Epitonium magellanicum: White color, with 7 ½ to 8 convex whorls, each one grooved by thick, slightly oblique, axial growth lamellas. Each lamella presents superior angularity, which is clearly distinguished in the lamella of the aperture. The base is grooved by a more or less noticeable spiral cord. Distinguished from the species E. georgettinum Kiener, 1939, which is noticeably thinner and narrower, with a more sunken aperture, and does not present the mentioned superior angularity in the lamellas. The synonymy between E. magellanicum and E. latecostatum is given because no defined forms exist for either species; some authors propose different numbers of whorls on the spire (e.g. Castellanos 1990) whereas others report a spiral cord at the base (Forcelli 2000). Nonetheless, an examination of a batch of numerous specimens revealed diverse degrees of development in the whorls and spiral cords, for which high variability is assumed.

Epitonium magellanicum: In Chile, reported to 45ºS (Osorio et al. 2006), as well as in the extreme south, including Punta Arenas and Puerto Harris (Powell 1951); also at Cape Horn, Canal Beagle, Falkland/Malvinas Islands, Isla de los Estados, and Burdwood Bank (Castellanos 1990), from 105 to 545 m depth (Powell 1951). These new records are the farthest north (42ºS) in Chile.