Hystrichosphaeridium ancoriferum Cookson and Eisenack, 1960; Emendation: Cookson and Eisenack, 1968, p.119-120, as Cleistosphaeridium ancoriferum.

NOW Sepispinula. Originally Hystrichosphaeridium, subsequently Cleistosphaeridium, thirdly (and now) Sepispinula.
Taxonomic senior synonym: Micrhystridium (as Polysphaeridium, now Sepispinula?) ambiguum, according to Yun Hyesu (1981, p.44) and Schiøler and Wilson (1998, p328) - however, Masure in Fauconnier and Masure (2004, p.499) retained Sepispinula ancorifera. Taxonomic senior synonym: Hystrichosphaeridium (now Sepispinula?) huguoniotii, according to Clarke and Verdier (1967, p.54) - however, Masure in Fauconnier and Masure (2004, p.499) retained Sepispinula ancorifera

Holotype: Cookson and Eisenack, 1960, pl.2, fig.11
Locus typicus: Carnarvon Basin, Australia
Stratum typicum: Albian-Cenomanian

Original description: Cookson and Eisenack, 1960, p.8
Shell sphaerical, densely covered with anchor-shaped appandages about 5-12Á long, the stalks of which narrow distally and divede into two slender, recurved branches with transparent tips. In some examples the impression is given that the tips of the appandages are united, but usually they are free from one another.
Dimensions: Holotype: overall diameter 70 Ám, diameter of shell 52 Ám. Range: overall 40-70 Ám, shell 30-52 Ám.