What are the characteristics of the occurrence of the bare shouldered star longhorn?

The bare-shouldered star beetle harms poplar, willow, truncatum truncatum, elm, sugar maple, horse chestnut, plane tree, etc. This insect is widely occurring in China, and it seriously harms poplar, willow, elm, etc. The affected xylem is hollowed out, and the trunk is prone to wind breakage or the whole plant dies.

Morphological characteristics] Adult.

body black, shiny, female 22-35 mm long, 8-12 mm wide; The male is 20 29 mm long and 7 10 mm wide. The head is slightly smaller than the anterior thorax, with a longitudinal groove from the back of the head through the top of the head to the base of the labial, with the top of the head being the most distinct. The antennae are whip-shaped, grayish-blue at the base of each segment from the third segment onwards.

The antennae of the female are about twice the length of the body, and the last segment ends in grayish-white. The antennae of the male are about times the length of the body, and the last segment is black at the end. There is one spiny protrusion on each side of the prothorax, and about 20 markings composed of white hairs of different sizes on each elytra.

The base of the elytra is smooth and free of small protrusions. The ventral surface of the body is densely covered with blue-gray hairs. There are blue-gray villi on the legs, middle tibia, and dorsal surface of the tarsal joints.

Ovum. Creamy white, oblong, millimeters long, slightly curved at the ends, will turn yellow when incubated.

Larvae. The hatchling larvae are milky white, pale red after feeding, and have a brown head. The mature larvae have a yellow body, a body length of about 50 mm, a head width of about 5 mm, and a brown head. The prothorax is large and long, and the posterior half of its dorsal plate is deep and convex.

Chrysalis. Creamy white to yellowish-white overall, body length 30-37 mm; It is about 11 mm wide and the appendages are lighter in color. The anterior ends of the antennae are curled in a ring and placed on the forefoot, midfoot and wings.

Biological characteristics].

1 year 1 generation or 2 years 1 generation. Eggs, larvae, and pupae can overwinter. Adults begin to emerge in May, and their peak emergences are in early July.

Adults are active during the day, feed on petioles, leaves and branchlet cortex such as poplar and willow when supplementing nutrition, and mate 2 or 3 days after supplementing nutrition, adults carry out multiple copulation and multiple ovipositions throughout their lives, first bite 1 oval groove with the upper jaw, and then insert the oviposition tube into the phloem and xylem to lay eggs, lay 1 egg per groove, and secrete mucus to seal the oviposition hole after oviposition; For every 1 egg laid, about 1 cm2 of the phloem is necrotic on the dry skin. Each female lays an average of about 32 eggs, mainly concentrated in the trunk branches or the part of the budding branches. Adults are not strong in flying, easy to catch, and have no phototaxis habits.

Female lifespan 14-66 days; Male worms 3 to 50 days. The egg stage is 11 days. After hatching, the larvae begin to feed on the decayed phloem and excrete brown droppings.

The 2nd instar larvae begin to feed on healthy bark and xylem sideways, and expel brown droppings and debris from the oviposition holes. At the end of the 3rd or 4th instar, the larvae begin to enter the xylem and excrete white sawdust. At first the tunnel bends slightly laterally, then turns upward.

Generally, the xylem tunnel is only a habitat, and the larvae often return to feed between the phloem and the xylem, and the feces are immediately discharged from the tunnel, so the damaged trunk and bark fall in a palm-like manner. In Hebei Province, the final survival rate for its 1st generation is about: Due to the concentrated distribution of insect tracts, the trunk is often partially hollow, and the outside is swollen to form a "worm blister" with a length of 30 to 70 cm.

Spotted woodpecker and velvet beetle are its natural enemies, which have a good effect on controlling the occurrence and damage of the longhorn beetle.

The main difference is not: if you look at the elytra of an adult worm, if there are particles at the top of the elytra, it is the star beetle, and if there is no one, it is the bare-shouldered star beetle.

It can harm a variety of broad-leaved trees, such as the bare-shouldered star beetle, which mainly eats poplar, willow, elm, maple, etc.

The larvae of the longhorn beetle have no way to distinguish between male and female.

Adults can be divided into male and female.

The longhorn beetle, a general term for insects of the multiphagous suborder longhorn beetle, has chewing mouthparts and has long antennae, often exceeding the length of the body. Its larvae live in wood and can be harmful to trees or buildings.

