Sea Facts:

Scorpionfish are so successfully adapted to hiding on the seafloor bottom that their swim bladders have atrophied. They can barely swim.  Instead, they lie in the sand, partially buried, camouflaged from passing fish. When an unwary victim swims by, the scorpionfish lunges out and sucks in its prey with an explosive gulp.

The ability to blend into the surroundings is an adaptation called crypsis.  However the scorpionfish can also announce its presence by flashing red as a warning.

See  comparison:  lionfish