Shell shape and sculpture are very variable (de Aranzamendi et al., 2009). The species exhibits a conical morphology, dorsally raised shell, which is thick and non-translucent. The anterior part of the animal is laterally compressed. It has a large shell (maximum length 120 mm), which has a medium profile. The apex is located at the anterior 30-40% of the shell's length. All the slopes of the shell are convex. The aperture is oval to oblong. The surface of the shell is sculptured with numerous broad radial ribs and clearly defined concentric growth lines from the central zone towards the margin. The margin of the shell margin is highly crenulated. The external coloration of the shell is very variable across its distribution (pale reddish, brown, green with a bronze apex, grey, brown). The primary and secondary ribs are dark brown with clearer interspaces. The internal part of the shell has a soft metallic grey/brown interior with dark lines corresponding to external colour patterns, bordered by a white/brown halo. External anatomy: The ventral area of the foot is grey and the epipodial fringe is recognizable. The mantle fold is thick and cream-coloured. The mantle tentacles are in an alternated series of three shorter pigmented ones (white/black/white) and a black longer one. The cephalic tentacles are dorsally pigmented with a black line.

Shell of moderate size, up to 61 mm. (2,375 inches) in length, rather solid, tall conical, narrowly ovate, and with the apex at about the anterior third. Sculpture consisting of from 36 to 40 strong radial ribs, which are rendered strongly scabrous to nodular by numerous overriding concentric lamellose lirae. Colour yellowish-brown to reddish-brown, tending dark reddish-brown to bronze over the apical area. Interior silvery with a pinkish lustre, more or less rayed and mottled with reddish-bronze, the spatula and spotted marginal border dark reddish-brown.

The species is nearest allied to N. magellanica which is more broadly ovate in outline and lacks nodulation of the radials.

Southern Patagonia, Straits of Magellan, Tierra del Fuego and Falkland Islands.
Magellanic province. Pacific Patagonia: from Guarello Island (50°S) to Cape Horn. Atlantic Patagonia: Tierra del Fuego. Falkland/Malvinas Islands.
Habitat: Medium and low intertidal, subtidal rocky ecosystem between 0 and 40 m depths.
Our extensive sampling effort across Pacific Patagonia suggests that N. deaurata occurs in this region from Guarello Island (50°S) to Cape Horn. In the Atlantic coast this species was reported north up to Mar del Plata province (Morris & Rosenberg, 2005). However, according to de Aranzamendi et al. (2009) the distribution of the species in the Atlantic is restricted to Tierra del Fuego. This species is also abundant in the Falkland/Malvinas Islands.

Molecular analyses suggest that N. deaurata represents a single genetic unit along Pacific (Gonzalez-Wevar et al., 2011a) and Atlantic (de Aranzamendi et aL, 2009, 2011) Patagonia. Molecular and geometric morphometric comparisons (Gonzalez-Wevar et al., 2011a) showed that N. fuegiensis is a synonym of N. deaurata. Similarly, molecular analyses indicate that N. delicatissima represents particular morphotypes of N. deaurata (contra de Aranzamendi et al., 2009). Molecular analyses (unpublished data) indicate that N. deaurata exhibits marked levels of population genetic differentiation between Patagonia and the Falkland/Malvinas Islands.