The longhorn beetle is a herbivorous insect, which will harm woody plants, most of the pine, cypress, willow, elm, walnut, citrus, apple, peach and tea, etc., some cotton, wheat, corn, sorghum, sugarcane and hemp, etc., a few wood, buildings, houses and furniture, etc., are the main pests on forestry production, crop cultivation and building wood.

The longhorn beetle generally overwinters in the trunk of a tree as a larvae or adult. After the adult worm emerges, some need to supplement nutrition, eating pollen, young branches, young leaves, bark, sap or fruits, fungi, etc., and some do not need to supplement nutrition. The lifespan of adults is generally more than 10 days to 1 to 2 months; However, adults overwinter in the pupal chamber for up to 7 to 8 months, and males have a shorter lifespan than females.

The activity time of adults is related to the thickness and thinness of the small eye surface of the compound eye, which is generally thick, mostly active at night, and has phototaxis; Small eyes and thin faces, mostly live during the day.

Move. The oviposition mode of adult worms is related to the form of mouthparts, and generally the adult of the anterior mouth type lays eggs directly into the rough bark or cracks when laying eggs; The adult worm with a lower mouth first bites into a groove on the trunk of the tree and lays its eggs in the groove. The longhorn beetle mainly feeds on larvae, lives the longest, and causes the most serious damage to the trunk.

When the eggs hatch out of the larvae, the first instar larvae are bored into the trunk of the tree, initially feed under the bark, and after the inage increases, they burrow into the xylem for damage, and some species only stay under the bark to live, not into the xylem. The larvae move within the trunk of the tree, and the shape and length of the moth-eating tunnels vary from species to species. The larvae feed on the trunk or branches, opening their mouths into the bark at a certain distance as vents, pushing out excrement and wood chips.

When the larvae reach maturity, they form a wide pupal chamber, which is clogged with fibers and sawdust at both ends, and pupates in it. The pupal stage is about 10 to more than 20 days.

The larvae of the longhorn beetle eat the trunk and branches, affecting the growth and development of the tree, weakening the tree, leading to the invasion of germs, and it is also easy to be broken by the wind. When the damage is severe, the whole plant dies, the wood is bored, and the process value is lost. The longhorn beetle is mainly a pest of woody plants, eating away at tree trunks, branches and roots during the larval stage.

Some of them are harmful herbaceous plants, and the larvae live in the stems or roots, such as chrysanthemum beetle, melon vine beetle, etc. Some species, such as the cotton capsule, are harmful to the cotton capsule. There are also a few species where the larvae do not live in plant tissues, but feed on roots in the soil, such as the big tooth and the curved tooth saw longhorn, the grass longhorn and so on.

Chemical control of longhorn beetle.

It can be sprayed or painted with dichlorvos, phosphine, dimethoate, insecticidal pine, phosphophophosate, insecticidal net, pastrocarb, dimethoate, fluoroacetamide, etc. In Henan, Hunan, Sichuan (Chongqing) and other places in the prevention and control of pesticides such as Shuangtiao Fir Longhorn, Bare-shouldered Xingtianniu, Xingtianniu, etc., it has been proved that 40% dimethoate emulsion is sprayed 300 to 500 times, which has a good control effect.

Places of discovery: Xi'an, Shanghai.

Name: Bare-shouldered Star Celestial Bull.

Category: Arthropoda, Insecta, Coleoptera, Longhornidae.

Introduction: The body color is pitch-black with luster (similar to the Star Bull, which is easy to be misidentified.) The difference is that the star beetle has no luster, there are small black particles on the back), the body length is 2, the width is 7 12 mm, 6 legs, the antennae are 11 black and white, the base is blue-black, and the two pairs of covered wings each have a dozen white spots.

There is a spiny-like protrusion on each side, and the ability to fly is not strong.

Reproduction: Oviparous, one-year-one-generation, or two-year generation. Eggs are laid in mid-June and August, and the egg period is about 16 days, and the eggs and larvae can overwinter. Early May Late June, the larvae pupate and take about 41 days from pupae to adults.

When laying eggs, a small trough is first gnawed into the bark, and then an oviposition hole is gnawed in the trough, and each trough lays one egg (there are also two), usually about 30 eggs.

