Iotyrris devoizei: Shell height 17.8 mm, shell diameter 6.3 mm, last whorl height 9.0 mm, aperture height 5.9 mm. Shell conical, consisting of 7 teleoconch whorls, with high spire, shell diameter to shell height 0.35, aperture height to shell height 0.33, spire height to shell height 0.49. Protoconch overgrown and eroded, light brown, of more than 3 whorls, sculptured with closely spaced axial threads. Teleoconch whorls slightly convex, spire whorls slightly angulated on the periphery. Last whorl sharply narrowing towards attenuated, nearly straight, siphonal canal. Suture shallowly adpressed, slightly wavy. Subsutural ramp narrow, convex, with single bulging keel subdivided by two narrow and shallow grooves. The keel is strongly marked by rectangular, unevenly sized, dark red-brown spots. Immediately below the ramp are two narrow but tall, closely spaced, cords, forming the shoulder. Below them are three broadly spaced cords, equal to those on the shoulder, separated by smooth interspaces, except for one narrow thread between the lower shoulder cord and upper peripheral one. There are 5 more closely spaced cords on the shell base and 5 narrower and closer-spaced threads on the canal. Axial sculpture absent except for inconspicuous growth lines. Aperture narrowly oval. Outer lip broken; judging from the growth lines, anal sinus deep, situated on the shoulder. Inner lip nearly straight, columellar part straight, callus very narrow, not extending onto the parietal wall. Color creamy white, with strong, dark spots on the subsutural ramp; much lighter yellow narrow spots covering all the cords of the periphery; tessellate, closely spaced dark spots on the cords of the shell base; and smaller, slightly lighter spots on the threads of the canal.

Iotyrris devoizei: New Caledonia, Loyalty Islands, Vanuatu, shallow water, alive in 16-30 m, shells from 4-47 m. It is possible that the species also occurs in Hawaii and the Marquesas.