Well, I'll give you something official, Blackie Meow.= ==
I love reading Baidu Wikipedia. Ahem. = =+
Horseshoe bell snail
AKA: Horseshoe snail (horseshoe snail is also a collective name for this family of animals)
Latin name: Trochus niloticus
English name: Commercial Trochus; top shell
Shellfish: Gastropoda, Bellsnail superfamily, Bell snail family (Horseshoe snail family).
Introduction: Gastropoda (Gastropoda), Prosobranchia (Prosobranchia), Trochidae (horseshoe snails), marine mollusks, dwarf conical shell truncated at one end. Although the distribution range is from the intertidal zone to the deep sea, from the equator to the high latitude areas of the rocky shore in the shallow sea in the most species, the Atlantic coast temperate areas are common humpback snail genus (Gibbula), the genus of single-toothed snail (Monodonta) and the mouth of the snail genus (Calliostoma). The genera Tegula and Calliostoma are abundant in the Pacific. Tropical species such as Trochus, Tectus, and Cittarium tend to be larger and more colorful than species from other regions. Most species are phytophagous, feeding on algae or spore layers on rock surfaces. Dioecious, fertilized in vitro, most have free-swimming larvae. All have internal layers of true beads. The largest species is the large horseshoe snail (Trochus niloticus) of the Indian and Pacific Oceans, which was fished in large quantities in the past to make buttons with its shiny layer of true beads.
The largest and heaviest of the bell snails, with an almost equilateral triangular shape. The conch layer of most adult shells is roughly smooth except for some fine diagonal lines; the conch layer of the middle shells and all juvenile shells, have small tubular nodules, some of which form grooves at shallow suture lines. The conch-axis has ridged teeth. Shell surface pale pinkish-white, with broad diagonal stripes of dark red. (Note: Once used in the manufacture of buttons and still used in small quantities for ornamentation.)
Size: 11cm
Region of distribution: Tropical Indo-Pacific
Habitat: near coral reefs