Sharks and rays are one of the most successful fish groups, occupying most marine habitats including coastal, deep-sea, and pelagic zones. New shark species are still being discovered: about 157 between 2007 and 2013 against 199 over a much longer period (1970-1999). Moreover, the Western Indian Ocean (WIO) is a worldwide ‘hotspot’ in terms of the diversity of shark species after Australia. About 290 species of sharks have been identified in the WIO region.