Neonorthidium*perforatum Marheinecke, 1992, p.117–118, pl.26, figs.12–14; text-fig.23.

Holotype: Marheinecke, 1986, pl.22, figs.1–2,4, as Northidium perforatum (name not validly published); Marheinecke, 1992, pl.26, figs.12–14; text-fig.23. Originally Northidium (name not validly published), subsequently (and now) Neonorthidium. Contrary to the opinion of Lentin and Williams (1993, p.447), Williams et al. (1998, p.421) considered this name to be validly published. Age: late early–early late Maastrichtian.

Original description: Marheinecke, 1992, p.118
Two-layered, cavate dinoflagellate cyst. Endoblast sphaeroidal to ovaloidal. Wall thick, weakly granulate. Periblast sphaeroidal to ovaloidal, regular fields indicated by sharp folds. Wall thin, transpatent. Contact between endo- and periblast at the archaeopyle margin and in the dorsal and ventral regions, further periblast clearly delimited from endoblast. Periblast weakly granulate. One of the fields (?ventral side) clearly differs from the others. It is ¦ six-sided, weakly transparent, stronger granulate and at the margins irregulary perforate. Archaeopyle: Apical, according to archaeopyle margin 1"+2"+3"+4". Operculum secate, ?foederate. Areation: Indicated by archaeopyle and presumably by fields on periblast.
Dimensions: periblast: length 48(54)57 µm, breadth 55(63)66 µm. Endoblast: breadth 37(54)57 µm, length 36(39)42 µm.