Hystrichosphaeridium transculentum Sah et al., 1970

Now Achomosphaera. Originally Hystrichosphaeridium, subsequently (and now) Achomosphaera.
Stover and Evitt, 1978, considered this to be a problematical species of Hystrichosphaeridium.

Holotype: Sah et al., 1970, pl.2, fig.18
Age: Late Cretaceous