Willow
Guides
Agrilus politus
willow gall limb borer, common willow agrilus
Agrilus politus is a metallic wood-boring beetle in the family Buprestidae. The species is commonly known as the willow gall limb borer or common willow agrilus. It is associated with willow (Salix) hosts and has been documented as part of the prey provisions collected by the crabronid wasp Cerceris fumipennis. The species occurs in Central America and North America.
Altica bimarginata
willow flea beetle
Altica bimarginata is a small, shiny blue flea beetle in the family Chrysomelidae, commonly known as the willow flea beetle. It measures 5–6 mm in length and 2–3 mm in width. The species is distributed across North America and Central America and is frequently associated with willow plants (Salix genus). Three subspecies are recognized: A. b. bimarginata, A. b. labradorensis, and A. b. plicipennis. A neotype was designated for this species due to the loss of the original type specimen.
Anthocoris musculus
minute pirate bug
Anthocoris musculus is a species of minute pirate bug in the family Anthocoridae, found across Europe, Northern Asia (excluding China), and North America. At 3.4–4.0 millimeters, it is notably larger than many congeners. The species is associated with cottonwood, willow, and other deciduous trees and shrubs, and has been documented as a predator of red mites and eye-spotted bud moth in orchard settings.
Aphis farinosa
Small Willow Aphid
Aphis farinosa is a species of aphid commonly known as the Small Willow Aphid. It is a member of the family Aphididae and is associated with willow host plants. The species has been documented in parts of Europe, including Belgium and the Azores islands of Portugal.
Calligrapha multipunctata
common willow calligrapha, Common Willow Calligrapher Beetle
Calligrapha multipunctata is a leaf beetle in the family Chrysomelidae, commonly known as the common willow calligrapha. The species is native to North America and is associated with willow (Salix) as a host plant. Like other members of the genus Calligrapha, it exhibits distinctive elytral patterning. Three subspecies have been described, though one (C. m. suturella) may represent a separate species.
Caloptilia stigmatella
Willow Leafcone Caterpillar Moth
A small leaf-mining moth in the family Gracillariidae with a wingspan of 12–14 mm. Adults display distinctive red-brown forewings with a triangular white median costal blotch marked with blackish dots, and grey hindwings. The species has two adult flight periods annually and larvae feed on leaves of willows, poplars, and bog myrtle. It occurs across the Holarctic region, excluding the Balkan Peninsula.
Catocala unijuga
once-married underwing, once-married underwing moth
Catocala unijuga is a large underwing moth in the family Erebidae, first described by Francis Walker in 1858. Adults are characterized by cryptic forewings that conceal brightly patterned hindwings, a trait shared across the genus Catocala. The species is distributed across northern and western North America, with larvae feeding on poplars and willows. Adults fly from July to September in a single annual generation.
Chaitophorus viminicola
Chaitophorus viminicola is an aphid species in the subfamily Chaitophorinae, first described by Hille Ris Lambers in 1960. The specific epithet 'viminicola' refers to its association with willows (Salix viminalis and related species). It belongs to a genus specialized on Salicaceae, with most Chaitophorus species feeding on poplars and willows. Records indicate presence in the conterminous United States, though detailed biological studies remain limited.
Cimbex rubidus
Rusty Willow Sawfly
Cimbex rubidus, commonly known as the Rusty Willow Sawfly, is a large sawfly in the family Cimbicidae. Adults are robust, wasp-like insects with clubbed antennae characteristic of the family. Larvae feed on willow foliage and have a caterpillar-like appearance with seven pairs of prolegs, distinguishing them from lepidopteran caterpillars which have five or fewer pairs. The species is closely related to the Elm Sawfly (Cimbex americana) and shares many biological traits with other members of the genus.
Corythucha elegans
willow lace bug
Corythucha elegans, commonly known as the willow lace bug, is a small true bug in the family Tingidae. The species is specialized on willows (Salix spp.) as host plants and occurs across North America. Like other lace bugs, it possesses distinctive flattened, reticulated forewings that give it a delicate, lace-like appearance. The species was described by Carl J. Drake in 1918.
Cydia gallaesaliciana
Willow Gall Moth
A small tortricid moth known for inducing galls on willow (Salix) hosts. The species was described by Riley in 1881 and has been recorded from the northeastern United States, particularly Vermont. Like other Cydia species, it develops through complete metamorphosis with larval stages associated with plant tissue modification.
Dorytomus
Willow Weevils
Dorytomus is a genus of weevils established by Ernst Friedrich Germar in 1817. Species in this genus are primarily associated with willows and poplars (Salicaceae). The genus contains at least seven species, with distribution records spanning Europe, Asia, and North America. Dorytomus chinensis was recorded from Russia for the first time in 2023.
