In most cases cannot recognize prey that is motionless. In certain instances can attack prey which has moved previously and they have already fixed on. In these cases may use olfactory cues as they will touch prey with antennae to smell it and then strike. Strike is very fast. Takes from 50 to 70 millisec.
Strike has to be fast.
The startle time or reaction time for a fly sitting or engaged in flight is 65 millisec. This is within the strike range of the mantid. Note that the strike is too fast to allow any corrections by the mantid after the strike starts. The mantid must gauge distance and direction before striking.