Operculodinium crassum

crassum Harland, 1979b, p.536, pl.2, figs.12–14.  Holotype: Harland, 1979b, pl.2, figs.12–14.  Taxonomic senior synonym: Hystrichosphaeridium (as Operculodinium) israelianum, according to Harland in Head and Wrenn (1992, p.20) — however, Head (1996b, p.1231) provisionally retained Operculodinium crassum.  Williams et al. (1998, p.441) incorrectly indicated that Head (1996b, p.1231) questioned the assignment of this species to Operculodinium.  Age: late Miocene–early Pleistocene.

Parent: Operculodinium