From Fensome et al., 2019:
Xenicodinium echiniferum Stover and Hardenbol, 1994, p.40–41, pl.7, figs.44a–c,45a–c.
Holotype: Stover and Hardenbol, 1994, pl.7, figs.44a–c.
Age: Rupelian.

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Original description: Stover and Hardenbol, 1994:
Proximochorate subcircular cysts; outer surface of autophragm very faintly ornamented and bears numerous, nontabular, smooth, solid, distally tapered spines with acuminate tips.
Spines 8.5 to 12 µm long.
Archeopyle precingular, operculum monoplacoid and secate.

Dimensions/Size:
intermediate; overall diameter 54 to 61 µm, body diameter 35 to 39 µm.

Remarks:
Assignment of this species to Xenicodinium is with reservation: it lacks the punctoreticulate ornamentation and the fibroid proximal expansions of the processes characteristic of species of Operculodinium Wall 1967. The species also differs from those of Exochosphaeridium Davey et al. 1966 by having smooth processes and by lacking a distinctive apical structure.

Comparison/Affinities:
Xenicodinium echiniferum differs from X conispinum by having spines rather than coni.