Shell of average size for genus, roughly cone-shaped, with elevated spire and sloping spire whorls; shoulder sharply-angled, slightly rounded, bordered with 8-10 knobs; body whorl ornamented with 4 widely-spaced rows of large rounded knobs, with one below shoulder, one around mid-body, one around anterior end, and one small row around base of siphonal canal; rows of knobs and intercalated areas ornamented with 8-10 large, raised spiral cords; parietal shield proportionally large, well-developed, adherent, extending over at least half of shell base; parietal shield covered with very numerous tiny rounded pustules; labrum thickened, smooth, with inner edge being lined by 12-14 large teeth; shell color dirty white or pale tan, covered with very numerous dark brown speckles and small flammules, with largest and darkest flammules being on spire whorls; spiral cords of body whorl marked with evenly-spaced dark brown or blackish-brown dots, giving shell a heavily mottled appearance; aperture and parietal shield pure white; protoconch white, projecting and mammilate, composed of 3 whorls.

This uncommon species has a smaller range than does its closely-related congener, Morum oniscus, being most frequently-encountered in the western Caribbean region, from eastern Quintana Roo and Belize to Honduras. Morum strombiforme differs from M. oniscus in being a larger and more elongated shell with a much higher and more protracted spire and in having distinctly sloping spire whorls. Morum strombiforme is also a much more heavily-sculptured shell, being ornamented with numerous very strong, raised spiral cords that overlap onto the rows of rounded knobs, giving the shell a rougher appearance. While Morum oniscus is generally a pale-colored or white shell with scattered tiny brown dots, Morum strombiforme is consistently a much darker-colored shell, being covered with dense clumps of large dark brown or black dots and large amorphous dark brown flammules. In this last character, M. strombiforme somewhat resembles the dark-colored M. bayeri from Brazil, leading to the erroneous assumption that this species was also present in the Brazilian Province

The range of Morum strombiforme extends from the eastern half of the Yucatan Peninsula of Mexico, eastward along the coasts of Honduras, Nicaragua, Costa Rica, and Panama, and also throughout the Greater Antilles and the Virgin Islands. The species is most frequently collected along the coast of Honduras and the Bay Islands of Roatan, Guanaja, and Utila. Records of Morum strombiforme from Brazil are based on misidentified specimens of M. bayeri and M. berschaueri and the species does not occur within the Brazilian Province.