Praying Mantis

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Praying Mantis

The praying mantis (plural praying mantids) is a carnivorous insects of the order Mantoidea (or Mantodea) named for its typical stance of an upright body with the two front legs held out in a pose of prayer. The long, thick, spiny, legs and the markedly triangular head with two large compound eyes make the mantis one of the most readily identifiable of all insects. The long neck of the praying mantis is actually the prothorax, which connects the head to the thorax and supports the front legs. Two other pairs of running legs attach to either side of the thorax, as do the wings, which lie folded over the slender, elongated body. The more than 1,800 species of praying mantids, range in size from 0.4-5.9 in (1-15 cm) long and are found in most tropical and temperate climates around the world.

Reproduction

Mantids’ reproductive organs are located at the tip of the abdomen. Many females are flightless and attract their mates by emitting a species-specific chemical, known as a pheromone. The male is much smaller than the female and performs a brief courtship ritual before alighting on the female’s back to mate. A popular misconception is that the female mantis attacks and eats the male after he has fertilized her. This is true in capitivity but rare in the wild; scientists are still unsure exactly why this phenomena occurs.

Female mantids deposit batches of between 10 and 400 fertilized eggs using their ovipositor at the tip of the abdomen. The eggs are secured to stems, leaves, or other surfaces, with each egg batch housed in an ootheca (egg case) constructed from a frothy substance produced in the abdomen. Each egg is deposited in an individual compartment inside the ootheca, and each compartment has a one-way valve permitting the young insects to hatch with minimal effort. The ootheca hardens quickly, providing protection from parasitic insects, birds, and the sun.

Some species of mantis, such as the African Tarachodula pantherina, construct long, narrow oothecas and guard their eggs lying over them. In about a month, wingless nymphs (young) emerge from the eggs, and look more like ants than mantids. This resemblance undoubtedly protects them from predatory birds, which seldom attack ants. Mantis nymphs are eaten by ants, which can wipe out an entire batch of young mantis nymphs. Surviving mantis nymphs molt several times, each time becoming more like the adult, with mature wings appearing after the final molt.

Preying

Praying mantid eat live invertebrates, including other mantids, although larger species have been observed to eat frogs, small lizards, and even small species of mice. The combination of camouflage, extremely flexible head movements, excellent binocularvision, speed, dexterity, accurate judgement of direction and distance mean that a mantid seldom miss their prey. Mantids turn their heads toward an approaching meal, they fling out their front legs at lightening speed, and secure the prey on hooked spines near the tip of each leg.

The mantids first chew off the head of the prey, before gnawing its way down the body, devouring every morsel. Decapitation of larger prey is seldom possible, so these are eaten alive. One large Australian mantis (Archimantis latistylus ) was observed to chew on a gecko (a small night lizard) for over 90 minutes, eating the entire animal, and leaving only the skull and spine. Mantids clean themselves meticulously after every meal.

Defense

Most mantids are green, brown, or gray, and sit motionless on a leaf, twig, or bark, camouflaged from predators such as birds, small animals, and other insects. The tiny South African flower-dwelling mantis, Harpagomantis discolor, can change color to match the flower. Scare tactics, which provide some defense