Last update 28/04/2007

Preying (or praying) mantids are among the most fascinating of all insects. They are easy to recognise: two front raptorial legs, four walking legs, triangular head with big eyes, a thin thorax and bulky abdomen with four wings. Their penetrating staring and the typical hunting positions with raptorial legs kept together under the head, like the arms of a praying man, made it a sacred creature for many ancient cultures. In Africa bushmen tell mantids can indicate the correct way to lost voyagers with legs and Chinese monks even developed a kung fu martial art style, the Tan Lang, inspired by the mantis attack moves.

These insects can be found in every tropical and subtropical area and belong to the class Insecta, order Mantodea, counting more than 2000 species from the size of a fly to giants of more than 15 cm . Almost all mantids species eat a lot: grasshoppers, crickets, flies, sometimes hornets and spider are taken. Mantids are not particularly selective with prey. They are mainly diurnal ambush predators that seize anything smaller than they are, and sometimes of similar or bigger size. Therefore they have a massive effect on insect population and attacks on birds, mice, snakes, frogs are quite common in nature.

Females are bigger than males and most of the time, because of their weight, are not even able to fly or are wingless Males are often decent aviators, able evade bats during their night flights, when they roam around in search of females. They employ a particular single ear located in their bellies, able to detect bat’s sonar hunting frequencies, exactly like modern combat aircraft’s radar warning receivers detect enemy radar emissions. A threat immediately elicits a defensive manoeuvre with a stall and an unpredictable dive in the ground to evade capture. 
The male should be cautious during mating and can sometimes be eaten in the process. But in many cases even if the female manages to grab him, he’s simply programmed to continue his copula without hesitation. Decapitated males are able to copulate since the portion of the brain that inhibits their sexual instincts is located in the head. Often headless specimens try to mate with any long and slender objects, like fingers and pencils. His sacrifice will not be vane anyway; it will ensure the satiated female will produce more and healthier eggs. Some species, like Theopropus and Hymenopus, have very small and agile males, capable of evading aggressive partners.
Pregnant females produce some dozen eggs week later in a foam container, the eggcase, that enables embryos to develop screened by adverse environmental conditions and many predators. The babies, similar to adults, grow fast and often are reach maturity in less than 4-5 months, shedding their skin to grow bigger. The adult insect won’t live for too much: the biggest females often do not reach a year of age.

Mantids are camouflage masters. The famous orchid mantis Hymenopus coronatus, during the course of its lives, features all mimicry and deceiving tactics. Young nymphs are very effective batesian mimics of assassin bugs (Reduvidae) with their vivid orange-black coloration. But then they turn whitish with all those floreal appendages, false petals and pistil-like head. Besides ambushing insects on orchids and flowers, they can even simulate to be flowers. Curious insects coming to investigate are easily captured. A perfect case of aggressive mimicry.
Even less spectacular and conventional species like Hierodula, Sphodromantis, Mantis, Tenodera disappear when placed between leaves and bushes of similar colours. But, as seen, other species are the ultimate camouflage masters. African Phyllocrania, Asian Deroplatys and South American Acanthops, are impressive imitators of dead leaves. Besides coloration their body feature many morphological enhancements like foliage appendages, nervations, crests above the head. Second and third instar nymphs of Phyllocrania even resemble black unpalatable ants.  The African Heterochaeta mimics sticks, often keeping forelegs in cross position, while Asian Humbertiella flattens on bark of big tropical trees. Others imitate flowers (Creobroter and Pseudocreobroter), green leaves (Rhombodera and Choeradodis) and even rocks and sand (Eremiaphila).
When discovered big mantids often make impressive threat displays, showing warning colours normally concealed. The big African devil's flower mantis Idolomantis diabolica performs an impressing parade, with long, colourful legs fully streched. But it’s a bluff since mantids are not poisonous, even if they can inflict painful bites and pinch with forelegs.