Shell up to 28.0 mm in length, fusiform-elongate, spire pointed, whorls only slightly convex and sub-angulate at sutures, teleoconch of 7-9 whorls, protoconch of 2.5 glassy-fawn embryonic whorls. Sculptured with prominently elevated spiral cords which number from 3-4 on the penultimate and from 10-13 on the body whorl, fourth cord on penultimate whorl usually covered by the suture; the interspaces are broad and sculptured with numerous axial riblets and rarely with an additional shallow and weak intermediate cord. Aperture longer than the spire, narrow, smooth within, outer lip prominently fluted on edge, columella narrowly calloused and with 4-5 prominent, oblique folds, siphonal notch distinct, siphonal fasciole with 4-6 finer, close-set oblique cords. Usually uniformly fawn to dark brown in color, some individuals with interrupted orange-brown lines on cords, interior margin of outer lip porcellaneous-white, interior of aperture coffee-brown.

This species appears to be intermediate between I. flammea (Quoy & Gaimard) and I. interlirata (Reeve). It is closer to the latter species in form, but has a longer, slightly more angular aperture posteriorly, broader spaces between the spiral cords and less inflated whorls, and is easily recognized by its uniform brown color and the coffee-brown apertural interior and white margin of the outer lip.

Range - From the Red Sea and the Persian Gulf to the Ryukyu and Samoa Islands.