Murex is a genus of medium to large sized predatory tropical sea snails. These are carnivorous marine gastropod molluscs in the family Muricidae, commonly called "murexes" or "rock snails". The common name murex is still used for a large number of species in the family Muricidae which were originally given the Latin generic name Murex in the past, but have more recently been regrouped into different newer genera. The word murex was used by Aristotle in reference to these kinds of snails, thus making it one of the oldest classical seashell names still in use by the scientific community.