Hystrichosphaeridium leptodermum Maier, 1959

Originally Hystrichosphaeridium, subsequently Hystrichosphaera, thirdly Spiniferites.
Tax. jr. synonym of Achomosphaera alcicornu (Eisenack, 1954) Davey and Williams, 1966, according to Sarjeant, 1983.
Holotype: Maier, 1959, pl.33, fig.5; Sarjeant, 1983, pl.1, fig.2, pl.6, figs.1-2, pl.7, fig.4
Age: Middle Oligocene-Late Miocene