Shell up to 34 mm (about 1,5 inches) in length, but rarely exceeding 27 mm (about 1 inch), globose, acuminate at both ends and solid, sutures weakly impressed. Whorls 7-9, apart from protoconch which is usually eroded, sculptured with prominent, elevated and angulate spiral cords which number from 3-4 on the penultimate and up to 20 on the body whorl; the interspaces are deep, "V-shaped, axially prominently striate and equal in width or broader than the spiral cords. Aperture longer than the spire, very narrow and smooth within; outer lip very thick and prominently crenulate, crenulations decreasing in size anteriorly. Columella calloused and with 3-4 folds, first posterior fold very large, last anterior fold small; siphonal fasciole straight or sometimes recurved, occasionally weakly calloused, siphonal notch prominent. Reddish-orange to dark blood-red in colour, ornamented with an interrupted, white or yellowish-white central band on the body whorl, and a few spots upon the ribs above and below the band; in some specimens the spiral ribs are lighter than the base colour. Aperture and columella orange-brown, tip of spire frequently white. Periostracum thin and brown in colour. Height 27.4 Width 15.2 Height of aperture17.3 mm

The species is similar to M. chrysalis Reeve, but differs in being less obese and pupiform in shape, the spire is more acuminate, the whorls longer and aperture shorter. In M. chrysalis the sculpture consists of narrow spiral grooves which produced broad and flat cords on the centre of the body whorl, whereas in M. cucumerina the cords are elevated and angulate, and the interspaces between the cords are broad and "V"-shaped.

Red Sea to Polynesia and the Hawaiian Islands. On reefs, under coral and in crevices, from the intertidal zone to a depth of 10 fathoms.
RED SEA: Eilat, Gulf of Aqaba (Haime coll.; Peled coll.; Steiner coll.; Cernohorsky coll.); 20 mi. N. of Jid-dah, Saudi Arabia (USNM). EAST AFRICA: Mogadiscio, Somalia; Mocambique, Mozambique (both USNM). INDIAN OCEAN ISLANDS: Felicite I., Seychelles I. (USNM); Mauritius (USNM; DMNH; Powell coll.); Flat Island, Mauritius (ZMC); Tanikelv I., W. of Madagascar (AMNH). THAILAND: reef Ao Rawai, Ko Phuket; Goh Phi Phi (both USNM); Phuket Island (Cernohorsky coll.). INDONESIA: N. shore of Toba I., N. end Aru I., 1-2 faths.; Tg. Nama, S. side of Ambon Bav, Ambon I. (both WAM). PHILIPPINE ISLANDS: Cabra I., Lubang I., Mindoro (USNM; Del. Mus. N.H.); Subic Bav, Luzon; Palawan Islands (both Clover coll.). MARIANAS: Saipan Island (USNM). CAROLINE ISLANDS: Ulithi Atoll (USNM). MARSHALL ISLANDS: Kwajalein Island (AMNH). NEW GUINEA: Taurama reef, Port Moresby (Kleckham coll.); near Hollandia; Finschhaven (both AMNH). AUSTRALIA: Yeppoon, Queensland (Marrow coll.); Wilson Island, Queensland (USNM); Barrow Island, W. Australia (WAM). SOLOMON ISLANDS: Bougainville (Clover coll.); Marau Sound, Guadalcanal (Cernohorsky coll.); Malaita I. (DMNH). LOYALTY ISLANDS: Lifu (AIM); Islot Deguala, Uvea (USNM). GILBERT & ELLICE ISLANDS: reef-flats at Nukulaili, Ellice I. (USNM); Bikenibeu, Tarawa I., Gilbert I. (Cernohorsky coll.). WALLIS ISLANDS: E. of Nukuhifala; Faioa (Both USNM). FIJI ISLANDS: Cuvu Beach, S.W. Viti Levu; St. Annes, Nadroga reef, S. Viti Levu; Rat Tail Passage, Suva reef, S. Viti Levu (all Cernohorsky coll.). TONGA ISLANDS: Nukualofa (USNM; Cernohorsky coll.). SAMOA ISLANDS: Vaotoa, Vailele Bay, Upolu I. (USNM; Powell coll.); Ofu, Manua group; outer reef at Apia* Asau harbour (all USNM); Watson's Isle; Fagali'li, Upolu I. (both Powell coll.); Mulinuu, W. of Apia (Cernohorsky coll.). COOK ISLANDS: Penrhyn Island (AMNH); Rarotonea (Powell coll.). AUSTRAL ISLANDS: Matarau, Tubuai I. (USNM). SOCIETY ISLANDS: Hot Tipaemano, Raiatea; Papapara, Tahiti; Motu Pahare, Huahine; Moorea (all USNM); Point Venus, Tahiti (Clover coll.). GAMBIER ISLANDS: Hot Tarauroa, Mangareva (USNM). LINE ISLANDS: Fanning Island (DMNH: AIM); Jarvis I. (DMNH). PALMYRA ISLAND: (DMNH; USNM). HAWAIIAN ISLANDS: off Makua, Oahu, 7-8 faths. (Deynzer coll.); Shark's Bay (Leehman coll.); Honokowai, Maui (USNM); Mokolea Rock, Kailua Bay, Oahu, 10 faths. (AMNH; Cernohorsky coll.); Honolulu Harbor (AIM). MIDWAY ISLANDS: (USNM).