Mantids: Mantodea

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MANTIDS: Mantodea

WANDERING VIOLIN MANTID (Gongylus gongylodes): SPECIES ACCOUNTS
ORCHID MANTID (Hymenopus coronatus): SPECIES ACCOUNTS
DEAD-LEAF MANTID (Deroplatys lobata): SPECIES ACCOUNTS
EUROPEAN MANTID (Mantis religiosa): SPECIES ACCOUNTS
CHINESE MANTID (Tenodera aridifolia sinensis): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

Mantids are fairly large insects, ranging in length from 0.4 to 6.7 inches (1 to 17 centimeters). The green, brown, or gray body color of mantids serves as camouflage to protect them from predators that hunt them for food. Species living in grasslands and meadows are usually pale yellowish brown or light green. Mantids found in leaf litter tend to be dark brown, while those found on or near flowers are yellow, white, pink, or light green.

Mantids are easily recognized by their large and spiny front legs held out in front of their bodies as if they were in prayer. The head is usually distinctive and triangular in shape. A few species have a single horn on the head. They have both well-developed compound eyes, each with hundreds of lenses, and three simple eyes, each with only one lens. The chewing mouthparts are usually directed downward. The antennae (an-TEH-nee), or sense organs, are long and threadlike. The head is attached to a very thin, flexible neck and is capable of turning nearly all the way around.

The first part of the midsection, or thorax, is usually long and slender and bears the raptorial (rap-TOR-ee-all), or grasping, front legs. The front legs are armed with one or two rows of short, sharp spines used to stab and hold prey, or food animals, securely. The remaining four legs are mostly long and slender. Mantids usually have four wings. The front wings, or forewings, are slightly thickened and have very fine veins. The hind wings are fanlike in shape and are carefully folded beneath the forewings. Most adult mantids have a single "ear" located on their underside, in the middle of the thorax near the abdomen. The ten-segmented abdomen is tipped with a pair of short, segmented projections.

Males are typically smaller than females, sometimes only half their size. They generally have larger simple eyes and longer and thicker antennae than females, and their bodies are lighter and more slender. Their abdomens are completely covered by the folded wings. In females the abdomen is not quite covered by the wings. Mantids' closest relatives are cockroaches and, to a lesser degree, termites. Mantids are sometimes grouped together in another order with these insects.

GEOGRAPHIC RANGE

Mantids are found worldwide in warm and tropical climates. There are twenty-three hundred species worldwide, mostly in the tropical rainforests of South America, Africa, and Southeast Asia. Many species are restricted to small areas, but others are found on more than one continent, having been accidentally introduced by humans to continents outside their range. Twenty species live in the United States and Canada.

HABITAT

Mantids are found only on land in rainforests, dry forests, undisturbed and second-growth forests, or forests that grow naturally after cutting or a fire, grasslands, and deserts.

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The "ear" of adult mantids acts as an early warning system, allowing them to avoid predators as they fly through the night air. Some mantids are able to hear the ultrasonic echolocation signals used by bats to locate flying insects. Upon hearing a bat, these mantids roll sharply and enter into a spiral dive to avoid being captured. They increase their speed as they drop to the ground or disappear into tangled vegetation.

DIET

Mantids will eat any small animal they can catch, including other mantids. They usually attack bees, butterflies, grasshoppers, and other insects, as well as spiders. On rare occasion they will attack small mice, lizards, frogs, and birds. They generally choose prey their own size or smaller. Right after hatching, mantid larvae (LAR-vee), or young, spend their first few weeks eating their brothers and sisters, aphids, and other small insects.

BEHAVIOR AND REPRODUCTION

Most mantids sit quietly and wait for prey to come within reach, but a few species actually chase down their victims. They have excellent vision and extremely quick reflexes and so are able to strike at and successfully capture insect prey in as little as one-twentieth of a second. After feeding, they always spend a great deal of time grooming. They use their forelegs to wipe their eyes and heads, while their legs and antennae are cleaned with the mouth.

