Identification and Control Measures of the Calospilos suspecta on Euonymus bungeanus

The Calospilos suspecta, commonly known as the "hanging ghost," belongs to the family Geometridae of the order Lepidoptera. The larva has only one pair of legs on the 6th abdominal segment and one pair on the terminal segment; when moving, its head and tail come together and it arches its back as it walks. Just like measuring objects with the fingers, it is also called a looper. It mainly damages boxwood, euonymus, elm, poplar, willow, and so on, and is a polyphagous pest.

I. Morphological characteristics and habits

Adult: a medium-sized moth. Wingspan 33 to 52 mm, body yellow. The mesothoracic scutum has two black spots. The abdominal pleura and terga are both yellow. The wing ground is white, densely covered with gray and yellowish-brown spots. The base of the forewing has a variegated patch of alternating yellow and brown. There is also a yellow-brown variegated patch at the tornus of both the forewing and hindwing. Several gray spots along the outer margin of the forewing are connected together. The legs are yellowish-brown, and there is a black dot on the outer side of the trochanter of the foreleg.

Egg: hemispherical, grayish-purple, 0.8 mm in diameter, with fine longitudinal striations on the surface. There is a round dot in the center.

Larva: mature larva body length 28 to 32 mm. The body is black, with 4 yellowish-white longitudinal lines on each side. The longitudinal lines near the dorsal midline and the spiracular line are more yellow, and there are white transverse stripes on the posterior segments.

Pupa: wedge-shaped, 5.5 mm long, dark brown, short and small.

In the Shenyang area, two generations occur per year, overwintering as pupae. The first-generation adults appear from mid-May to mid-June. The peak larval damage period is in early to mid-July. The second-generation adults appear from mid-July to late August. The peak larval damage period is in early to mid-September. Adults have poor flying ability and can lay eggs after mating; each female lays 30 to 350 eggs. Eggs are mostly laid on dead shoot tips or leaves, often in clusters of more than ten or several dozen arranged in a mass. The larva has 5 instars in total. It has the habit of spinning silk and hanging down to migrate. Larval morphology often varies with the season; spring and autumn larvae have alternating black and yellow stripes, while some summer larvae are yellow-gray. In late September, after the larvae mature, they often spin silk and drop to the ground or crawl back to the ground from the tree trunk. They pupate under the layer of dead branches and fallen leaves. The pupal stage lasts 10 days, while overwintering pupae last more than 250 days.

II. Control measures and methods

1. Do a good job of forecasting and forecasting the first-generation larvae from mid-June to mid-July. Once pest damage occurs, spray pesticide immediately to kill the insects.

2. 10 days after adult emergence or during the larval damage period, spray the tree canopy with 1500 times dilution of 80% dichlorvos emulsifiable concentrate, or spray 5000 times dilution of 2.5% deltamethrin. Spray 2 times in succession, with an interval of 10 days, apply pesticide in the morning and evening, and respray after rain.

3. Manual capture and killing. (1) For small trees and seedlings, shake the trunk to capture and kill the larvae and pupae that fall off. (2) Larvae mostly concentrate on the trunk to pupate, and they should be removed.

4. Protect natural enemies such as tachinid flies and ichneumon wasps.

5. In early May, early July, and early August, use light traps to kill adults.