Jawfish are aptly named with their huge mouths that seem to take up their entire head. These unique little fish also have large eyes, elongated bodies and unusual lifestyles.
Jawfish spend most of their time in their burrows, which they dig in the sand using their powerful jaws. They rarely venture far from their holes and will quickly disappear into their underground homes if they sense the slightest bit of danger.
Jawfish are found near coral reefs throughout the world where they mainly feed on plankton and other tiny creatures. Most species usually grow to between 4 to 6 inches, though some types can grow to 18 inches.
( These paragraph are taken from http://www.tropicalfish.at/saltwater/jawfish/jawfish.html)