Differences Between the Brown Marmorated Stink Bug and the Yellow-Spotted Stink Bug and Their Identification
The brown marmorated stink bug and the yellow-spotted stink bug both belong to the order Hemiptera, superfamily Pentatomoidea, family Pentatomidae, and both are pests that cause relatively serious damage to ornamental garden plants.
Brown marmorated stink bug
Scientific name: Halyomorpha picus
Aliases: stinkwood stink bug, stink bug, tea-colored stink bug
Host: this species has a wide diet and harms many garden plants such as black locust, elm, fig, lilac, pomegranate, paulownia, peach, and crabapple.
Damage symptoms: adults and nymphs suck the sap of tender leaves, tender stems, and fruits, and in severe cases cause leaves to turn yellow and dry, to fall early, and to weaken the tree's vigor. Damaged tender shoots stop developing, and damaged fruits fail to develop or develop poorly.
Morphological characteristics: Adult: body length 12 mm to 16 mm, width 6.5 mm to 9.0 mm. Body color and size vary greatly, pale yellow to brown, with black punctures, or with golden-green iridescent punctures, or with a slight golden-green sheen, or the entire dorsal surface golden-green. Antennae yellowish brown, with the apex of the 3rd segment, the middle of the 4th segment, and most of the 5th segment dark brown. The rostrum reaches the middle of the 1st abdominal segment. The lateral lobes of the head are level with the middle lobe, the lateral lobes are wider, and the lateral margin forms an obvious angle near the front end, bending rather abruptly. The anterior margin of the pronotum extends slightly outward, the lateral angles are rather rounded and blunt, projecting outward only a little, and the anterior lateral margin is smooth with a narrow yellowish-brown edge. The basal margin of the scutellum has 5 faint small yellow spots, of which the 2 at the basal angles are clearer. Wings smoky brown, darker at the base than at the apex, appearing dark brown, and the veins at the apex are also dark in color. The lateral connexivum is alternately yellow and black, and the ventral surface is entirely pale yellowish brown, yellowish brown, or reddish brown, with only some green punctures near the base of the antennal segments beneath the head and on the lateral areas of the thorax. The legs have rust-colored spots. The claws and the tip of the rostrum are black. Egg: about 1 mm long, short cylindrical, grayish white; egg masses contain 24 to 28 eggs, most egg masses with 28 eggs, and the eggs in a mass are arranged fairly neatly in a hexagonal pattern. Nymph: similar to the adult, small and wingless, with black spots on the dorsal surface of the abdomen.
Life habits: In North China there is 1 generation per year, overwintering as adults in grass piles, tree holes, and similar places; overwintered adults become active in May, lay eggs in June, the egg stage lasts about 7 days, and they can lay eggs 5 to 6 times. When disturbed, adults and nymphs can secrete a foul-smelling liquid to defend against enemies, which is why they are also called stink bugs.
Control methods
1. During the adult overwintering period, carry out manual collection, or clear away fallen leaves, dead branches, and weeds and burn them in a centralized manner, which can eliminate overwintering adults.
2. Remove and destroy egg masses.
3. In the early stage of nymph occurrence, promptly spray before the nymphs disperse with 6% imidacloprid emulsifiable concentrate at 3000 times to 4000 times dilution, or 50% phoxim emulsifiable oil at 800 times dilution, or 2.5% deltamethrin emulsifiable concentrate at 3000 times dilution, or 2.5% Kung Fu emulsifiable concentrate at 3000 times dilution.
Yellow-spotted stink bug
Scientific name: Erthesina fullo
Aliases: yellow-spotted stink bug, hemp stink bug
Host: white ash, elm, persimmon, silk tree, plane tree, peach, Chinese pagoda tree, black locust, paulownia, cherry blossom, crabapple, and many other garden plants.
Damage symptoms: adults and nymphs suck the sap of leaves, tender stem tips, and young fruits, affecting the normal growth of garden plants.
Morphological characteristics: Adult: body length 18 mm to 23 mm, width about 10 mm. Black, densely covered with punctures, and with fine, irregular yellow spots. Antennae black, with the base of the terminal segment, the center of the lateral connexivum of each abdominal segment, and the middle of the tibiae yellow. From the front of the head to the base of the scutellum there is 1 thin yellow longitudinal midline. Head long, the lateral lobes level with the ends of the middle lobe, the ends of the lateral lobes narrowly pointed, making the lateral margin form an angle. The rostrum is slender and reaches the middle of the 3rd abdominal segment. The anterior lateral margin of the pronotum is slightly serrated. The center of the ventral surface of the abdomen has a sunken longitudinal groove. The tibiae of the front legs are widened, slightly expanded into a leaf-like shape. Egg: oval, glossy, egg height 2.2 mm, width 1.5 mm, diameter of the false operculum 1.2 mm. Egg masses usually contain 12 eggs, arranged in four rows. Eggs are laid on the underside of host plant leaves; newly laid eggs are pale green, turning deep yellow near hatching. Nymph: newly hatched first-instar nymphs cluster around the edge of the egg mass. First-instar nymphs have many alternating yellow and black transverse stripes on the thorax and abdomen.
Life habits: In North China there is 1 generation per year, overwintering as adults in cracks in sun-facing walls, cracks in bark, and similar places; damage begins from late April to early May, egg laying begins in late May, the nymph has 5 instars, and after the end of August adults successively overwinter. Control methods: same as for the brown marmorated stink bug.