Males spend much of their time searching for mates, while females spend most of their time hunting for food and looking for suitable egg-laying sites. In some species adult females use pheromones (FEHR-uh-moans), special chemicals that attract males as mates. Females require a large food supply so their eggs will develop properly. Therefore, they are usually found on or near flowers that attract large numbers of wasps, bees, butterflies, and other insect prey.

Mating may last for up to one hour. During this time the male deposits his sperm packet directly into the body of the female. It is a well-known myth that the female always bites off the head of the male while they are mating. Occasionally, a female may attack and eat a male as he approaches her or during or just after they mate, but this does not happen all the time. Hungry females are more likely to eat their mates.

MAGICAL MANTIDS

Mantids have captured the imaginations of people for thousands of years. They often appear in illustrations, paintings, and stories. It was once thought that, with their front legs held as if to pray, they could help direct travelers to find their way home. The Chinese staged fighting contests between mantids to bet on which insect would survive the battle. And there is a style of kung fu, a type of martial art, that mimics the movements of mantids.

Ten to two hundred eggs are deposited inside a foamy egg case that soon hardens into a protective, papery coating. The egg cases are attached to branches, walls, and other objects, and the adults die soon afterward. The young mantids hatch the following spring. They will molt, or shed their hard outer coverings, six to nine times before reaching adulthood. In cooler regions only one generation of mantids is produced each season, but in the tropics several generations may overlap every year.

MANTIDS AND PEOPLE

Some mantids are sold as pets and have become popular display animals in insect zoos. Another species is used extensively as a means of controlling plant pests without the use of harmful poisons. Throughout the United States people buy egg cases in the winter at nurseries and place them in their gardens to hatch in spring. However, young mantids will eat anything they can catch, including helpful insects as well as garden pests.

CONSERVATION STATUS

One species of mantid is listed by the World Conservation Union (IUCN) as Near Threatened, or likely to become threatened in the near future. There is very little information on most mantid populations; the greatest threats to them are habitat destruction and misuse of pesticides.

WANDERING VIOLIN MANTID (Gongylus gongylodes): SPECIES ACCOUNTS

Physical characteristics: Males measure 2.8 to 3.1 inches (7 to 8 centimeters) in length, while females are 3.1 to 3.5 inches (8 to 9 centimeters). They vary from light to dark brown in color. The head has a cone-shaped horn on top. The first section of the thorax is extremely thin and expanded into a diamond shape just before the head. All of the legs have leafy structures. The antennae of the females are threadlike, while those of the males appear feathery.

Geographic range: This mantid is found in southern India, Sri Lanka, Thailand, and eastern Java.

Habitat: This species lives on land in undisturbed and second-growth rainforests.

Diet: This species eats any insect that it can catch.

Behavior and reproduction: Their color and the leaflike extensions on their legs camouflage them against backgrounds of leaf litter and shrubbery.

Their egg cases contain from fifty to one hundred eggs. The egg cases are deposited on woody stems and hatch after several weeks.

Wandering violin mantids and people: This species does not have any effect on people or their activities.

Conservation status: This species is not listed by the World Conservation Union (IUCN). However, its habitat is threatened with destruction due to human overpopulation. ∎

ORCHID MANTID (Hymenopus coronatus): SPECIES ACCOUNTS

Physical characteristics: Adults are white with pink patches on the head, forewings, and legs. Females average 2 inches (5 centimeters) in length, while males are only half the size at 1 inch (2.5 centimeters). The eyes are cone-shaped and stick out beyond the outline of the head. Their legs have leaflike projections.

Geographic range: This mantid is found in Southeast Asia.

Habitat: This species lives on land in undisturbed and second-growth rainforests.

Diet: They eat any small insect or spider they can catch.

