Mitra cardinalis: Shell up to 70 mm (about 3 inches) in length, elongate-ovate, solid, plump and heavy. Sutures moderately impressed, whorls convex and rounded at sutures, numbering from 8-10 inclusive of the protoconch which consists of 1-2 white and glassy nuclear whorls. Postnuclear whorls with 3 spiral striae, penultimate whorl with 8-10 and last whorl with 22-30 spirals; spiral grooves are distinctly punctate on the body whorl but prominently axially lirate on the spire whorls. The axial lirae become less prominent on the centre of the last whorl. Aperture longer than the spire, slightly widening basally, smooth within; outer lip thickened, convex, and with about 20 small, brown-spotted denticles. Columella calloused anteriorly, forming a small shield in adult specimens, and with 4 or 5 prominent, oblique folds. Anterior canal short, with a moderate callus and 6-10 close-set, oblique cords, siphonal notch distinct. White in colour, ornamented with 3 or 4 spiral rows of irregular, rectangular or quadrate brick-red spots on the penultimate whorl and 10-15 rows on the last whorl; these spots may merge and form large blotches, especially on the spire whorls. Interior of aperture flesh or light yellow, columella creamy-white.
Measurements: Length between 43 and 70 mm, width between 19 and 30 mm

Mitra cardinalis: This species is easily recognized by its ovate and plump form, spiral rows of brick-red, quadrate spots, punctate spiral grooves, close-set axial striae and small, brown-spotted denticles on the outer lip.
Mitra lamarckii (Deshayes, 1832) from the Hawaiian Islands, has been considered by some authors to be a form of M. cardinalis, but the former species is closely related and a subspecies of M. nubila (Gmelin, 1791).

Mitra cardinalis: Range: Madagascar to Polynesia.
Habitat: On reefs, under coral rocks generally on a hard reef substratum but occasionally partly-covered with a thin layer of sand, within the intertidal zone.