processes length 14-22 µm.
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