Shell small, diameter between 0.4 and 0.7 mm, planispiral, of translucent white colour whith three brown lines, one on each side with the third in the periphery. Protoconch of 3/4 whorl with a prominent cord with serrated boundaries bordered externally by a depression, separated from the suture by another elevation. Surface is enterely covered with tiny perforations.
Teleoconch between 1 and 2 whorls with very elongated and slightly prominent tubercles (like ribs), numbering 25-29 on the first whorl. The interspaces between them arc bordered near the convexity by a submerged spiral cord which with continuous the protoconch canal In big specimens this sculpture is attenuated at the end of the spire. The whole teleoconch is covered with very fine striae, also present at the periphery, which is uniformly convex. Etymology. The specific name refers to the brown spiral lines of the shell.

The fine constant spiral striation and the periphery without any axial sculpture differentiate A lineofuscata sp. n. from A rota and A rotundata (Palazzi, 1988). A lygnea (Palazzi, 1988) has spiral cords and an uniform brown colour. A multistriata Rolan, 1991 from the Cape Verde Islands has tuberculated and different spiral cord, and A robusta Rolan, 1991 has prominent axial prominences and lacks the spiral brown line. The brown spiral line is present in A fischeriana (Monterosato, 1869), but the colour of the shell is not white and lacks the spiral striae.