Western-north-america
Guides
Abagrotis discoidalis
Abagrotis discoidalis is a noctuid moth described by Grote in 1876, with a wingspan of approximately 31 mm. It is restricted to western North America, ranging from southern Alberta south through the Rocky Mountain states to northern Arizona and New Mexico. Adults are active from June to August in Alberta, with a single annual generation.
Abagrotis dodi
Abagrotis dodi is a noctuid moth described by James Halliday McDunnough in 1927. It occurs in western North America from southern Yukon through the Rocky Mountain region to Utah, Colorado, Nevada, and Washington. Adults fly in late summer with a single annual generation. The species is known from relatively few observations.
Abagrotis glenni
Abagrotis glenni is a noctuid moth described by Buckett in 1968. It occurs in western North America from British Columbia south to California and east to Utah. Adults are active in spring, with larvae feeding on coniferous host plants.
Abagrotis hermina
Abagrotis hermina is a moth species in the family Noctuidae, described by J. Donald Lafontaine in 1998. It is a medium-sized noctuid with a wingspan of approximately 31 mm. The species is distributed across western North America, occurring in the Canadian provinces of Manitoba, Saskatchewan, Alberta, and British Columbia, as well as the U.S. states of Utah and California.
Abagrotis mirabilis
Abagrotis mirabilis is a noctuid moth described by Augustus Radcliffe Grote in 1879. It occurs in western North America from British Columbia to California. The species has a wingspan of approximately 35 mm. Larvae feed on Juniperus and Cedrus species.
Abagrotis nanalis
Abagrotis nanalis is a small noctuid moth described by Grote in 1881. It occurs in western North America from southern British Columbia to western North Dakota and south to northern New Mexico and California. Adults are active in late summer with a single annual generation in Alberta.
Abagrotis reedi
Reed's Dart
Abagrotis reedi is a noctuid moth described by John S. Buckett in 1969. It occurs across western and central North America, from California through the Rocky Mountain states to Iowa, with Canadian populations in the prairie provinces and British Columbia. The species has a moderate wingspan of 33–36 mm. It is one of approximately 30 species in the genus Abagrotis, a group of dart moths primarily distributed in North America.
Abagrotis scopeops
Abagrotis scopeops is a noctuid moth described by Harrison Gray Dyar Jr. in 1904. It is a western North American species with a wingspan of approximately 36 mm. Adults are active in early fall. The species is relatively well-documented with 95 iNaturalist observations.
Acalymma trivittatum
Western Striped Cucumber Beetle
Acalymma trivittatum, the western striped cucumber beetle, is a specialist leaf beetle native to western North America. It is a key agricultural pest of cucurbit crops including melons, cucumbers, squash, and pumpkins. The species is closely related to the eastern striped cucumber beetle (Acalymma vittatum), with which it shares similar biology and damage potential. Both adults and larvae cause significant economic injury through direct feeding damage and transmission of bacterial wilt pathogen Erwinia tracheiphila.
Aceratagallia curvata
Aceratagallia curvata is a leafhopper species in the family Cicadellidae, originally described as Ceratagallia curvata by Oman in 1933. The species has since been reclassified into the genus Aceratagallia. It is known from the western United States, with records from California, Nevada, Oregon, and Utah.
Aceria calaceris
Rocky Mountain maple felt mite
Aceria calaceris, the Rocky Mountain maple felt mite, is an eriophyid mite that induces distinctive felt-like galls called erinea on maple leaves. This microscopic species was first described by Hartford H. Keifer in 1952 from Fallen Leaf Lake. It has a complex life cycle involving two female morphs—protogynes for reproduction and deutogynes for overwintering—plus a single male form. The species is found in the western United States and Canada, where it specializes on three maple species.
Aceria mackiei
Live Oak Erineum Mite
Aceria mackiei, commonly known as the live oak erineum mite, is an abundant eriophyoid mite that induces distinctive leaf-blister galls on several species of live oak. This mite is notable for its unique ability to form galls on oaks belonging to both the black oak group and the intermediate oak group, a trait not shared by other eriophyoid mites. The species is widely distributed across western North America and was previously classified under the genus Eriophyes.
