Dautzenberg described this shell in latin and in french. Please click French flag.

Ce Trophon se distingue par le nombre considérable de ses varices ainsi que par son aspect crépu. L'exemplaire figuré n'a pas atteint son complet développement : il existe dans les matériaux rapportés par L’Hirondelle des fragments de la même espèce, qui prouvent qu'elle peut atteindre à une taille presque double de celle indiquée.

As already noticed by Houart (1981) the name richardi (= droueti) has recently been used by Mediterranean authors for shelf populations of T. muricatus or T. barvicensis. T. droueii can be distinguished from these populations by its broader outlines and its aperture, furnished with denticles on the inside of the outer lip. The development of spines from the axial lamellae is variable in the two forms and cannot be used for separation.
There is, however, some possibility that T. droueti should be considered only an isolated population or subspecies of barvicensis, which certainly is its closest relative. At present nothing is known about the occurrence of barvicensis or droueti on the sea-mounts between the Azores and Europe, which prohibits further speculation on the relationship.

Endemic to the bathyal area of the Azores; known only from the material examined.