Pest
Guides
Homadaula
Homadaula is a genus of small moths in the family Galacticidae, established by Lower in 1907. The genus contains approximately 15 described species distributed across Africa, Asia, and Australia. Several species are known as webworms, with larvae that construct silk webs on host foliage. Homadaula anisocentra, the mimosa webworm, is the most economically significant species and has been introduced to North America as a pest of ornamental honeylocust and mimosa trees.
Homadaula anisocentra
mimosa webworm, Mimosa Webworm Moth
Homadaula anisocentra, commonly known as the mimosa webworm, is an introduced moth species in the family Galacticidae (formerly placed in Plutellidae). Native to China, it was accidentally introduced to the United States in the 1940s and has become a significant pest of ornamental trees. The species primarily attacks mimosa (Albizia julibrissin) and honeylocust (Gleditsia triacanthos), where larvae construct silk webbing to feed on leaves. It completes two generations annually in the Mid-Atlantic region, with an additional third generation in southern states.
Homalodisca vitripennis
Glassy-winged Sharpshooter
Homalodisca vitripennis, commonly known as the glassy-winged sharpshooter, is a large leafhopper native to the southeastern United States and northeastern Mexico. It has become a major invasive pest in California, Hawaii, and the Pacific Islands, where it vectors Xylella fastidiosa, the bacterium causing Pierce's disease of grapevine—a lethal condition for vineyards. The species exhibits complex vibrational communication during mating, with males and females engaging in duets using species-specific signals. Populations in California's Central Valley have developed significant resistance to neonicotinoid insecticides, particularly imidacloprid, creating challenges for chemical management. Classical biological control using egg parasitoids from the genus Gonatocerus (family Mymaridae) has proven effective, with parasitism rates reaching 80-100% in some areas.
Homoeosoma electellum
American sunflower moth, sunflower moth, head moth
Homoeosoma electellum, commonly called the American sunflower moth or sunflower moth, is a small pyralid moth native to North America and also present in South America. It is the most economically significant pest of cultivated sunflowers in major production regions including Texas, Nebraska, California, and the Canadian Prairie Provinces. The species does not overwinter in Canada; adults migrate northward annually from southern populations. Females are strongly attracted to blooming sunflower heads, where they deposit eggs on or near the florets.
Hoplocampa
fruit sawflies, apple sawflies, plum sawflies
Hoplocampa is a genus of sawflies in the family Tenthredinidae, comprising approximately 20 described species distributed primarily across the West Palaearctic. The genus includes several economically significant pests of fruit trees, notably Hoplocampa testudinea (European apple sawfly) and H. flava (plum sawfly). Females oviposit into flowers, and larvae develop within developing fruitlets, causing characteristic damage. Many species reproduce parthenogenetically.
Hoplocampa testudinea
apple sawfly, European apple sawfly
Hoplocampa testudinea is a sawfly species in the family Tenthredinidae that is a significant pest of apple orchards. Native to Europe, it was accidentally introduced to North America in 1939 and has since become invasive across the northeastern United States and Canada. The larvae develop inside developing apple fruitlets, causing characteristic ribbon scars or fruit drop, while adults are active during apple bloom and oviposit into the calyx of flowers.
Hyadaphis foeniculi
Fennel Aphid
Hyadaphis foeniculi is a cosmopolitan aphid species and major pest of fennel (Foeniculum vulgare), native to Mediterranean regions and introduced to Brazil and other areas. Laboratory studies demonstrate strict thermal requirements: nymph development occurs only between 15-30°C, with 3°C and 33°C lethal. The species exhibits four nymphal instars with temperature-dependent development rates, completing the nymphal stage in 5 days at 30°C to 19 days at 15°C. Winged adults reproduce parthenogenetically, forming colonies inside fennel flowers during hot periods. The aphid vectors at least 12 plant viruses and produces honeydew that facilitates sooty mold growth, compounding crop damage.
Hyalopterus
Mealy Plum-Reed Aphids
Hyalopterus is a genus of aphids in the family Aphididae, commonly known as mealy plum-reed aphids. Species in this genus are cosmopolitan pests of stone fruit trees in the genus Prunus, causing damage through direct feeding and virus transmission. The genus has undergone recent taxonomic revision, with molecular and morphometric analyses supporting at least three distinct species: H. pruni, H. amygdali, and H. persikonus (the latter described in 2006). Species boundaries are strongly correlated with host-plant associations.
