Megamouth shark to be the sole extant species in the distinct family Megachasmidae, though suggestion has been made that it may belong in the family Cetorhinidae, of which the basking shark is currently the sole extant member. Researchers have predicted the feeding patterns of megamouth sharks in relation to the other two planktivorous sharks; the three plankivourous sharks have ram feeding in common, as it evolved from ram feeding swimming-type ancestors that developed their filtering mechanism to capture small prey like plankton. In addition to the living "M. pelagios", however, two extinct megamouth species – the Priabonian "M. alisonae" and the Oligocene–Miocene
Fish decoy then “swim” or "dangle" the decoy to attract a fish in close enough to spear. Another form of decoy that is sometimes used is called a “floater”. This type of fish decoy is not weighted, but is attached to a weight that holds the decoy at the desired depth. There are other fish decoys which have one or more hooks attached. In Minnesota, and some other states, these decoys are illegal and are referred to as "cheaters". In Michigan, a hooked decoy is legal and is simply counted as one of the number of lines that each angler is allowed