Hosts or Prey
Adults are soft-bodied insects with golden eyes and 4 membranous wings held rooflike over the body at rest. The wings and body are commonly green. Adults (head to wing tip, excluding antennae) average about 3/4 inch (19 mm).
Eggs are oblong and 1/16 inch (1.5 mm) or less in length. Each is laid on the end of a silken stalk attached to plants. Eggs are pale yellowish-green or white when laid, then change to bluish-green and finally gray before hatching.
Larvae are elongate and flattened with distinct legs and resemble tiny alligators. The body is about 1/2 inch long or less and commonly cream, tan, or yellowish with lengthwise lines or rows of spots that are blackish, dark or light brown, or reddish. Larvae have prominent, paired, tubelike mouthparts that curve inwards.
Pupae occur in a roundish cocoon about 1/8 to 1/4 inch (3–6 mm) in diameter. The curled body is commonly visible through the loosely woven, whitish silk.
Green lacewings (Chrysopidae) and brown lacewings (Hemerobiidae) resemble each other as adults and larvae. Among California species the adults and last instars of green lacewings average about twice the length of brown lacewings.
Adult brown and green lacewings are not reliably distinguished by color. Adults of some species of green lacewings are normally brown, grayish, or reddish, resembling coloration of most brown lacewings. Some normally green species of Chrysopidae can turn brown or reddish during late fall through early spring, such as the common Chrysoperla carnea. Whether costal crossveins are forked (Y-shaped) reliably distinguishes the adults.
In comparison with brown lacewings, larvae of green lacewings are distinguished by a trumpetlike appendage (empodium) between the pair of tarsal claws on the end of the feet. The thoracic segments of green lacewing larvae are of approximately equal length; brown lacewing larvae appear to have a prominent neck because the first abdominal segment (prothorax) is elongated in comparison with the second and third segments with legs.
Green lacewings develop though 4 stages: egg, larva, pupa, and adult. The adult female lays about 100 to 300 eggs during her several-week lifespan. After hatching, larvae develop through 3, increasingly larger instars before pupating on plant surfaces or under loose bark.
All stages can occur throughout the year in locations without cold winters. Adults become less active and may stop laying eggs and change coloration during late fall through winter. Especially in locations with cold winters, overwintering is mostly as inactive last instars (prepupae) or pupae within silken cocoons in bark crevices or other protected locations.
Green lacewings commonly have several generations per year. Egg to adult development requires about 4 to 6 weeks when temperatures are warm.
Green lacewings occur in field and tree crops, gardens and landscapes, and wildlands. Adults feed on honeydew, plant nectar, and yeasts; some additionally are predaceous (e.g., Chrysopa species) while others are not (Chrysoperla species).
Larvae use their sharp mouthparts to impale prey and suck the body contents. Larvae of certain genera (e.g., Ceraeochrysa) cover their body with plant debris or prey remains, such as the cocoons (puparia) of male scales or flocculence (waxiness) of woolly aphids. Other species only sometimes cover their body with trash, such as Chrysopa quadripunctata when preying on woolly aphids. This covering may serve as a defense against predators, such as ants that tend and protect aphids from natural enemies.
Some species of green lacewings are commercially available and sold as adults, eggs, or larvae. These sometimes are released to help control pests in greenhouses.
To increase the effectiveness of resident natural enemies and any that are released
- Avoid the use of broad-spectrum and persistent insecticides and miticides (acaricides).
- Control ants and dust.
- Grow flowering plants that provide nectar and pollen for adults (insectary plants).
At least 37 species of green lacewings in 11 genera occur in California. These include Ceraeochrysa, Chrysopa, Kymachrysa, Pseudomallada, and Yumachrysa spp. and 7 or more species each of Chrysoperla, Eremochrysa, and Meleoma.
- Biological Control and Natural Enemies of Invertebrates, UC Integrated Pest Management Program
- Chrysopidae, Wikipedia
- Family Chrysopidae - Green Lacewings, BugGuide, Iowa State University
- The Biology of Chrysopidae and Hemerobiidae (Neuroptera), with Reference to their Usage as Biocontrol Agents, Transactions of the Royal Entomological Society London
- Natural Enemies Handbook, UC Integrated Pest Management Program
- Neuroptera, Chrysopidae (Hagen 1866): Description & Statistics, UC Riverside
- Protecting Natural Enemies and Pollinators, UC Integrated Pest Management Program
- Species Catalog of the Neuroptera, Megaloptera, and Raphidioptera of America North of Mexico (PDF), California Academy of Sciences
- Phylum: Arthropoda
- Class: Insecta
- Order: Neuroptera
- Family: Chrysopidae