Acholla ampliata
Acholla ampliata is an arboreal assassin bug in the family Reduviidae, distributed across western North America from California to Colorado and south to Arizona, New Mexico, and Mexico. Adults are most active in autumn, though they can be found from July onward. The species is distinguished from similar assassin bugs by its relatively smooth body lacking prominent leg spines. It preys on caterpillars and other insects associated with trees, including pest species such as the Codling Moth.
Acinopterus viridis
Acinopterus viridis is a species of leafhopper in the family Cicadellidae, described by Ball in 1903. It belongs to the tribe Acinopterini within the subfamily Deltocephalinae. The species is known from western North America, with distribution records from Alberta, Arizona, British Columbia, California, and Colorado. As a member of the leafhopper family, it is presumed to feed on plant sap, though specific host plants and ecological details remain poorly documented.
Aciurina
Aciurina is a genus of gall-inducing tephritid flies distributed in western North America. Species in this genus induce distinct morphological galls on host plants in the Asteraceae family, particularly genera such as Chrysothamnus, Gutierrezia, and Baccharis. The genus has been taxonomically challenging due to overlapping wing patterns among species, but gall morphology provides reliable diagnostic characters. Several species are unusually abundant in the southwestern United States and serve as ecosystem engineers that support complex arthropod communities.
Aciurina bigeloviae
Cotton-gall Tephritid
Aciurina bigeloviae is a gall-inducing tephritid fly native to western North America that forms distinctive white, woolly 'cotton' galls on Ericameria nauseosa (rabbitbrush), specifically the variety graveolens. The species was originally described as Trypeta bigeloviae by Cockerell in 1890. It exhibits Type I wing pattern morphology and produces spherical cotton galls that serve as microhabitats for complex arthropod communities. The species is sister to A. trixa, with which it occurs sympatrically in New Mexico, though the two species produce markedly different gall types.
Aciurina ferruginea
Medusa Gall Tephritid
Aciurina ferruginea is a gall-forming tephritid fly known as the Medusa Gall Tephritid. It forms distinctive pear-shaped galls on Chrysothamnus viscidiflorus (sticky rabbitbrush) by ovipositing eggs into axillary bud exudate. Adults exhibit visual communication through wing displays, which likely function in species recognition and courtship. The species has been documented in the western United States.
Aclypea bituberosa
Western Spinach Carrion Beetle, Spinach Carrion Beetle
Aclypea bituberosa is a phytophagous carrion beetle in the family Silphidae, notable for being herbivorous rather than necrophagous like most of its relatives. Adults and larvae feed on leaves and shoots of various crop plants, particularly spinach and beets, causing occasional agricultural damage. The species has a single generation per year, overwintering as adults. It is restricted to the northwestern quarter of North America.
Acmaeodera angelica
Acmaeodera angelica is a metallic woodboring beetle in the family Buprestidae. The species was described by Fall in 1899 and occurs in western North America. It belongs to a genus of flower-visiting buprestids, with adults frequently found on blossoms of various host plants. The species is one of approximately two dozen Buprestidae associated with Cercocarpus (mountain mahogany) in North America, and has been confirmed breeding within dead branches of this plant genus.
Acmaeodera connexa
metallic wood-boring beetle
Acmaeodera connexa is a species of metallic wood-boring beetle in the family Buprestidae, first described by LeConte in 1859. The species is found in North America, particularly associated with the genus Cercocarpus (mountain mahogany) in western North America. It is one of approximately two dozen buprestid species associated with Cercocarpus, and has been confirmed breeding within dead branches of these plants.
