Deimatic behavior is designed to intimidate predators and dissuade them from attacking. It typically involves the display of some conspicuous color or structure. It has also been called dymantic, frightening or startle behavior. Deimatic displays cause attacking predators to hesitate, and perhaps withdraw, thereby giving the prey animal a chance to escape. Deimatic behaviors occur in both aposematic and cryptic animals so that they can be either a genuine warning of unpleasantness or a bluff.
Many large praying mantids and phasmids have dramatic deimatic displays. These insects are typically cryptic but, if disturbed, they expose previously hidden brightly colored hind wings in a static display which is maintained for perhaps a minute or more. Large mantids also often expose bright colors on the inside of the forelegs and they may stridulate by rubbing the abdomen between the raised wings making a hissing noise. The large grasshopper Phymateus has a similar deimatic