Xanthidium ramosus Ehrenberg, 1838

Originally Xanthidium, subsequently Spiniferites, thirdly Hystrichosphaera, fourthly Bion; see also Ovum hispidum (combination not validly published).
Tax. sr. synonym of Geodia? tripunctata Merrill, 1895, by implication, according to Sarjeant, 1964, who considered Geodia? tripunctata to be a tax. jr. synonym of
Hystrichosphaera furcata.
Tax. sr. synonym of Hystrichosphaera furcata (Ehrenberg, 1838) O. Wetzel, 1933,
according to Davey and Williams, 1966.
Tax. sr. synonym of Galea koryka Maier, 1959, according to Sarjeant, 1983.
Tax. sr. synonym of Hystrichosphaeridium echinoides Maier, 1959, according to Sarjeant, 1983.
Tax. sr. synonym of Areoligera birama Maier, 1959, according to Morgenroth,
1968 and Stover and Evitt, 1978.
Tax. sr. synonym of Spiniferites bulloideus (Deflandre and Cookson, 1955)
Sarjeant, 1970, according to Harland, 1977; however, Lentin and Williams, 1981 retained Spiniferites bulloideus as a separate species.
Tax. sr. synonym of Hystrichosphaeridium plicatum Maier, 1959, according to Sarjeant, 1983, who considered Hystrichosphaeridium plicatum to be a synonym of
Spiniferites ramosus ssp. gracilis (Davey and Williams, 1966) Lentin and Williams, 1973.
Tax. sr. synonym of Homotryblium distinctum Salujha and Kindra, 1981, by implication, according to Jain and Garg, 1982, who considered Homotryblium distinctum to be a tax. jr. synonym of the autonym Spiniferites ramosus ssp. ramosus. This is a cyst equivalent of Gonyaulax spinifera (Claparede and Lachmann, 1859) Diesing, 1866, according to Dodge, 1989.

Holotype: not designated.
Lectotype: Ehrenberg, 1838, pl.1, fig.5; designated by Davey and Williams, 1966
Age: Late Cretaceous