What are the methods for identifying pear tree stink bugs?

(1) Pear lace bug:

① Adult: body length about 3.5 mm, flat, dark brown. Head small, wings broad, compound eyes dark black, no simple eyes. Pronotum raised, with both sides protruding in a wing-like shape, semi-transparent, and both with net-like patterns. Forewings slightly rectangular; when at rest, the markings formed by the two overlapping forewings appear like the character "x". Hindwings membranous, white and transparent. Abdomen golden yellow, with black markings on it.

② Egg: about 0.6 mm long, initially pale green when laid, semi-transparent, later turning pale yellow, oval, with one end curved.

③ Newly hatched nymph white and transparent, compound eyes red, body length about 0.7 mm, body color turning pale green after several hours. At the 2nd instar, the abdominal tergites turn black. At the 3rd instar, wing pads appear, and there are 8 pairs of spine-like projections on both sides of the abdomen. The 5th instar nymph is about 2 mm long, wing pads about 1/3 of the body, abdomen yellow-brown, body broad and flat.

(2) Pear stink bug:

① Adult: body length 12-15 mm, width 5 mm. Body flat, nearly oval, gray-brown or gray-green-brown. Head yellow-brown, with 2 brown longitudinal markings on the center of the dorsum. Antennae filiform. Near the anterior margin of the pronotum there is a "eight"-shaped black marking. Abdomen yellow, each segment with black markings and small red dots, with 3 rectangular spots in the center, and each abdominal segment with paired triangular black spots on both sides.

② Egg: pale yellow slightly tinged with green, oval, diameter 0.8 mm. Often 20-30 eggs are laid together, covered with a layer of yellowish-white or slightly purplish-red transparent gelatinous substance.

③ Nymph: similar to adult, wingless, with 5 instars in total.

(3) Brown marmorated stink bug:

① Adult: body length 15-18 mm, width 8-9 mm, body flat, slightly oval, whole body tea-brown. Head pale yellow, with 2 brown longitudinal markings in the center. Antennae with 5 segments, dark brown. Anterior margin of the pronotum with 4 yellow-brown transverse spots, base of the scutellum with 5 small yellow spots, with the spots on both sides obvious.

② Egg: short cylindrical, initially milky white, later turning dark brown, slightly oblate. Head and thorax black. Pronotum with spine-like projections on both sides, and on the dorsal surface of the abdomen, each segment margin and both sides of the central dorsal margin have 1 black spot.