When scientists first discovered the megamouth shark in 1976 off the coast of Hawaii, it struck them as so bizarre that, to classify it, they created an entirely new genus and family.
Today, little is still known about the shark save for the fact that it has a large gaping mouth, which is indeed, very mega.
http://news.nationalgeographic.com/2017/07/rare-megamouth-shark-sighting-video-spd/