Pusia torotortum: Shell small, up to c. 9 mm in length and 3.6 mm in width, fusiform-ovate, rather solid. (The largest specimen known to us was living in an aquarium from February 2005 to March 2006 and reached a shell length of 11.4 mm.) Protoconch hemi-ellipsoidal-multispiral, 0.6-0.7 mm in length and 0.50-0.55 mm in width at the base, consisting of 3.0-3.5 smooth, well rounded, whitish to light yellow embryonic whorls.
Teleoconch of 6-7 strongly convex whorls, which are distinctly shouldered in some distance below the suture in some specimens. Suture moderately distinct, formed by a narrow, thin ledge of the younger whorl. Whorls axially and spirally strongly ribbed. Axial ribs as well as their interstices somewhat triangular in cross-section, numbering 15-17 on both the body whorl and the penultimate one; 11-13 on early whorls. Spiral ribs rounded, rather smooth, overriding the axial ribs where they become strongest and form nodules which give the whole shell a pustulate appearance. Spiral ribs number 3—4 on early whorls, 5-6 on the penultimate whorl, and 11-12 on the body-whorl, apart from the siphonal fasciole with four oblique densely arranged cords. Spiral grooves separating the spiral ribs narrow (only about half as wide as the spiral ribs), relatively deeply incised, axially striate. Aperture shorter than the spire (40-45% of total shell length in specimens with preserved apex), relatively wide and not constricted at the anterior end, with 8-10 strong nodulous lirations inside; outer lip simple and smooth. Siphonal canal very short and slightly recurved; anal notch wide and deep. Parietal side of aperture with a moderately thick callus near the posterior aperture angle, otherwise only slightly glazed; inner lip protruding only at the anterior end. Columella with four plaits, decreasing distinctly in size anteriorly.
Shell background colour white. With striking circular or slightly axially stretched red or reddish brown dots at the intersections of the spiral grooves with the tops of the axial ribs; some irregular faint flesh-coloured blotches below the periphery just above the sutures. Aperture and columella completely white.
The live animal has fine red dots on the white sole of the foot and on the proboscis; the anterior halfs of the eye-stalks arc completely red, the small black eyes standing out conspicuously.

Pusia torotortum: Vexillum (Pusia) torotortum has been confused with V. (P.) infaustum (Reeve, 1845).It resembles that widely distributed Indo-Pacific species in shell shape and colour pattern, but differs in more strongly convolute whorls and in smaller size: maximum shell length 9.0 mm in natural habitats, versus 11- 14 mm in V. (P.) infaustum. In the latter species the sculpture is comparatively weak (not pustulate), with flatter axial ribs and less incised and finer spiral grooves. The colour pattern of both species differs considerably in that the red dots at the intersections of the spiral grooves with the tops of the axial ribs are larger and partially axially elongated in V (P.) torotortum, and quite fine and partially spirally elongated in V. (P.) infaustum. The protoconchs of both species are very similar in size, form, number, and colour of the embryonic whorls.

Pusia torotortum: The species is known from the Seychelles, Maldives, and Similan Islands (SW. Thailand). At the Maldive Islands living specimens were found in subtidal zones, from 1 to 18 m depth, in thin layers of sand on limestone pavement or dead coral heads