Norway to Cabo Verde, Azores and lusitanian seamounts; maybe also in Mediterranean but the shell can be easily confused with those of some local species. « Habitat: under stones in the lower part of the littoral zone, and hard ground in the laminarian and coralline zones » (J. G. Jeffreys: British conchology vol. IV, London 1867, p.267). Predator on sessile preys (sponges). Smooth protoconch, except some tiny radial folds below the suture. Original taxon: Murex tubercularis.

Jeffreys, p.266: « …the base of the shell (which is slightly excavated) is girded by 2 strong, rather broad and obliquely twisted spiral ridges, one just below the periphery, and the other very short and winding round the canal; occasionally the upper of the basal ridges is indistinctly beaded, and in that case the longitudinal ribs may be traced below it… »

« The animal crawls and swims actively and with apparent ease. When at rest, it spins a fine transparent thread, which issues from the opening in the centre of the foot-sole, its end being attached by the point of the foot to some foreign substance. » J. G. Jeffreys: op. cit. p.268.