As I noticed with this species, this species is a wait and ambush predator. In my observation, whenever I put a cricket in the enclosure, he does not go out and try to chase it. He waits until it comes near him in order for him to strike. For the female, its almost a different story, but she will take on an insect about 1/2 it's body length. With the Japanese boxer mantis it tends to take on multiple prey at once and it even results in it chasing the flies and even crickets half it's size (mantids are half an inch). This species grows to an inch (2.5 cm) max for females and 3/4's an inch (1.9 cm) for males. Normally with small mantids I think that they would run away when medium sized prey items get to them.
With the assassin bugs, I expected them to jump on crickets. But they didn't. So maybe they were well fed before I got them.