Green Lacewings
Chrysopidae
predator · generalist predator · both
Last updated
Green lacewing larvae are aggressive generalist predators sometimes called "aphid lions" for their appetite. A single larva can consume over 200 aphids per week during its two- to three-week development, along with mites, scale crawlers, whiteflies, and small caterpillars. Adults are the familiar pale green insects with delicate, net-veined wings found around porch lights on summer evenings.
Several lacewing species are native to the Puget Sound region, and eggs or larvae of Chrysoperla carnea and C. rufilabris are widely available for purchase. Adults feed on nectar and pollen rather than insects, so plantings of yarrow, sweet alyssum, and other umbellifers help sustain populations between pest outbreaks. Lacewings show moderate tolerance to some insecticides but neonicotinoids remain lethal through contaminated prey.
Target Pests (51)
- Aphid
- Apple rust mite
- Balsam twig aphid
- Black cherry aphid
- Black pineleaf scale
- Blister mite
- Boxwood leafminer
- Boxwood Mite
- Boxwood psyllid
- Cottony cushion scale
- Cyclamen mite
- Dryberry mite
- Eriophyid mite
- European elm scale
- European Fruit Lecanium
- Filbert Aphid
- Fruittree leafroller
- Grape mealybug
- Hawthorn aphid
- Holly leafminer
- Leaf curl plum aphid
- Leafhopper
- Leafroller
- Lecanium scale
- Lilac leafminer
- Linden aphid
- Madrone Leafminer
- Pear psylla
- Pear rust mite
- Pearleaf blister mite
- Pine bark adelgid
- Poplar Petiole Gall Aphids
- Prunus rust mite
- Redberry mite
- Redhumped caterpillar
- Rose leafhopper
- San Jose scale
- Scale insect
- Shield Bearer
- Spider mite
- Spruce aphid
- Spruce bud scale
- Stink bug
- Sycamore scale
- Tent caterpillar
- Thrips
- Twospotted spider mite
- Walnut Aphid
- Western flower thrips
- Winter moth
- Woolly apple aphid
Quick Reference
Identification
Adult Description
Delicate, slender-bodied insects, 12-25 mm wingspan. Bright green body with large, lacy, net-veined wings held tent-like over the abdomen at rest. Golden or copper-colored eyes (hence 'golden-eyes'). Long, thread-like antennae. Adults are weak fliers, active primarily at dusk and night; attracted to lights. Brown lacewings (Hemerobiidae) are smaller (6-12 mm) and darker (WSU HortSense; UC IPM, 2024).
Larval Description
Elongated, spindle-shaped larvae with prominent sickle-shaped mandibles used to pierce and drain prey. Gray-brown with dark markings. Three pairs of well-developed legs. Some species (trash carriers) cover themselves with debris and prey remains as camouflage. Known as 'aphid lions' due to voracious feeding behavior. 6-12 mm at maturity (UC IPM, 2024).
Size Range
12-25 mm wingspan (adults); 6-12 mm (mature larvae)
Key Features
Lacy net-veined wings, bright green body, golden eyes, thread-like antennae. Larvae distinguished by sickle-shaped mandibles.
Lifecycle & Phenology
Complete metamorphosis: egg, three larval instars, pupa, adult. Females lay 100-300 eggs singly, each on a distinctive hair-like silk stalk on leaf surfaces near prey colonies. The stalk prevents sibling cannibalism among newly hatched larvae. Eggs hatch in 3-4 days. Larvae ('aphid lions') feed voraciously through three instars over 2-3 weeks. Pupation occurs in a spherical silken cocoon in bark crevices or leaf litter, lasting approximately 1 week. Adults emerge and feed on nectar, pollen, and honeydew; most Chrysoperla species adults are not predatory. Multiple overlapping generations per year. Overwintering occurs as adults in diapause or as prepupae in cocoons (UC IPM, 2024; Principi & Canard, 1984).
| Generations per Year | Multiple; continuous overlapping generations in mild PNW summers (UC IPM, 2024) |
| Overwintering Stage | adult |
| Egg Capacity | 100-300 eggs per female lifetime, depending on diet and environmental conditions (UC IPM, 2024) |
| Larval Duration | 14-21 days through three instars (UC IPM, 2024) |
| Development Duration | Approximately 30-40 days egg to adult at summer temperatures; 519 degree-days base 10.7°C for Chrysoperla comanche (UC IPM, 2024; Tauber et al., 2016) |
| Adult Lifespan | 30-90 days depending on temperature, humidity, and food quality (UC IPM, 2024) |
| Active Months | April through October |
Habitat & Conservation
Larvae require proximity to prey colonies. Adults require nectar, pollen, and honeydew for sustenance and egg maturation. Open-structured flowers with accessible nectar, particularly Apiaceae, are important adult food sources. Overwintering adults and pupae require undisturbed leaf litter, bark crevices, or hedgerow cover. Reduced pesticide exposure is essential for larval survival on treated foliage (UC IPM, 2024; Xerces Society, 2014).
Nectar & Pollen Sources
Conservation Practices
- Permanent insectary plantings with Apiaceae species providing three-season bloomTiming: Established in fall or early springAdults of most Chrysoperla species are not predatory and depend entirely on nectar, pollen, and honeydew for survival and egg maturation; floral resource availability directly limits fecundity
- Retention of bark-creviced trees, brush piles, and leaf litterTiming: Year-roundLarvae spin silken cocoons in sheltered crevices for pupation; adults aggregate in protected sites for overwintering diapause
Pesticide Sensitivity
| Product Class | Impact | Notes |
|---|---|---|
| Neonicotinoids imidacloprid, clothianidin, thiamethoxam | lethal | Systemic uptake into plant tissue lethal to larvae feeding on contaminated prey |
| Pyrethroids bifenthrin, permethrin, lambda-cyhalothrin | moderate | Chrysopidae show notable pyrethroid tolerance compared to other beneficials; some populations have developed resistance. Still harmful at field rates |
| Spinosad spinosad | moderate | First instars suffer 33% mortality at 250 ppm; second and third instars show negligible mortality. Less harmful than to most other beneficials |
| Horticultural oils mineral oil | high | 99% mortality on eggs when applied by dipping; categorized as extremely detrimental to eggs. Low residual impact on mobile larvae and adults |
| Insecticidal soaps potassium salts of fatty acids | low | Contact only; minimal residual after drying |
Commercial Availability
2-20 per square meter per release, repeated weekly until control is achieved (Cornell Biocontrol Guide)
Larval releases most effective when pest colonies are establishing; egg releases require 3-4 day lead time before hatching (UC IPM, 2024)
Larvae are highly effective localized predators but non-flying and limited in dispersal range. Multiple releases needed for area coverage. More predictable than lady beetle releases because larvae do not disperse from release site (Cornell Biocontrol Guide).
Eggs and larvae are perishable; immediate deployment recommended. Short-term refrigeration at 40-50°F possible for eggs only (commercial product literature)