Hyalopterus pruni
Mealy Plum Aphid
Hyalopterus pruni, the mealy plum aphid, is a sap-feeding aphid in the family Aphididae with a cosmopolitan distribution. It exhibits a complex life cycle involving multiple generations of wingless adults followed by the production of winged migrants that disperse to secondary hosts. The species is notable for its waxy covering and seasonal host alternation between Prunus species and grasses or reeds.
Hyblaea puera
teak defoliator
A small moth (wingspan 3–4 cm) and major defoliator of teak and mangrove ecosystems across tropical Asia. Adults have greyish-brown forewings that conceal brightly colored black and orange-yellow hindwings at rest. The species undergoes dramatic population outbreaks, with densities shifting from endemic levels to epidemic proportions seasonally. It has expanded beyond its native South and Southeast Asian range to Central America, Africa, and Australia, and has recently emerged as a serious invasive pest of mangroves in India and China.
Hybomitra affinis
moose-fly
A horse fly species in the family Tabanidae, commonly known as the moose-fly. Females bite while males do not. It is among the most abundant and widely distributed Tabanidae species in Canada, occurring in woodland habitats where it serves as an important pest of humans and other mammals.
Hybomitra frontalis
horse fly
Hybomitra frontalis is a Nearctic horse fly species in the family Tabanidae. It is among the most widely distributed, abundant, and troublesome biters of animals and humans in North America. The species exhibits extreme variation in color and size across its range, particularly in Canadian populations from Nova Scotia, Labrador, and central Manitoba. Taxonomic relationships within the H. frontalis complex have been debated for over a century, with five nominal species described from regional populations.
Hylesinus
crenulate bark beetles
Hylesinus is a genus of bark beetles in the family Curculionidae comprising more than 180 described species. Members are commonly known as crenulate bark beetles and are primarily associated with woody plants, particularly ash (Fraxinus) and pistachio (Pistacia). Several species have been studied as pests of economic or ornamental importance.
Hylobiini
Hylobiini is a tribe of weevils within the subfamily Molytinae (Curculionidae). The tribe includes approximately 89 species in the genus Heilipus, which are distributed across the Americas. Members of this tribe are primarily associated with the plant family Lauraceae, with some species functioning as seed predators in fruits and others as bark-boring pests. The tribe contains three subtribes: Epistrophina, Hylobiina, and Incertae sedis.
Hylobius warreni
Warren's rootcollar weevil, Warren rootcollar weevil
Hylobius warreni is a flightless weevil native to boreal forests of Canada, where it is a significant pest of coniferous trees. Adults feed on bark of spruce, pine, and other conifers before oviposition, while larvae tunnel in the root collar region, often girdling and killing young trees. The species has emerged as a particular concern in areas affected by mountain pine beetle outbreaks due to increased reforestation efforts. Population levels are influenced by stand density, tree age, and depth of duff material around tree bases.
Hylotrupes
House Longhorns, House Longhorn Beetle, Old House Borer, European House Borer, Italian Beetle
Hylotrupes is a monotypic genus of woodboring beetles in the family Cerambycidae, containing only the species Hylotrupes bajulus. The genus is the sole member of the tribe Hylotrupini. The species has been introduced globally through timber trade and is recognized as a significant pest of structural softwood timber. Adults are active in summer months, while larvae develop slowly within wood.
Hyperinae
Cocoon Weevils
Hyperinae is a subfamily of true weevils (Curculionidae) whose larvae are notable for constructing silk cocoons for pupation, earning them the common name 'Cocoon Weevils.' Larvae of some species exhibit unusual social behaviors, including coordinated processionary movement and chemical trail-following—traits convergent with social caterpillars but rare among beetles. The subfamily's taxonomic placement has been debated, with some species historically classified under Molytinae. Host plant associations include Malvaceae and Ericaceae, with the latter representing a newly documented host family for the group.
Hyperomyzus lactucae
Sowthistle Aphid, Blackcurrant-sowthistle Aphid
Hyperomyzus lactucae is a European aphid species in the family Aphididae, commonly known as the sowthistle aphid or blackcurrant-sowthistle aphid. The species exhibits a host-alternating life cycle, utilizing Sonchus species (sowthistles) as primary hosts and Ribes nigrum (blackcurrant) as a secondary host. It is a known vector of lettuce necrotic yellows virus and has been introduced to Australia as a pest of lettuce crops. Development, survival, and reproduction are strongly influenced by temperature and photoperiod, with faster development at higher temperatures within a range of approximately 12.5–24°C.
Hypsipyla grandella
Mahogany Shoot Borer
Hypsipyla grandella is a pyralid moth whose larvae are serious pests of mahogany (Swietenia spp.) and Spanish-cedar (Cedrela spp.). The larvae bore into terminal shoots and seeds, causing significant damage to plantation forestry in the Neotropics. Adults have silvery hyaline hindwings that distinguish them from the congeneric Hypsipyla ferrealis, which has gray hindwings. The species has been introduced to Mauritius outside its native range.
