News » Environment

The Green Lacewing

Garden friend and aphid destroyer

by

comment

By Pina Belperio,

Whistler Naturalists

Here in Whistler, we are blessed with an abundance of wildlife, plants and geological features. Sometimes, we overlook the smaller, microscopic residents of our valley. Living amongst us is one of nature’s greatest insect predators, the Green Lacewing.

If you’re a gardener, you may already be acquainted with this interesting creature. The unpleasant smelling Green Lacewing ( Chrysoperla rufilabris ) lives in our coniferous forests and valleys, controlling destructive plant pests.

I first discovered the Green Lacewing buzzing around my kitchen one summer night. It was difficult to miss the Green Lacewing with its distinct bright green body, copper-coloured eyes, and large, veined wings about half an inch in length with long, slender antennae. This slow-flying nocturnal insect feeds primarily on nectar and pollen. However, its carnivorous larvae are fiercely predatory, with a ferocious appetite for aphids, mealybugs, spider mites and other garden pests.

The larvae of the Green Lacewing – which are appropriately named aphid lions – resemble tiny alligators with their large, sucking jaws and insect-paralyzing venom. The larvae eat most soft-bodied pests and can consume over 200 aphids per week. That explains why the larvae are loved by gardeners and farmers alike.

The mating ritual of the Green Lacewing is also inimitable. The male lacewing produces mating songs by vibrating his belly rapidly, so that the tremulations are transmitted down his legs to the leaf where the female is standing. The female answers back in a similar fashion, until the pair gravitates towards one another. The female proceeds to kiss the male lacewing, followed by the two insects positioning themselves so that they hang down by their forelegs, before the mating ritual begins.

Interestingly enough, the green lacewing has evolved defense mechanisms which allow it to detect sound waves produced by bats, one of their main predators. These built-in earlike structures are located in the veins of the green lacewings’ wings, allowing it to detect the sonic sound of bats. Each time the lacewing "hears" these particular frequencies, it takes action. Some insects even change their flight patterns or exhibit erratic flight, while other lacewings fly closer to the ground to avoid detection.

The egg laying process of the female lacewing is also distinct. The mated female lays her eggs (singly) at the top of a thin hair-like stalk attached to a leaf or a piece of wood. Each egg is held away from the leaf surface by a stalk to prevent the young larvae from eating each other after they hatch.

After hatching, the green lacewing usually lives for only 20 to 40 days, but it certainly keeps itself busy during its relatively short lifespan.

So next time you notice a bright green bug flying around your house, make sure it gets the respect it deserves!

Upcoming Events:

Monthly Bird Walk — The next bird walk will take place Saturday, Oct. 2. Join Whistler experts in the monthly update of our feathered locals and migrants. For details, contact Michael Thompson at 604-932-5010.

Calling all Aspiring Nature Writers and Photographers — Have an interest in natural history? Want to educate others about your favourite flora and/or fauna? Write your very own Naturespeak article or send us your photos to accompany our articles. For more information contact Sorcha Masterson at 604-932-5089 or sorc_m@hotmail.com

Add a comment