What to eat: The larvae first gnaw between the bark and the xylem, and after 25 to 30 days they begin to bury into the xylem and feed upwards, and the insect passage is generally 9 15 cm long. After the larvae have eaten into the xylem, they will often go to the outside of the xylem to feed.

Adults eat leaves or twigs, bark, and xylem. (Forestry pests, gradually kill trees over 3-5 years).

The larvae of the star beetle damage the base of the trunk and taproot, its host range is wide, the feeding is miscellaneous, the destructive is large, the control is difficult, seriously affects the growth and development of the tree, the interesting thing is that the bare-shouldered star beetle and the star beetle are very similar, the two are sometimes difficult to distinguish from each other from the appearance, this issue will talk about the difference between the star-shouldered star-longhorn and the bare-shouldered star-longhorn beetle!

Differences in morphological characteristics:

The body length of the star beetle is about 4 centimeters, the body is strong and black and shiny, and there are white spots on the wing sheath, which is very eye-catching. The difference with the bare-shouldered star longhorn is that there are small black particles at the base of the elytra, while the base of the elytra is smooth and hungry. The antennae are filamentous, black and white, about 10 cm long.

Occurrence rules: 1. Star beetle: 1 generation occurs a year, and the larvae overwinter in the cavity of trees.

In March of the following year, when the temperature rises, the overwintering larvae begin to move, and pupate in April, and the pupal period is about 25 days. Adults begin to emerge in May and can be seen in October.

2. Bare-shouldered star beetle: 1 generation occurs a year, a few 2 years 1 generation, with eggs and larvae overwintering in the bark and branches, and the pit begins to be damaged in April of the following year, and the pit is moth-shaped and U-shaped. Adults begin to appear in mid-June, and adults begin to bloom in July, and overwinter begins in October.

Control measures: 1. Suitable trees in the right place, build mixed forests, and select resistant tree species and resistant strains; The trunk is scraped and painted white;

2. Use Qilin ** root boring to control larvae; Use Qilin Guangzheng spray to control adult insect damage.

Adults: 17-39 mm long, pitch-black, with a coppery sheen. The dorsal plate of the prothorax is wrinkled and notched, with a spinous protrusion on each side. There are more than a dozen white markings on the wing sheath, and the base is smooth and free of nodulous granules.

Eggs: millimeters long, oblong-elliptic, slightly curved, milky-white; The eggs seen under the bark are mostly light yellow-brown, slightly flattened, and nearly cucumber seed-shaped.

Larvae: body length 50-60 mm, milky white, footless, with convex streaks on the dorsal plate of the prothorax.

Pupa: body length 30 mm, naked pupa, yellowish-white.

One generation occurs in one year, or one generation occurs in two years. Overwinters with larvae or eggs. When the temperature rises above 10 in April, the overwintering larvae begin to take action.

The larval pupation period is from early May to late June. It takes about 41 days from pupae to adulthood. Adults begin to appear in early June, and peak from late June to late July, with adult activity until October.

Adults begin to lay eggs in mid-June, and the peak oviposition period is between July and August, and the egg period is about 16 days. Larvae begin to appear at the end of June, and by November the temperature drops below 6 and overwintering begins. The bare-shouldered star longhorn beetle is mainly harmful to poplar, poplar, poplar, willow and weeping willow and other trees.

The larvae eat the trunk of the tree, which reduces the quality of the wood in order to cause light damage, and can cause the tree to wither and break by the wind in severe cases; Adults bite the bark and xylem of leaves or small branches, and their flight is not strong, and they mostly mate on the trunk during the day. Before the female worm lays eggs, the bark gnaws a small groove, chises an oviposition hole in the Kai, and then lays an egg (there are also two eggs) in each trough, and a female adult generally lays about 30 eggs. The grooved parts are mostly on the trunk of the tree with a thickness of 3 6 cm, especially the lateral branches are concentrated, and the parts with a lot of weight are the most, and the larger the tree, the higher the grooved parts.

The hatching larvae feed between the bark and the xylem first, and after 25 to 30 days, they begin to bury the xylem; and moths upwards. The tunnels are generally 90 mm long and the longest is up to 150 mm. After the larvae have eaten into the xylem, they often return to the outer edge of the xylem to feed on sapwood and bast.