Whale shark (Rhincodon typus). This is the largest fish in the world, reaching a length of over 12 metres and weighing up to 20 tonnes. It is a filter feeder, targeting swarms of plankton as well as shoals of fish and squid. This shark has a horde of attendant remora fish (Echeneidae), which attach themselves to the shark and feed on skin parasites and faeces. The whale shark inhabits tropical seas worldwide, and is a popular subject for divers where it comes close to land. Filmed in the Gulf of Thailand.