Icerya purchasi
cottony cushion scale, fluted scale, cochinilla australiana
Icerya purchasi is a scale insect native to Australia that has become a globally distributed pest of citrus and ornamental plants. The species is notable for its distinctive reproductive system: most individuals are hermaphrodites capable of self-fertilization, with rare males enabling occasional outbreeding. Adult females are sessile and produce large white fluted egg sacs that can exceed twice the body length. The species achieved historical significance as the target of one of the first successful biological control programs, using the vedalia beetle (Novius cardinalis) in California in 1888–1889.
Illinoia liriodendri
tuliptree aphid, tulip tree aphid
Illinoia liriodendri is a sap-feeding aphid native to eastern North America that specializes on tuliptree (Liriodendron tulipifera). It has become an invasive pest in Europe, where it was first recorded in the early 2000s and has since spread to multiple countries. The species exhibits a monoecic-holocyclic life cycle, with peak populations occurring in late spring. It is considered the most significant insect pest of tuliptree in urban landscapes, capable of reaching high densities that produce substantial honeydew and impact young trees.
Illinoia rubicola
Spot-winged Raspberry Aphid
Illinoia rubicola is an aphid species in the family Aphididae, commonly known as the Spot-winged Raspberry Aphid. The species was described by Oestlund in 1886. It is placed in the genus Illinoia, tribe Macrosiphini, and is associated with raspberry (Rubus) host plants. Taxonomic status varies between sources, with Catalogue of Life listing it as a synonym while GBIF and iNaturalist treat it as accepted.
Illinoia spiraecola
spirea aphid, green citrus aphid
Illinoia spiraecola is a medium-sized aphid species in the family Aphididae. It is primarily associated with Spiraea (spirea) as a host plant and has been documented as a pest of citrus in some regions. The species exhibits the typical aphid life cycle with both sexual and parthenogenetic generations, and produces alate (winged) dispersal morphs.
Incisitermes snyderi
Southeastern Drywood Termite
A drywood termite species in the family Kalotermitidae, found in the southeastern United States. Colonies are small to moderate in size and live entirely within wood without soil contact. The species is a significant pest of structural timber and wooden objects in its range.
Insecta
Insects
Insects constitute the largest and most diverse class of arthropods, comprising more than one million described species with estimates of total species ranging from 2 to 30 million. They are characterized by a three-part body plan (head, thorax, abdomen), three pairs of jointed legs, compound eyes, and one pair of antennae. Insects occupy virtually every terrestrial and freshwater habitat, and many have colonized marine environments. Their ecological dominance stems from extraordinary diversity in form, function, and life history strategies.
Klambothrips
Klambothrips is a genus of thrips in the family Phlaeothripidae, established by Mound and Morris in 2007. The genus includes at least one notable invasive species, Klambothrips myopori, which has been extensively studied in California. This species is a specialist herbivore on plants in the genus Myoporum and has become a significant pest of ornamental plantings in urban landscapes.
Klambothrips myopori
Naio Thrips
Klambothrips myopori is a gall-forming thrips in the family Phlaeothripidae, described by Mound and Morris in 2007. Native to Australia and New Zealand, it invaded California in 2005 and has since become established in Hawaii and the contiguous United States. The species is obligately associated with Myoporum host plants, inducing galls on foliage. It has emerged as a significant pest of ornamental plantings in California, with documented variation in host plant suitability across different Myoporum cultivars.
Labops
grass bugs, black grass bugs
Labops is a genus of plant bugs in the family Miridae containing approximately 13 described species. Species within this genus are commonly known as grass bugs or black grass bugs and are associated with grassland habitats. Labops hesperius, the most studied species, is a significant pest of rangeland grasses in western North America. The genus is characterized by its association with Poaceae hosts and its economic impact on seed production in range and forage grasses.
Lagocheirus araneiformis
Spider Longhorned Beetle, Cassava Borer, Almácigo Borer
Lagocheirus araneiformis is a longhorn beetle in the subfamily Lamiinae, described by Linnaeus in 1767. It reaches 20–28 mm in length with grey-brown coloration. The species is widely distributed across the Americas and has been recorded as a pest of cassava and sugarcane. Multiple subspecies have been described from Caribbean islands and other regions.
Lampronia
currant moths, shoot borers
Lampronia is a genus of small moths in the family Prodoxidae with a Holarctic distribution. The genus contains approximately 25 described species, with additional undescribed species in North America, Japan, and Iran. Several species are economically significant pests of cultivated currants (Ribes spp.), particularly in northern Europe. Most species are diurnal in habit.