Enargia decolor
Pale Enargia, Aspen Twoleaf Tier Moth
A noctuid moth with boreal-transcontinental distribution across North America, primarily associated with trembling aspen and related poplar species. Adults are active in late summer, with larvae capable of reaching outbreak densities that cause extensive defoliation of host stands. The species shows a disjunct western distribution pattern that may represent cryptic diversity.
Euura ventralis
Willow Sawfly
Euura ventralis is a sawfly species in the family Tenthredinidae, commonly known as the Willow Sawfly. It is native to North America and has been recorded across multiple Canadian provinces including Alberta, British Columbia, Manitoba, and Ontario. As a member of the genus Euura, it is associated with willow (Salix) host plants. The species was first described by Thomas Say in 1824.
Graphocephala confluens
Willow Leafhopper
A sharpshooter leafhopper in the family Cicadellidae, Graphocephala confluens is a western North American species closely related to the more widely known candy-striped leafhopper (G. coccinea). Like other members of its genus, it possesses the characteristic brochosome coating that makes leafhoppers superhydrophobic and anti-reflective. The species is associated with willow and other woody plants in riparian and wetland habitats.
Gyascutus planicosta cribriceps
Gyascutus planicosta cribriceps is a subspecies of jewel beetle in the family Buprestidae, native to the southwestern United States and northern Mexico. It is one of the larger buprestid beetles in North America and is known to occur on willow (Salix) as well as other host plants. The subspecies is part of a complex that was formerly treated as a subgenus of Hippomelas but is now recognized as the distinct genus Gyascutus. Adults are active during summer months and can be collected by beating host vegetation or observed in flight.
Idiocerus
Idiocerus is a large genus of leafhoppers in the family Cicadellidae, first described by Lewis in 1834. The genus is taxonomically challenging, with many species exhibiting similar morphology that complicates identification. Species are predominantly associated with woody host plants, particularly poplars (Populus) and willows (Salix), though some species have been documented as pests of mango (Mangifera indica) in India. The genus has a broad distribution across the Holarctic region, with numerous species in both Europe and North America.
Nematus laticulus
Nematus laticulus is a species of sawfly in the family Tenthredinidae, subfamily Nematinae. It is a small, slender sawfly associated with willow (Salix) hosts. The species was described by Villaret in 1832 and is part of a large genus of primarily Holarctic distribution. Adults are active in spring and early summer.
Osmoderma
Typical Hermit Beetles, Hermit Beetles
Osmoderma is a genus of scarab beetles in the subfamily Cetoniinae, commonly known as hermit beetles. The genus has a Holarctic distribution, with species found across Europe, parts of Asia, and North America. Several European species, particularly O. eremita and O. barnabita, are of significant conservation concern due to habitat loss and are protected under the EU Habitats Directive. The genus is characterized by its dependence on tree hollows for larval development, making it highly vulnerable to forest management practices that remove dead wood and veteran trees.
saproxylicconservationHabitats-Directivetree-hollowsveteran-treesindicator-speciesumbrella-specieswood-mouldCetoniinaeScarabaeidaeHolarcticEuropeNorth-Americathreatened-speciesdead-woodforest-managementcitizen-sciencedetection-dogsex-situ-breedingpollardingtraditional-agricultural-landscapesmetapopulationhabitat-fragmentationold-growth-forestbroad-leaved-treesoaklimewillowbeechorchardshedgerowsurban-parkspheromone-monitoringradio-trackingphoretic-mitesScopoli-1763Le-Peletier-&-Serville-1828O.-eremitaO.-barnabitaO.-eremicolahermit-beetlePhyllonorycter scudderella
Phyllonorycter scudderella is a micro-moth in the family Gracillariidae. It is widespread across North America, with populations in the east from Ontario to Ohio and in the west from south-eastern Alaska to Oregon. The species is known to have two generations per year in at least part of its range. Larvae are leaf miners on willow species.
Plagiodera californica
California Willow Leaf Beetle
Plagiodera californica is a leaf beetle in the family Chrysomelidae. It is known from North America and has been observed on willow hosts. The species is part of a genus containing other leaf beetles associated with Salicaceae.
Plocamaphis flocculosa
Large Waxy Willow Aphid
Plocamaphis flocculosa is a large aphid species known for its conspicuous waxy covering. It is specialized on willows (Salix species) and produces dense flocculent wax secretions that give it a distinctive woolly appearance. The species is native to North America and has been introduced to parts of Europe, where it has established populations. Its common name directly references the characteristic waxy filaments that coat the body.
