''Dicyphus hesperus'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

of true bug in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Miridae. It is a generalist

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill t ...

of other insects and also feeds on plant tissues. It is native to North America and has been used there in

biological control Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also i ...

of agricultural

pests PESTS was an anonymous American activist group formed in 1986 to critique racism, tokenism, and exclusion in the art world. PESTS produced newsletters, posters, and other print material highlighting examples of discrimination in gallery represent ...

, especially whitefly on tomatoes.

Ecology

''D. hesperus'' is a

and preys on other insects such as

whitefly Whiteflies are Hemipterans that typically feed on the undersides of plant leaves. They comprise the family Aleyrodidae, the only family in the superfamily Aleyrodoidea. More than 1550 species have been described. Description and taxonomy The ...

aphid Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A t ...

mite Mites are small arachnids (eight-legged arthropods). Mites span two large orders of arachnids, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari, but genetic analysis does not show clear e ...

s and

caterpillar Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder Sy ...

s. It is used in the

of insect

. However it is not entirely predatory and feeds on plant tissues also. One of its plant hosts is the common mullein (''

Verbascum thapsus ''Verbascum thapsus'', the great mullein, greater mullein or common mullein is a species of mullein native to Europe, northern Africa, and Asia, and introduced in the Americas and Australia. It is a hairy biennial plant that can grow to 2 m tal ...

''). As an

omnivore An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nu ...

, it alternates between feeding on plants and on animals, and if deprived of all suitable plant tissue, it will die, even in the presence of whiteflies.

Use in biological control

Generalist predators can be very useful for biological control in tomato crops in enclosed environments, but the introduction of non-indigenous species is risky because of the unknown ecological effects they may have if they escape into the wider environment. For this reason, native species are preferable, and ''Dicyphus hesperus'' can fulfil this role in North America in the same way that '' Macrolophus caliginosus'' is used in vegetable crops in Europe. Research has shown that ''D. hesperus'' preys on the greenhouse whitefly (''

Trialeurodes vaporariorum ''Trialeurodes vaporariorum'', commonly known as the glasshouse whitefly or greenhouse whitefly, is an insect that inhabits the world's temperate regions. Like various other whiteflies, it is a primary insect pest of many fruit, vegetable and o ...

''), and the two-spotted spider mite (''

Tetranychus urticae ''Tetranychus urticae'' (common names include red spider mite and two-spotted spider mite) is a species of plant-feeding mite generally considered to be a pest. It is the most widely known member of the family Tetranychidae or spider mites. It ...

''), both in the laboratory and in a glasshouse planted with

tomato The tomato is the edible berry of the plant ''Solanum lycopersicum'', commonly known as the tomato plant. The species originated in western South America, Mexico, and Central America. The Mexican Nahuatl word gave rise to the Spanish word ...

es. When offered both pests it preferentially selects the whitefly. The mirid bug completed its development from egg to adult on either of the two food sources, but it grew faster and was larger at maturity when feeding on the whitefly. ''D. hesperus'' has also been tested as a biological control for the western flower thrips (''

Frankliniella occidentalis The western flower thrips 'Frankliniella occidentalis'' (Pergande)is an invasive pest insect in agriculture. This species of thrips is native to the Southwestern United States but has spread to other continents, including Europe, Australia (wh ...

'') on tomatoes. It was effective at reducing the number of thrips but when the ratio of predator to prey was too high (>1:10), some damage was caused to the tomato fruits by ''D. hesperus''. ''D. hesperus'' feeds on the mullein ''Verbascum thapsus'' and to a lesser extent on the

eggplant Eggplant ( US, Canada), aubergine ( UK, Ireland) or brinjal (Indian subcontinent, Singapore, Malaysia, South Africa) is a plant species in the nightshade family Solanaceae. ''Solanum melongena'' is grown worldwide for its edible fruit. Mo ...

, and can be maintained on these plants in a greenhouse as a preventative measure. As well as controlling greenhouse whitefly and silverleaf whitefly (''

Bemisia tabaci The silverleaf whitefly (''Bemisia tabaci'', also informally referred to as the sweet potato whitefly) is one of several species of whitefly that are currently important agriculture, agricultural pest (animal), pests. A review in 2011 concluded t ...

''), it feeds on russet mites ('' Aceria anthocoptes''), predatory mites, aphids and the eggs of moths. It causes some damage to green tomato fruits in the absence of sufficient alternative plant sources of food, but does not cause sufficient harm for the ripe fruit to be down-graded. However, in gerbera crops, the nymphs and adults may feed on the developing flower buds and cause distortion and spoilage of the flowers.

References

Insects described in 1943 Dicyphini {{miridae-stub