Laniifera cyclades
Cactus Moth, Prickly Pear Moth
Laniifera cyclades is a snout moth in the family Crambidae and the sole member of its genus. It is native to Mexico and the southwestern United States. The species is notable for its specialized diet on prickly pear cactuses (Opuntia), which has led to its introduction as a biological control agent in regions where these cactuses are invasive. Adults are active from July to September and have a wingspan of approximately 40 mm.
Lauritrioza
bay sucker
Lauritrioza is a monotypic genus of psyllids (Hemiptera: Triozidae) containing the single species L. alacris. The genus is defined by its obligate association with Laurus species, on which it induces distinctive leaf-edge galls. Adults and nymphs inhabit these galls, with nymphs producing white waxy secretions. The genus has expanded from its native European range through human-mediated introduction to western North America, Brazil, and Jordan.
Lepidosaphes ulmi
oystershell scale, apple mussel scale
Lepidosaphes ulmi, commonly known as the oystershell scale or apple mussel scale, is a widely distributed armored scale insect in the family Diaspididae. It is a significant pest of deciduous trees and woody plants, including major fruit crops such as apples, pears, plums, and peaches. The species causes damage by attaching to bark and sucking sap, potentially killing branches or entire trees under heavy infestation. It has been introduced to many regions worldwide beyond its native range and is considered invasive in numerous countries.
Leptoglossus occidentalis
Western Conifer Seed Bug, WCSB
Leptoglossus occidentalis, commonly known as the Western Conifer Seed Bug, is a leaf-footed bug native to western North America that has undergone dramatic range expansion. Originally confined to the Pacific coast region from California to British Columbia, it began spreading eastward in the 1950s, reaching the Atlantic coast by the 1990s. The species has also become invasive in Europe (first detected in Italy in 1999), Asia, South America, and elsewhere. Adults are notable for their loud, droning flight and tendency to seek shelter indoors during autumn, where they become nuisance pests. They feed on conifer seeds and developing cones, particularly of pines, and can cause significant damage in seed orchards.
Leptoypha minor
Arizona ash lace bug, ash lace bug
Leptoypha minor, commonly known as the Arizona ash lace bug, is a species of lace bug in the family Tingidae. It is a documented pest of ash trees (Fraxinus spp.), causing damage to twigs and foliage. The species is particularly abundant in California and has been economically significant as an ornamental pest since its formal description in 1942.
Leptoypha mutica
Fringetree Lace Bug
Leptoypha mutica is a lace bug (family Tingidae) native to North and Central America. It is a specialist herbivore of plants in the family Oleaceae, with documented associations including ash (Fraxinus), fringetree (Chionanthus virginicus), lilac (Syringa villosa), and Chinese privet (Ligustrum sinense). The species has been studied for its developmental biology and host choice behavior, particularly on invasive Chinese privet. Its feeding causes chlorotic blotches on leaves, with damage concentrated around leaf midribs and lateral veins.
Lepyronia
spittlebugs, froghoppers
Lepyronia is a genus of froghoppers (spittlebugs) in the family Aphrophoridae, comprising approximately 17 described species distributed across the Holarctic region. Nymphs develop within protective spittle masses on host plant stems, feeding on xylem sap. The genus includes notable agricultural and forest pests, with at least one species confirmed as a vector of phytoplasma plant pathogens. Adults are active in mid-summer and are capable of jumping considerable distances.
Leucoma salicis
White Satin Moth, Satin Moth
Leucoma salicis is a medium-sized moth native to the Palearctic, introduced to North America in the 1920s where it became an invasive pest. Adults are distinguished by pure white wings with a silky sheen, held tent-like over the body, contrasting with striking black-and-white banded legs. Larvae feed on Salix and Populus species and can cause severe defoliation damage. The species is univoltine in most of its range, with adults active in June through August.
Limnoriidea
Gribbles and allies
Limnoriidea is a suborder of marine isopod crustaceans containing three families: Hadromastacidae, Keuphyliidae, and Limnoriidae. Members are commonly known as gribbles and allies. The group is distinguished by wood-boring habits in many species, particularly within Limnoriidae. They are exclusively marine and play a significant role in coastal ecosystems through wood decomposition.
Limonius brevis
Limonius brevis is a species of click beetle in the family Elateridae. The genus Limonius includes several economically important pest species known as wireworms, the soil-dwelling larval form that damages crop roots. Research on related Limonius species has investigated pheromone-based trapping methods for monitoring and management.
