Murex tribulusMurex tribulus, the caltrop murex, is a species of large predatory sea snail, a marine gastropod mollusc in the family Muricidae, the rock snails or murex snails.DescriptionThe shell of Murex tribulus can reach a length of. This quite common snail has a shell with a very long siphonal canal and numerous very long, fragile and acute spines, providing protection against predators. It feeds on other mollusks.DistributionThis species is widespread from Central Indian Ocean to Western Pacific Ocean.