Acmaeodera diffusa
Acmaeodera diffusa is a metallic wood-boring beetle in the family Buprestidae, described by Barr in 1969. The species is known from western North America, with records from Utah and surrounding regions. Adults are flower visitors, frequently collected from blooms of pricklypear cacti (Opuntia), globemallow (Sphaeralcea), and other desert forbs. Like other Acmaeodera species, larvae likely develop in dead or dying woody plants, though specific host associations remain incompletely documented.
Acmaeodera dolorosa
Acmaeodera dolorosa is a species of metallic wood-boring beetle in the family Buprestidae. It is found in North America. Two subspecies are recognized: A. dolorosa dolorosa Fall, 1899 and A. dolorosa liberta Fall, 1922. The species is one of approximately two dozen jewel beetles associated with Cercocarpus (mountain mahogany) in western North America.
Acmaeodera knowltoni
Acmaeodera knowltoni is a metallic wood-boring beetle in the family Buprestidae, first described by Barr in 1969. The species occurs in western North America, with documented records from Utah and surrounding regions. Adults are flower-visitors, frequently collected from blooms of Sphaeralcea, Penstemon, Rosa woodsii, and other flowering plants. The species is larger than the similar A. rubronotata, with uniformly orange rather than yellow elytral flecks with red towards the apices.
Acmaeodera mariposa
Mariposa Jewel Beetle
Acmaeodera mariposa is a metallic wood-boring beetle in the family Buprestidae, described by Horn in 1878. The species is found in North America and comprises two subspecies: A. m. mariposa and A. m. dohrni. It belongs to a group of jewel beetles associated with Cercocarpus (mountain mahogany) host plants in western North America, with confirmed breeding records from dead branches of this plant genus.
Acmaeodera mariposa dohrni
Acmaeodera mariposa dohrni is a subspecies of jewel beetle in the family Buprestidae. It is one of approximately two dozen buprestid species associated with Cercocarpus (mountain mahogany) in western North America. The species is part of the Acmaeodera mariposa complex, which includes the nominate subspecies A. m. mariposa. This subspecies has been confirmed breeding in dead branches of Cercocarpus ledifolius and is among five buprestid species exclusively associated with this host genus.
Acmaeodera nelsoni
Acmaeodera nelsoni is a species of jewel beetle in the family Buprestidae, described by Barr in 1972. It belongs to the nominate subgenus Acmaeodera (s. str.). The species has been documented as associated with Cercocarpus ledifolius (curl-leaf mountain mahogany), a host relationship confirmed through rearing records. It is one of approximately two dozen North American Buprestidae species linked to Cercocarpus hosts, with several species in this genus being Cercocarpus specialists.
Acmaeodera nexa
Acmaeodera nexa is a species of metallic wood-boring beetle in the family Buprestidae, first described by Henry Clinton Fall in 1922. It is one of approximately 150 species in the genus Acmaeodera in North America, a taxonomically challenging group often referred to as jewel beetles due to their metallic coloration. The species is associated with Cercocarpus (mountain mahogany) in western North America, where adults have been observed and larvae likely develop in dead branches.
Acmaeodera plagiaticauda
Acmaeodera plagiaticauda is a species of metallic wood-boring beetle in the family Buprestidae, described by George Henry Horn in 1878. It is one of approximately two dozen North American Buprestidae species associated with Cercocarpus (mountain mahogany), a genus of shrubs and small trees in the rose family. Nine species in this association have been confirmed as breeding within dead branches of Cercocarpus, with five species, including A. plagiaticauda, having been recorded exclusively from this host genus. The species is distributed in western North America, particularly in mountainous regions where its host plant occurs.
Acmaeodera pubiventris pubiventris
Acmaeodera pubiventris pubiventris is a subspecies of jewel beetle in the family Buprestidae, native to western North America. It belongs to the nominate subspecies of Acmaeodera pubiventris. Adults are active during summer months and have been associated with woody host plants in the genus Cercocarpus.
Acmaeodera vandykei
Acmaeodera vandykei is a jewel beetle species in the family Buprestidae, described by Fall in 1899. It belongs to the large genus Acmaeodera, which contains approximately 150 species in North America. The species is known to be associated with Cercocarpus (mountain mahogany) in western North America, where adults have been reared from dead branches. Like other members of its genus, adults likely feed on pollen from flowers.
