Lacewings adults are delicate wee fairy-folk of the vegetable garden… but do not let them fool you as they are voracious hunters of pest insects and their larvae are known as ‘aphid lions’ with the looks to match!
Lacewings belong to the Neuroptera family of insects – they are not flies, in fact they are more closely related to beetles than flies (Ref 1). The order as a whole is very distinct in both their adult and larval appearance. Adults have elongated bodies reminiscent of dragonflies, but with transparent veined wings held in a dome above the body and iridescent eyes. Larvae have different body shapes and are similar in appearance to ladybug larvae but have very large mandibles. Several families are found within the order, but most of the pest controllers are located within the Chrysopidae family.
As with many other pest predators; they will be attracted to areas with lots of prey species. Those most commonly found in gardens are the most widespread throughout South Africa. They are attracted to lights and thus you might find them inside the house – scoop them up and release back to the garden!
The 3 common species to look out for are:
1. Green lacewing: Chrysoperla species are green with a ~3 cm body and their wings have no markings. Found throughout South Africa.
2. Yellow lacewing: Ceratochrysa antica are yellow and slightly larger than the green lacewing. Wings also have no markings. Likely to be found in Gauteng, KwaZulu-Natal, Mpumalanga, Limpopo and the eastern parts of the North West province.
3. Grey lacewing: Chrysemosa jeanneli are smaller than the green lacewings with grey bodies and grey wings. They have a distinctive black spot on the mid hind margin of their wings, which meet up when their wings are at rest. Found throughout South Africa.
In the family Chrysopidae, adults and larvae are mostly predatory and will feed on aphids and other soft-bodies homopterans (aphids, mites, scale, leafhoppers and mealy bugs). Adults from the grey lacewings are suspected to be pollen and nectar feeding (and hence might help out with pollination when feeding). Lacewing larvae are known as ‘aphid lions’ or ‘aphid wolves’ as they are able to devour up to 100 aphids a week! Grey lacewing larvae also display a type of camouflage behaviour by carrying devoured prey carcasses on their backs! [See Picture Here].
Lacewings: Mantidflies and Antlions
The order of Neuroptera have additional members outside of the agricultural pest control familes with some of the most interesting morphologies and lifecycles. These include the Mantidflies or mantispids (Mantispidae), which resemble miniature mantid-wasps! Adults use their raptorial forelimbs to grasp prey just like mantids. Mantidfly larvae feed on young spiders or spider eggs and pupate inside the egg sacs.
Antlions are the largest family of lacewings, best known for their whirl sand burrows wherein they catch unsuspecting ants. The larvae sit at the bottom of the funnel pit and when an ant happens to fall in it is unlikely to escape before the antlion snatches it up with its mandibles – although some jumping behaviour has been observed by would-be victims with various results. Antlion adults are large, lazy fliers. Some have spotted wings and/or resemble damselflies.