Hystrichosphaera bulloidea Deflandre and Cookson, 1955, p.264

NOW Spiniferites. Originally Hystrichosphaera, subsequently (and now) Spiniferites.
Taxonomic senior synonym: Xanthidium (as Spiniferites) ramosum, according to Harland (1977b, p.101–102) — however, Lentin and Williams (1981, p.259) retained Hystrichosphaera (as Spiniferites) bulloidea.
Taxonomic junior synonym: Spiniferites nanus, according to Matsuoka (1983a, p.23) — however, Matsuoka (1991, table 2 — p.8) retained Spiniferites nanus.
Motile equivalent: Gonyaulax scrippsiae Kofoid, 1911, according to Wall and Dale (1967, p.352; 1968c, p.270) — however, see Head (1996b, p.1205).

Holotype: Deflandre and Cookson, 1955, pl.5, fig.3-4
Locus typicus: Balcombe Bay, Victoria, Australia
Stratum typicum: Eocene-Miocene

Original diagnosis: Deflandre and Cookson, 1955, p.264
Shell small, spherical or nearly so, having the general appearance of Hystrichosphaera furcata and H. ramosa. Outline circular in well preserved specimens, elliptical or oval when broken. Membrane rather thin and delicate, easily broken and crumpled when, owing to their unnaturally close proximity, the processes seem more numerous than in fully expanded examples. Processes always trifurcate, the 3 branches being widely separated and shortly bifurcate.
Dimensions: Type: overall diameter 59 µm, shell 36 µm. Range: overall diameter 54-64 µm, shell 30-37 µm, processes 10-15 µm.