Poecilonota thureura
Poecilonota thureura is a species of metallic wood-boring beetle in the family Buprestidae. The species is found in North America, with records from Canada (Manitoba, Saskatchewan) and the United States. It has been collected as prey by the biosurveillance wasp Cerceris fumipennis, which specializes in capturing buprestid beetles. The species is considered uncommon in collections.
Pterocomma rufipes
Rufous Willow Bark Aphid
Pterocomma rufipes is a species of bark-feeding aphid in the family Aphididae, originally described from Europe by Hartig in 1841. The species is associated with willow (Salix) hosts and is characterized by its reddish leg coloration, referenced in its specific epithet. As a member of the genus Pterocomma, it exhibits the typical morphology of bark-dwelling aphids with reduced cornicles and a flattened body form adapted to living in crevices.
Pterocomma salicis
Black willow bark aphid
A bark-feeding aphid specialized on willow trees, commonly known as the black willow bark aphid. Forms mutualistic relationships with ants, particularly Lasius niger, which actively transport and tend colonies. The species has been documented in ant-mediated dispersal studies, suggesting ants may evaluate host quality when relocating aphid colonies.
Pterocomma smithiae
black willow aphid
Pterocomma smithiae is a species of aphid in the family Aphididae, commonly known as the black willow aphid. It is specialized on willow (Salix) hosts and is notable for its dark coloration and tendency to form dense colonies on twigs and branches. The species has been documented across North America and is frequently observed by naturalists.
Rabdophaga
Willow Gall Midges
Rabdophaga is a genus of gall midges in the family Cecidomyiidae comprising approximately 105 species distributed across Africa, Asia, Europe, and North America. The genus is predominantly associated with willows (Salix spp.), where larvae induce characteristic galls; most species are host-specific to particular willow species or sections. A notable exception is R. giraudiana, which forms stem galls on poplars (Populus spp.), and a 2016 record documents the first Rabdophaga species on a non-Salicaceae host, Symplocos cochinchinensis (Symplocaceae). Species within the genus exhibit varying degrees of host fidelity, with some showing strong preference-performance relationships and others demonstrating broader host ranges across willow sections.
Saperda vestita
Linden Borer
Saperda vestita is a longhorned beetle (Cerambycidae) native to North America, commonly known as the Linden Borer. The species was described by Thomas Say in 1824. Adults have been recorded from willow trees, and the species has been the subject of gut microbiome research comparing its bacterial associates to those of other wood-boring beetles.
Smerinthus
Eyed Hawkmoths
Smerinthus is a Holarctic genus of hawkmoths in the family Sphingidae, containing approximately 12 recognized species. Adults are characterized by prominent eyespots on the hindwings and forewing patterns that resemble dried leaves. Adults possess reduced or absent mouthparts and do not feed. Larvae feed on a variety of host plants in the families Salicaceae and possibly others.
Synanthedon albicornis
Western Willow Clearwing Moth
Synanthedon albicornis is a clearwing moth in the family Sesiidae, commonly known as the Western Willow Clearwing Moth. The species exhibits sexual dimorphism, with males possessing highly bipectinate (feathery) antennae and distinctive white thoracic tufts composed of hair-like scales. Like other sesiids, it is a wasp mimic with reduced wing scaling that creates a transparent appearance. The species is diurnal and generally not attracted to light traps.
Trichiosoma
Hairy-clubhorn Sawflies
Trichiosoma is a genus of large-bodied sawflies in the family Cimbicidae, comprising more than 30 described species. These insects are commonly known as Hairy-clubhorn Sawflies, reflecting their robust, often hairy appearance. Adults are active during summer months and are associated with woody vegetation. Larvae are solitary herbivores that feed on leaves.
Trichiosoma triangulum
Giant Birch Sawfly
A large sawfly in the family Cimbicidae, found in association with willow and birch habitats. Females deposit eggs into leaves, and the larvae are caterpillar-like herbivores that feed on foliage. Adults are active during summer months and are often observed on vegetation.
Tricholochmaea decora
Pacific willow leaf beetle, gray willow leaf beetle
Tricholochmaea decora is a skeletonizing leaf beetle in the family Chrysomelidae. It is commonly known as the Pacific willow leaf beetle or gray willow leaf beetle. The species is native to North America and belongs to a genus of leaf-feeding beetles. Two subspecies are recognized: T. d. decora and T. d. carbo.
Xylotrechus insignis
Willow Borer
Xylotrechus insignis is a species of longhorn beetle in the family Cerambycidae, described by John Lawrence LeConte in 1873. Commonly known as the Willow Borer, this beetle is recognized for its wood-boring larvae that tunnel into willow trees and related hosts, potentially causing significant damage or tree mortality. Adults measure 12–16 mm in length. The species is native to North America, with records from the United States and Mexico.