Shell elongate, solid, with a last whorl more than half the total height of the shell. Protoconch of cream colour, smooth, shiny, with about 1,5 elevate whorls, the transition with the teleoconch being difficult to see; the diameter must be about 500 µm. Teleoconch with about 5,5 whorls which are smooth, shiny, almost flat in profile, and slightly stepped at the suture. Aperture narrow, columella S-shaped, with three small tubercles below and one on its upper part, external lip with 6 teeth, the third one the most prominent. Colour pattern whitish with brown lines which form irregular ovoids or small rounded shapes, which predominate below and above the suture; in the middle of the whorls the brown colour predominates. Dimensions: the holotype is 9.0 mm long.

Comparison must be made with the other Sao Tome species: M. inesitae Rolan, 2005 has a larger shell, the suture is not stepped, the protoconch brown, and the pattern more regular and formed by smaller rounded shapes.
M. saotomensis Rolan. 2005 has a smaller and obese shell with uniform pattern of smaller rounded shapes and a depressed protoconch.
M. tenebrosa Rolan, 2005 has more convex whorls, darker pattern, and a wider and darker protoconch.
M. aemulata Rolan. 2005 from Annobon Island is wider, lighter in colour, protoconch wider and with two dark bands.
Other west African species such as M. melvilli Knudsen. 1956 or M. africana Rolan, 2005 have a multispiral protoconch with 3,25 or 2,5 whorls respectively, which
represents a different planktotrophic type of development.

Type locality: Minerio Reef, Sao Tome, at 43 m, on bottom of small rounded stones. Distribution: Only known from the type locality.