Oligosphaeridium macrotubulum (Neale and Sarjeant, 1962) Davey and Williams, 1966

Originally Hystrichosphaeridium, subsequently Oligosphaeridium, thirdly Oligosphaeridium?.
Tax. jr. synonym of Oligosphaeridium vasiformum (Neale and Sarjeant, 1962) Davey and Williams, 1969, according to McIntyre and Brideaux, 1980.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Oligosphaeridium.
Holotype: Neale and Sarjeant, 1962, pl.20, fig.7, text-fig.8a
Locus typicus: Heslerton, England
Stratum typicum: Hauterivian

Original diagnosis: Neale and Sarjeant, 1962, p. 452: Hystrichosphaeridium macrotubulum
A species of Hystrichosphaeridium having an ovoidal to sub-quadrate shell with a coarsely granular surface. The tubes connect directly to the shell interior and are open distally. They vary in thickness but are typically massive, tapering somewhat at base and tip but elsewhere or constant diameter. They open outwards at their distal extremity, giving rise to processes variable in number (2-6) and length but always pointed. Length of the tubes constantly greater than the smallest shell cross-measurement. No pylome developed.

Original description: Neale and Sarjeant, 1962, p. 453: Hystrichosphaeridium macrotubulum
Shell and spines pale yellowish-brown. Tubes very finely and irregularly perforate, frequently with a large lateral opening just above their base on one side and always with root-like extensions on the surface. The distal branches vary greatly in length and direction with relation to the shell surface. Number of tubes 18-24.
Dimensions: Type; overall 122 µm x 116 µm, shell 46.5 µm x 38 µm, spines 43.5-49 µm in length. Range: Overall (max.) 100 µm-120 µm.