Limonius jonesi
Limonius jonesi is a species of click beetle (family Elateridae) described by Lane in 1965. It belongs to a genus containing several North American pest species commonly known as wireworms in their larval stage. The species is one of multiple Limonius species studied for pheromone-based trapping methods as part of integrated pest management research.
Limonius pectoralis
Limonius pectoralis is a species of click beetle (family Elateridae) described by LeConte in 1866. It is one of several Limonius species known as agricultural pests, with larvae commonly referred to as wireworms. The species has been documented across northern and western North America, including Canadian provinces from British Columbia to New Brunswick. Research has investigated pheromone-based trapping methods for this species as part of integrated pest management strategies.
Liohippelates collusor
eye gnat
Liohippelates collusor is a species of eye gnat in the family Chloropidae, recognized as a significant pest of humans and animals in the United States since the 1930s. Along with Liohippelates pusio, it has been the focus of extensive research on biology, ecology, and management. The species causes considerable discomfort and stress through persistent attraction to eyes, wounds, and body openings, and may transmit pathogens. Its biology and life cycle have been well studied in agricultural systems, though its ecological roles in natural ecosystems remain poorly documented.
Liorhyssus hyalinus
Hyaline Grass Bug
Liorhyssus hyalinus is a small scentless plant bug in the family Rhopalidae, widely distributed across multiple continents. Adults measure 6.5–7.5 mm and are active year-round in suitable climates. The species is a documented pest of quinoa cultivation in South America, particularly at lower elevations outside the crop's Andean origin, and has been recorded feeding on developing grains of maize and sorghum. Laboratory studies indicate optimal development and reproduction occur at 30°C, with five nymphal instars and thermal requirements of 68.6 degree-days for egg development and 114.8 degree-days for nymphal development.
Lipaphis pseudobrassicae
Turnip Aphid
Lipaphis pseudobrassicae, commonly known as the turnip aphid, is a Brassicaceae-specialist aphid and significant agricultural pest. It exhibits high biotic potential with rapid population growth rates on host plants. The species shows better adaptation to high temperatures than some congeners, suggesting increasing relevance in warmer growing seasons and regions. It is a target for integrated pest management strategies and biological control programs.
Liriomyza brassicae
Cabbage leafminer, Serpentine leaf miner
Liriomyza brassicae is a leaf-mining agromyzid fly whose larvae create serpentine mines within the leaves of host plants. The species is a documented pest of brassicaceous crops including cabbage, broccoli, cauliflower, and Chinese broccoli. It has been recorded from South Florida and other regions of the United States including Vermont, Hawaii, and the conterminous 48 states.
Lissorhoptrus oryzophilus
Rice Water Weevil
Lissorhoptrus oryzophilus, the rice water weevil, is a major agricultural pest of rice and the most destructive invertebrate pest of California rice. Native to the southeastern United States, it has spread invasively to Asia since 1976 and Europe since 2004, with populations establishing in California for over 50 years. The species exhibits a unique reproductive strategy: most populations reproduce sexually, but a small percentage in the native range reproduces by triploid parthenogenesis, facilitating rapid range expansion. Adults feed on rice leaves and sheaths, while aquatic larvae feed on roots, causing yield losses up to 25-30% in severe infestations.
Listronotus oregonensis
carrot weevil
Listronotus oregonensis, the carrot weevil, is a significant agricultural pest of Apiaceae crops in North America. It was first recognized as a pest in 1902 and primarily attacks cultivated carrot, parsley, celery, and dill. Larval feeding on roots causes direct damage that can reduce yields by up to 50%. The species has low dispersal capacity, moving mainly by walking despite being winged, which makes crop rotation an effective management strategy.
Lopholeucaspis japonica
Japanese maple scale
Lopholeucaspis japonica is an invasive scale insect in the family Diaspididae, first described by Cockerell in 1897. Native to Asia, it has established populations across multiple continents including North America, Europe, and Australia. The species feeds on woody plants and has been documented on diverse hosts including crapemyrtle, pomegranate, citrus, and various ornamental shrubs. Its invasion has prompted detection efforts and biological control research, particularly regarding associated parasitoid wasps.
Lopidea major
Red Mountain laurel mirid, Scarlet Mountain Laurel Mirid
Lopidea major is a plant bug in the family Miridae, commonly known as the Red Mountain laurel mirid or Scarlet Mountain Laurel Mirid. It is a frequently-encountered pest of the Texas Mountain Laurel (Sophora secundiflora), though it causes little real damage to the host plant. The species is distributed across Central America and North America, with confirmed records from Texas and Querétaro, Mexico.