Behavior and reproduction: This species is typically found on or near flowers, waiting to ambush prey. During courtship, males tap their antennae against the forewings of the females, probably as a way to show they are ready to mate.

The long, narrow egg cases are 2 inches (5 centimeters) long and are attached to the stems and branches of plants and shrubs. The larvae have red bodies and black heads when they first hatch and mimic, or look like, ants because ants defend themselves with bites, stings, or bad-tasting chemicals and are usually not eaten by predators.

Orchid mantids and people: This is a popular species among insect hobbyists, people who enjoy the challenge of raising interesting and unusual insects.

Conservation status: This species is not endangered or threatened. ∎

DEAD-LEAF MANTID (Deroplatys lobata): SPECIES ACCOUNTS

Physical characteristics: Adult males are 2.5 inches (6 centimeters) long, while the females are about 2.8 inches (7 centimeters). They use a special kind of camouflage called crypsis (KRIP-sis), with bodies that resemble not only the color of dead, dry leaves but also their shape and texture. Their bodies are light gray to dark brown with faint spots. The midsection is expanded to the sides and shaped like a leaf. Their middle and hind legs have leaflike expansions, giving them an even more leafy appearance.

Geographic range: This species is found in Southeast Asia.

Habitat: This species lives on land in undisturbed and second-growth rainforests.

Diet: They eat small insects and their relatives.

Behavior and reproduction: This species lives in leaf litter and on shrubs. When threatened, they flash the bright colors on the insides of their front legs and expose the eyespots underneath their forewings, all in an effort to startle predators.

Females lay egg cases on twigs, which take about thirty to fifty days to hatch.

Dead-leaf mantids and people: This is a popular species among insect hobbyists. They are sometimes featured in insect zoos as examples of unusual coloring.

Conservation status: This species is not now endangered or threatened. However, the destruction of their habitat remains a threat to their widespread populations. ∎

EUROPEAN MANTID (Mantis religiosa): SPECIES ACCOUNTS

Physical characteristics: Adult European mantid males range in length from 2 to 2.5 inches (5 to 6 centimeters), while the females are 2.5 to 3.2 inches (6 to 8 centimeters). They vary in color from light green to brown. The inside of each foreleg has a distinctive bull's-eye-like spot.

Geographic range: This species is distributed throughout southern Europe, sub-Saharan Africa, temperate Asia, Australia, the northeastern United States, and Canada.

Habitat: The species prefers living in open fields and meadows.

Diet: They eat small insects.

Behavior and reproduction: European mantids are usually well hidden among low shrubs. They are strong flyers and are attracted to bright lights at night.

Each egg case contains from fifty to one hundred eggs. The cases are laid in fall and are attached to low grasses and on rocks or buildings. The larvae hatch the following spring.

European mantids and people: This species does not have any effect on people or their activities.

Conservation status: This widespread species is not endangered or threatened. They are slowly expanding their range in North America. ∎

CHINESE MANTID (Tenodera aridifolia sinensis): SPECIES ACCOUNTS

Physical characteristics: The Chinese mantid is the largest species in North America, with adult females reaching 4 inches (10 centimeters) in length or more. They are green, brown, or gray, with a distinct pale green border along the edges of their forewings.

Geographic range: This species is found in temperate eastern Asia, eastern United States, and California. They were deliberately introduced into the United States in 1896 to control insect pests.

Habitat: They prefer living in open fields and meadows.

Diet: They will eat any insect or spider that they can catch.

Behavior and reproduction: They are typically found on green, leafy plants and shrubs. Adult females are especially fond of perching near flowers, where they wait to ambush prey.

Each egg case contains one hundred to two hundred eggs. The egg cases are attached in the fall to almost any surface, including leaves, stems, branches, fences, buildings, lawn furniture, and automobiles. The larvae hatch the following spring.

Chinese mantids and people: Gardeners buy their egg cases in an effort to control garden insect pests. They are also kept as pets.

Conservation status: This species is not threatened or endangered. ∎