[Harmful symptoms]
Adults and nymphs are infested with newly withdrawn shoots, and the young shoots or petioles are inserted into the young branches or petioles with a stinging suction device to suck up the sap, causing the young branches to wither and dry up.
[Prevention and control methods]
(1) Physical control: (1) In the early morning and evening on rainy and sunny days, adult insects can be killed with net pockets. (2) During the spawning period, the orchard is often checked, and the egg mass and the undiminated first-instar nymph are removed in time. (3) When the nymphs are dispersed, the plants with fruits can be inspected and the insects can be caught. (2) Biological control: protection and utilization of natural enemies, the parasitic bees commonly found in orchards are lychee egg jumping wasps, lychee eggs flat-bellied wasps, etc. (3) Chemical control: Adults and nymphs are in full bloom, spraying agents for control. The agent is selected from 90% crystalline diphthalmid 800 times liquid, 5% high-efficiency cypermethrin acetamidine microemulsion 1000-1500 times liquid or 5% acetamidine emulsion 1500-2000 times.
[Morphological characteristics]
Adults are 19.5–24 mm long and 6.5–9 mm wide; grey-brown or greyish-black-brown; female adults have wider lateral margins on both sides of the abdomen; small head, antennae of homochrome, with a total of 5 segments, with the fifth segment being the longest; nymph antennae with reddish-brown fifth segments; straight dorsal margins of the anterior thorax, with micro-teeth, blunt corners; orange-red on the outside of the posterior thoracic plate stink gland hole, with a spot of white villi on the outside of the proximal hindpodal segment; males have significantly curved, thick, and prickly, and the ventral surface of the tibia is triangular protrusion. The third segment of the abdomen can be seen with short spine-like protrusions on both sides of the web, with a tapered process in the middle; the female has a slightly thicker hindfoot leg segment, a triangular short spine on the ventral surface at the end, and a conical process on the abdomen. The eggs are lumbar drum-shaped, 2.0-2.3 mm long, about 1.7 mm wide, 8-14 grains arranged in clusters, dark black brown, slightly shiny, with white spots on it, a white band around the near bottom, an oval fossa in the center of the bottom to fix the attachment when laying eggs, dissect the female worm, there are 18 to 20 eggs in the abdomen; the false egg lid is located above one end, nearly round, and on the side of the false egg cover near the center of the egg, there is a clear curved ridge line. The nymphs are 5 years old, bright red when they hatch, the center of the posterior thorax to the end of the abdomen is black brown, and the whole of the posterior becomes black, similar to black ants; the anterior tibia of the 1st to 3rd instar nymphs strongly expands into a leaf-like shape, and the middle and posterior tibial segments are also slightly expanded; and the fourth, fifth, sixth and seventh segments of the abdominal dorsal of each age have a pair of stinky glandular foramens in the center.
[Life Habits]
Nanchang, Jiangxi, occurs 2 generations a year, with adults overwintering under dead branches and leaves near the host. The activity begins in early to mid-March of the following year, and in order to harm the newly withdrawn spring buds, it will be mated and spawned from late April to early May, until August. Continue to feed during the mating period, pierce the mouthpart into the young branch or petiole, suck the juice, and the wound becomes a water-stained black-brown color for 2-4 days, and the buds and leaves at the upper end wilt and then die. The first generation of nymphs hatch from mid-May to mid-July, the adults feather from mid-June to mid-August, and lay their eggs from late June to late August. The second generation of nymphs hatch from early July to early September, feather from early August to early October, and overwinter from mid-to-late October to mid-November. The eggs are laid on the twigs or on the back of the leaves, and the hatching nymphs lie still next to the egg shell, and soon flock to feed near the egg shell, dispersing from the second instar to feed on the young shoots with the adults. When adult insects and nymphs are alarmed, they are mostly dodging, and when they continue to disturb, they can fake death and fall on other branches or fall to the ground, or fly away elsewhere.