Acmaeodera variegata
Acmaeodera variegata is a metallic wood-boring beetle in the family Buprestidae, native to North America. The species was described by LeConte in 1852. It has been collected from flowers of Fallugia paradoxa (Apache plum) and Verbesina encelioides (cowpen daisy) in Arizona, and is associated with Cercocarpus (mountain mahogany) as a larval host. The species is part of the diverse Acmaeodera fauna of western North America.
Acneus
water-penny beetles
Acneus is a genus of water-penny beetles (family Psephenidae) containing four described species. The genus is characterized by flattened, oval larvae that cling to submerged rocks in flowing water. Adults are terrestrial and rarely encountered. The genus was established by Horn in 1880 and is restricted to western North America.
Acneus quadrimaculatus
water penny beetle
Acneus quadrimaculatus is a species of water penny beetle in the family Psephenidae. It is endemic to the United States with confirmed records from California and Oregon. Adults are found in riparian vegetation near aquatic habitats. The species was described by Horn in 1880.
Acontia coquillettii
bird dropping moth
Acontia coquillettii is a small noctuid moth species native to western North America. It is characterized by its predominantly white forewings with distinctive grey and olive markings on the distal portion, a pattern that serves as camouflage resembling bird droppings. The species has been documented in California and Oregon, with specific records from the Snake River region in Malheur County. It is one of approximately 20 species in the genus Acontia found in North America.
Acossus populi
aspen carpenterworm
Acossus populi is a moth in the family Cossidae, commonly known as the aspen carpenterworm. The species has a wingspan of 50–68 mm. It is distributed across western North America, including the western United States and parts of Canada. The larvae are specialized feeders on Populus species, particularly trembling aspen (Populus tremuloides). The species was first described by Francis Walker in 1856.
Acossus undosus
Acossus undosus is a species of carpenter moth in the family Cossidae. The species was described by Lintner in 1878. It has been documented in Wyoming and Utah, with possible occurrence in surrounding states. The wingspan is approximately 58 mm.
Acrolepiopsis californica
Acrolepiopsis californica is a small moth in the family Glyphipterigidae. The species is known from western North America, with documented occurrences in western California, western Oregon, and Alberta. Forewing length ranges from 4.4 to 6.7 mm. Larvae are known to mine the fruits of several Lilium species and Disporum hookeri.
Acrolophus laticapitana
Grass Tube Moth
Acrolophus laticapitana is a small moth in the family Acrolophidae, described by Walsingham in 1884. The species is found in western North America from northern California to southern Arizona. Adults have forewings measuring 6.5–9.5 mm in length. Like other members of the genus, it is commonly known as a "grass tube moth" due to larval behavior. The species includes two recognized subspecies: the nominate form and A. l. unistriganus described by Dyar in 1903.
Acronicta cyanescens
Blue-gray Dagger
Acronicta cyanescens is a medium-sized noctuid moth of western North America, commonly known as the Blue-gray Dagger. First described by George Hampson in 1909, this species is distinguished by its blue-gray coloration and dagger-like markings. Adults are active during summer months, with a single generation per year. The species belongs to a genus whose caterpillars are often called 'dagger moths' due to their distinctive posterior projections.
Acronicta impressa
Impressive Dagger, Impressive Dagger Moth, Willow Dagger Moth
Acronicta impressa is a noctuid moth commonly known as the impressive dagger moth or willow dagger moth. The species was first described by Francis Walker in 1856. It ranges across western North America from Canada to northwestern Mexico. Adults are active in early to midsummer and are attracted to light. The caterpillars feed on a variety of woody plants including willow, poplar, and rose.
