Praying mantises are beneficial insects that you may see in your Chicago garden in late summer. There are over 2,400 species worldwide and 14 families have just been discovered. They enjoy grasslands, forests, ditches and gardens in tropical and temperate climates. Members of the eighteen North American species feel at home in the Chicago area. Welcome them because they are ‘garden good guys’.
The name ‘mantis’ comes from the Greek word manikos which means soothsayer or prophet. Members of the Mantis religiosa family are named ‘praying’ because they assume a prayer-like posture with their forelimbs. They look like 2-4 inch green or brown twigs, but in some tropical regions they can be pink or white. They have two long antennae on a triangular-shaped head. Two, lateral compound eyes permit them to see images and colors. Three, simple eyes between the compound eyes provide data on light and darkness. They have a visual range of over 20 yards.
A movable joint between their head and pro-thorax enables mantises to turn their head around to cover their backs. The elongated thorax contains two grasping, spiked forelegs. The remaining portion of the thorax contains four other legs and two sets of wings. An auditory organ in their thorax enables them to effectively avoid bats during nocturnal flights.
Mantises and their nymphs are long, lean and alert masters of disguise, hiding in the foliage of grass, flowers and shrubs, waiting motionless for any hapless insect. They have quick reflexes and use their ‘raptorial’ forelegs to hold and secure prey. They consume any insect, beneficial or not, and even other mantises if there is nothing else to eat. They fly away if there isn’t enough food. If their mate can’t fly away quickly, female mantises will devour it. Mantises aren’t poisonous and don’t carry diseases.