This biconic mitrid species has a wide (W/L = 0.37) shell with the spire longer than the aperture (S/L = 0.58). Spire sides are straight with about 5 teleoconch whorls. Spire whorl sides are convex and sutures are prominent with a slight convex shoulder. The protoconch has about 2 convex whorls. Body whorl sculpture is smooth above the periphery. Below the periphery, there are moderately prominent, closely spaced, convex spiral cords. Teleoconch early whorls have low axial riblets crossed by about 8 low, closely spaced spiral cords. The columella is without spiral folds. The callus on the concave parietal wall and columella are narrow and only slightly raised. The dorsal notch is moderate. The shell exterior is white to light yellow with large light brown to red-brown blotches that cross the whorls leavin narrow spaces between blotches. The interior of the aperture is colored similar to the exterior.

The species is very closely related to C. barbara, and has been separated on the basis of more slender, spindle-shaped form, smooth appearance and a thicker and more yellowish periostracum. Thiele described his species as having 8-9 whorls, the holotype of C. aglaia Tomlin, has 9 whorls and a specimen in the British Museum (NH) has only 7 whorls and a protoconch of 2 mamillate nuclear whorls. In the holotype of C. agulhasensis only the first post-nuclear whorl is clathrate, in the holotype of C. aglaia 3,5 post-nuclear whorls are clathrate and in the specimen in the British Museum (XII) 4 postnuclear whorls are clathrate. Usually the last 2,5 whorls are smooth, apart from feeble axial growth-striae and up to 20 oblique cords on the lower third of the body whorl. In all other respects the two species are very similar, and when more specimens will become available for examination, intergrading specimens connecting C. agulhasensis with C. barbara may come to light.

South Africa. From 80 to 200 fathoms.