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Lacewing (beneficial insect)

Characteristics:

  • Eggs: Females lay small, elongated white eggs that are attached to foliage by a slender stalk. Eggs hatch in 5 days.
  • Larvae: Larvae are brown with yellow dots along their side and can grow up to 9 millimetres in length. Larvae look like flat alligators with large, curved, pincer-like jaws. Larvae prey on many pest insects but prefer aphids, which is why they are also known as “aphid lions”.
  • Pupae: After 12 days, larvae create a cocoon where they stay for 10 days before emerging as an adult lacewing.
  • Adults: Adult lacewings are green or yellow green insects approximately 20 millimetres in length. Adults have golden eyes and have four delicate lace-like wings which can span over 30 millimetres. If caught, lacewings emit a foul odour as a protective mechanism.

Encouraging lacewing populations:

  • Preferred food sources: Lacewing larvae are more important predators than adults; larvae can eat anywhere from 20 to a few hundred aphids per day. Larvae also eat mealy bugs, scale, spider mites, mite eggs, whiteflies, leafhoppers, small caterpillars, and thrips. Adult lacewings feed on pollen, honeydew, and mealy bugs.
  • Bright light: Bright light attracts adult lacewings. It’s the reason why they often fly towards your home’s interior lights when you open your door at night.

IPM Toolkit:

Lacewings are one of the most important ‘biological tools’ you have in your IPM toolkit. Avoid accidentally killing these beneficial insects through the use of chemical insecticides.