Shell large for the genus. The whorls are more convex and the shell usually more inflated than in the other species; Amati & al. say it is « nearly keeled at the periphery » (a feature that is very marked in juvenile), with weak spiral and axial sculpture. The spirals are less numerous than in other species, except for the stout pinkish deep-water morph. Colour usually light orange or beige, with darker spiral lines; base of the shell often more coloured; optionally, presence of « whitish subsutural blotches in correspondence with the axials. » – Amati, Smriglio & Oliverio: “Revision of the Recent Mediterranean species of Mitromorpha Carpenter, 1865 (Gastropoda, Conoidea, Mitromorphidae) with the description of seven new species”, Zootaxa 3931 (2), march 2015, p.170.

« M. wilhelminae is named after the “Pedagogische Academie Koningin Wilhelmina”, where the second author, much to his satisfaction, has been employed for many years. » – van Aartsen, Menkhorst & Gittenberger: “The marine mollusca of the Bay of Algeciras, Spain, with general notes on Mitrella, Marginellidae and Turridae”, Basteria suppl.2, p.42.