Shell solid, biconical, slightly constricted around the upper part of each whorl. Whorls nine. Colour lavender-gray, with a broad peripheral band of buff descending the spire, and on the last whorl underlined by a single or double chocolate line; lip buff; interior ochraceous brown. Protoconch of two small helicoid whorls. Sculpture: The first whorl is keeled, and developes small radial ribs; on subsequent whorls the ribs amount to about ten, not continuous from one whorl to the next, bent, and thickened on the shoulder, thence quickly tapering to the suture, continuing in the opposite direction to the base of the last whorl; the whole shell is over-run by microscopic spiral threads, alternately larger and smaller. Aperture: The mouth is narrow, oblong, protected by a stout varix which ascends the previous whorl, and in which is excavated a shallow semicircular sinus ; the lip has a very narrow free margin, within which are about eight small inconspicuous teeth ; the columella is overlaid by a thick callus sheet with a definite margin, across it extend ten plications; canal a mere notch. Length 12 mm., breadth 4.5 mm.

This species is related to the New Caledonian E. guestieri, but differs in colour, the general tone being slate, not brown ; in being more slender, and having the ribs further apart. There is a general resemblance to E. reticulata, but E. arenivaga is smaller, with fewer and more widely spaced ribs. Both extremities of E. arenivaga taper more, and the body whorl is proportionately smaller.

Australia. Queensland.