Acronicta lupini
lupine dagger, little bear
Acronicta lupini is a noctuid moth found in alpine habitats across western North America, from Canadian provinces and territories south to California. The species was described by Augustus Radcliffe Grote in 1873. Adults have a wingspan of approximately 33 mm and are active from May through August. The common names "lupine dagger" and "little bear" refer to this species' appearance and possibly its association with lupine plants.
Acronicta mansueta
gentle dagger moth
Acronicta mansueta, commonly known as the gentle dagger moth, is a species of owlet moth in the family Noctuidae. First described by John Bernhardt Smith in 1897, it was treated as a synonym of Acronicta falcula for much of the 20th century before being reinstated as a valid species in 2011. The species is widespread across western North America.
Acronicta othello
Acronicta othello is a noctuid moth described by Smith in 1908. It belongs to the dagger moth genus Acronicta, a group characterized by distinctive dark markings on the forewings that often resemble daggers or swords. The species occurs in western North America, with records from California and surrounding regions. Like other members of its genus, it is presumed to be nocturnal and attracted to light sources.
Acronicta strigulata
Strigulose Dagger
Acronicta strigulata is a moth in the family Noctuidae, commonly known as the Strigulose Dagger. It is a western North American species with a documented range from British Columbia southward to California. The species has a wingspan of approximately 35 mm. Limited published information exists regarding its biology and natural history.
Adejeania
orange bristle fly
Adejeania is a genus of tachinid flies native to the Americas, with most species occurring in South America. The genus name derives from an alteration of 'Dejeania,' meaning 'not Dejeania.' The most widely distributed species, A. vexatrix, ranges from Mexico through western North America to British Columbia and Alberta. These flies are parasitoids of caterpillars and are important flower visitors in late summer and fall.
Adejeania vexatrix
Orange Bristle Fly
Adejeania vexatrix is a large, conspicuous tachinid fly of western North America, immediately recognizable by its bright orange abdomen, heavy black setae, and uniquely elongated palpi that project forward like a beak. Adults are active flower visitors from mid-summer through early autumn, with populations persisting later in southern portions of the range. This species is a known parasitoid of caterpillars, though specific host records remain undocumented.
Adela flammeusella
Fairy Longhorn Moth
Adela flammeusella is a species of fairy longhorn moth in the family Adelidae, characterized by the extremely long antennae typical of this group. Males possess antennae up to three times the length of the forewings, while females have antennae roughly twice as long. The species was described by V.T. Chambers in 1876 and is restricted to the Pacific coastal region of western North America.
Adela septentrionella
Ocean Spray Fairy Moth, Fairy Longhorn Moth
Adela septentrionella is a small fairy longhorn moth in the family Adelidae, described by Walsingham in 1880. The species is characterized by the exceptionally long antennae typical of male adelids, with forewings measuring 4.5–5.7 mm. Adults are active from mid-April to mid-July across their western North American range. The larvae are specialized feeders on the buds of Holodiscus discolor (ocean spray), a woody shrub in the rose family.
Adela trigrapha
Three-striped Longhorn
Adela trigrapha is a fairy longhorn moth in the family Adelidae, described by Zeller in 1876. It occurs in western North America from Vancouver Island to California. Adult males display striking sexual dimorphism with extremely long antennae and black forewings marked by three white lines, while females have shorter antennae, orange heads, and metallic blue-purple wings. The species belongs to a family characterized by elongated antennae, particularly in males.
Adelges cooleyi
Cooley spruce gall adelgid, Douglas fir adelgid, gall adelgid
Adelges cooleyi is a gall-forming adelgid native to western North America, specifically the Rocky Mountains and Cascade Mountains. It is a host-alternating species with a complex life cycle involving two primary hosts: spruce (Picea) species as primary hosts and Douglas fir (Pseudotsuga menziesii) as the secondary host. On spruce, the adelgid induces the formation of distinctive pineapple-shaped galls at branch terminals. On Douglas fir, it produces white, cottony wax masses containing eggs but causes less conspicuous injury. The species has two generations per year and exhibits morphological dimorphism: progredientes migrate to current-year needles while sistentes settle on older needles.