Tobacco hawk - features of reproduction and content of an exotic insect

Hornworms are insects from the Lepidoptera family. These are large and medium butterflies with an original color. They are heat-loving insects, but during migration they fly north of their usual habitat regions. In the world there are more than 1 thousand species belonging to this family. Tobacco shredder is widespread on the American continent. Insect caterpillars feed on tobacco leaves and related crops (tomatoes, potatoes). Butterflies quickly breed in captivity and are used by scientists as a model organism to study wildlife.

Insect description

Tobacco hawk or Manducasexta belongs to the family Hornwort, subfamily Sphinx. The adult moth has narrow wingspan of up to 100 mm. The front wings are much longer than the hind wings. The color is gray with brown patterns; white and black stripes alternate on the hind wings. A characteristic feature of the species are bright yellow or red squares on the abdomen. The butterflies have long antennae, the sucking mouth is the proboscis. They are nocturnal, traditional for moths.

Insects are pollinators of plants. They find flowers for food by smell, catching it hundreds of meters. Extraneous aromas disorient the butterfly. In search of food and a breeding partner, hawks can fly up to 100 km.

Interesting fact. During feeding on nectar, the hawthorn butterfly behaves like a hummingbird. She does not sit on a flower, but hangs over it, quickly flapping its wings. She produces nectar with the help of a long proboscis.

Butterfly's homeland is the tropical regions of America, some insect subspecies have spread to the Galapagos and Antilles, Jamaica. The northern boundary of the habitat reaches Massachusetts. In the USA, the butterfly is called Brazhnik Caroline and tobacco hornworm. Brazhnik caterpillars feed on leaves of tobacco, tomatoes and potatoes, less commonly found on eggplant and pepper.

Information. The Braconidae wasps are the natural enemies of caterpillars of the tobacco hawthorn. They lay eggs in the body of insects, controlling their numbers. White silk wasp cocoons look like large eggs.

Life cycle and reproduction

The life cycle of tobacco shred is 30-50 days. During this time, a complete transformation occurs:

• egg;
• larva;
• pupa;
• imago.

Reproduction of insects bisexual. Females are ready for fertilization a week after entering the adult age. Males during their life are capable of multiple mating. Fertilization occurs during night flights. Butterflies of opposite sexes hang in the air, touching each other with the ends of the abdomen. Mating lasts several hours.

In late spring, females lay eggs on the underside of the leaves of fodder plants. Their eggs are round in shape, 1 mm in diameter, greenish or transparent. After 2-5 days, larvae appear from the masonry.

Information. For a year, two generations of insects are replaced, in tropical latitudes - up to three or four.

Larvae and pupae

Brazhnitsa larvae are phytophages; their diet consists of leaves and fruits of nightshade plants. On the thoracic segment they have 3 pairs of legs, and on the abdomen another 5 pairs. A striking feature of the larva is the red horn located in the back of the trunk. Track length up to 80 mm, at birth - 6 mm. In nature, the caterpillar of the tobacco hawthorn is mainly protected green. It is ensured by the presence of organic pigments in the diet. When kept in captivity, they are fed wheat products, so the larvae are turquoise in color.

Interesting fact. Nicotine found in tobacco leaves is considered a poison for many living organisms. The caterpillars of the tobacco hawk adapted to the substance and learned to process it into safe compounds. Nicotine is used by insects as a defense against enemies, such as spiders.

On the body of the larva, 7 oblique transverse lines of white color are noticeable. Also on the body is covered with a pattern of black dots. In its development, the caterpillar survives 5 ages. Its dimensions change after each molt. With poor nutrition, larvae often molt and grow longer. The average duration of the stage is 3 weeks.

The adult caterpillar of the butterfly of the tobacco of the brazhnik falls from the plant to the ground and burrows itself in a hole to a depth of 10-15 cm. Here it turns into a chrysalis. A large pupa 4-6 cm long has an elongated shape and a pronounced maxillary loop. Brown color. Under favorable conditions (at a temperature of 27 °), the pupal stage lasts up to 18 days. When conditions worsen, it falls into diapause. This condition can drag on for several months. In June, the number of insects in the diapause is 5%, and by August it increases to 90%. The reason for the inhibition of development is a reduction in the duration of daylight hours.

Damage to agriculture

Larvae of tobacco hawthorn cause significant damage to tobacco plantations and tomato crops. They settle on the top of the leaves, eat them and green fruits. At a young age, pests merge easily with green plants, they are difficult to notice. They are usually found at the end of the larval period, when large caterpillars eat a large number of leaves. Insect killing activities are aimed at all generations. Natural enemies help control the number of pests.

The use of tobacco shred

Butterflies and caterpillars have found application in two areas: scientific and biological. They are used as objects for experiments and as pet food.

Model organism for research

Due to its large size, rapid development and simple maintenance, tobacco hawthorn has become a popular model organism. With it, scientists study the properties and processes of wildlife. The insect is especially widely used in neurobiology. Larvae open easily, their organs separate without any problems. For breeding, eggs washed in a disinfectant solution are taken. They are placed on the leaves of fodder plants or artificial substitutes.

Caterpillars - food for reptiles

Fans of exotic reptiles breed tobacco crab caterpillars as food for their pets. The body of the larva contains calcium, protein and moisture, which is necessary for the full development of reptiles. In the warm season, the caterpillars are fed with nightshade leaves: tomatoes and potatoes. In winter, they give special food based on wheat germ. Adult larvae up to 10 cm long are suitable for large reptiles, smaller specimens are bought for small lizards. When caterpillars are kept, humidity conditions must be observed. The lack of water in the public domain will lead to their dehydration.

One caterpillar in nutritional value replaces 3 locusts, the undoubted advantage of the species is the absence of a hard chitinous shell. For breeding, larvae are bought in special plastic boxes with a net. In pet stores, special food is sold, which is bred according to the instructions. Before pupation, a coconut substrate is poured into the container, into which the caterpillar immediately burrows. The soil is periodically moistened.Butterflies will need a more spacious container, a plant for sitting during the day and honey syrup for nutrition. After mating, the females lay their eggs and die soon, the males live another 2 weeks.