Ammonidium Appendix A
From dinoflaj2
AMMONIDIUM Lister, 1970, p.48-49. Emendations: Le Hérissé, 1989, p.80-81, as a revised diagnosis; Sarjeant and Vavrdova, 1997, p.15. Acritarch genus. Type: Downie, 1963, pl.92, fig.6, as Baltisphaeridium microcladum.