Common Green Lacewing

Learn more about Lacewings

Chrysoperla 
(Neuroptera: Chrysoperla)

Lacewings in Agriculture

The common green lacewing, C. carnea, and the red-lipped green lacewing, C. rufilabris, are species of lacewings in the genus Chrysoperla and family Chrysopidae, in the order Neuroptera with over 6000 described species (Grimaldi and Engel 2005). Lacewings are holometabolous insects preying upon many soft-bodied insect species including several species of aphids, spider mites (especially red mites), thrips, whiteflies, eggs of leafhoppers, moths, and leafminers, small caterpillars, beetle larvae, and the tobacco budworm. In field studies, C. carnea was also found to control populations of citrus thrips, Scirtothrips citri (Khan and Morse 1999a, Tauber and Tauber 1993), leafhoppers, Erythroneura variabillis (Daane et al. 1996), and tobacco budworms, Heliothis virescens (Ridgway and Jones 1968). It is for  this reason that lacewing species are found in many horticultural and agricultural cropping systems, including vegetables, fruits, nuts, fiber and forage crops, ornamentals, greenhouse crops, and forests (Ridgway and Kinzer 1974, Ridgway and Murphy 1984, Amarasekare and Shearer 2013).

Another study investigated the prey preference of third instar green lacewing, C. carnea, between western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and lettuce aphids, Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae) in laboratory experiments. Third instar C. carnea larvae readily preyed upon both thrips and aphids, with thrips mortality varying between 40 and 90%, and aphid mortality between 52 and 98%. The results of this study  indicated that C. carnea overall preferred feeding on aphids (Shrestha and Enkegaard 2013). The major predatory impact of green lacewings occurs during their predatory, polyphagous larval stage, as most adult chrysopids are free living and feed on honeydew and pollen. Due to its widespread success as a natural enemy, C. carnea (Stephens), has frequently been used as a model insect for understanding beneficial arthropods (Henry et al. 2001, Amarasekare and Shearer 2013), for this reason C. carnea has also been mass-reared and released in croplands all over the world (Henry et al. 2001, Amarasekare and Shearer 2013). In addition to these details, green lacewing biology have especially attracted research interest in the past, due to the uniqueness and diversity of species. Several morphospecies of chrysopids comprise multiple reproductively isolated species, which often can be differentiated based on courtship song characteristics (Henry et al. 1993, Henry 1985, Gerth et al. 2017).

Lacewings are also considered an important predator of long-tailed mealybug in greenhouses and interior plantscapes (Gerth et al. 2017). C. carnea has been widely used for biological control of aphids and other insect pests due to its beneficial predatory habits and compatibility with selected chemical insecticides, microbial agents, and amenability for mass rearing (Pree et al. 1989, Uddin et al., 2005, Alghamdi et al. 2018). Worldwide they rank as some of the most commonly used and commercially widely available natural enemies (Tauber et al. 2000, Amarasekare and Shearer 2013). 

Lacewing appearance and Lifecycle

Adult lacewings are typically characterized by two pairs of large, extensively veined wings (Gerth et al. 2017). Adults are pale green, about 12-20 mm long, with long antennae and bright, golden eyes. They have large, transparent, pale green wings and a delicate body. Adults are active fliers, particularly during the evening and night and have a characteristic, fluttering flight. Oval shaped eggs are laid singly at the end of long silken stalks and are pale green, turning gray in several days. The larvae, which are very active, are gray or brownish and alligator-like with well-developed legs and large pincers with which they suck the body fluids from prey. Larvae grow from <1 mm to 6-8 mm. Both C. carnea and C. rufilabris overwinter as adults, usually in leaf litter at the edge of fields. During the spring and summer, females lay several hundred small (<1 mm) eggs on leaves or twigs in the vicinity of prey. Larvae emerge in 3-6 days. The larval stage has three instars and lasts two to three weeks. Mature third instars spin round, parchment-like, silken cocoons usually in hidden places on plants. Emergence of the adults occurs in 10 to 14 days. The life cycle (under 4 weeks in summer conditions) is heavily influenced by temperature. There may be two to several generations per year. C. carnea appears to have some natural tolerance to several chemical insecticides although there may be considerable variation (Pree et al. 1989). Populations tolerant of pyrethroids, organophosphates, and carbaryl have been selected in the laboratory.

Commercial availability of lacewings

Both C. carnea and C. rufilabris are available commercially, however, improved levels of lacewing predation can also be achieved through attraction and support of lacewing populations. Supporting populations of natural enemies involves maintaining diverse habitats, as well as planting varieties of flowering plants that offer essential nectar, and pollen that can frequently be critical to lacewing survival. 

Impact of broad spectrum insecticides on lacewings

Despite evidence of reduced pesticide susceptibility of at least some Chrysoperla species, the use of broad spectrum insecticides is generally not encouraged in locations with many beneficial arthropod species (Pree et al. 1989, Henn and Weinzierl 1990). In addition, the use of herbicides can reduce the floral and nectar availability. For more information about conserving natural enemies, see the Xerces Society.