Pacific-northwest
Guides
Dorytomus sp-two-pnw
Dorytomus sp-two-pnw is an undescribed or provisionally named species of weevil in the tribe Dorytomini, known from the Pacific Northwest region of North America. Members of this genus are generally associated with willow (Salix) and poplar (Populus) hosts. This species has been documented in collections but lacks formal taxonomic description. Its biology and precise distribution remain incompletely known due to its provisional taxonomic status.
Drasteria parallela
Drasteria parallela is a noctuid moth in the family Erebidae, described in 2013 by Crabo and Mustelin. The species is endemic to the Pacific Northwest and northern California, restricted to middle-elevation forest habitats on exposed ridges. Adults are active in July and exhibit distinctive forewing patterns with parallel lines across a pale medial area, which inspired the species name.
Drepanosiphum oregonensis
Dark-streaked Maple Aphid
Drepanosiphum oregonensis is a North American aphid species described by Granovsky in 1939, commonly known as the Dark-streaked Maple Aphid. It belongs to the genus Drepanosiphum, which comprises aphids specialized on maple (Acer) host plants. The species is currently recognized as a synonym of Drepanosiphum oregonense in some taxonomic treatments. Very few observations exist in biodiversity databases, suggesting it may be uncommon, undercollected, or restricted to specific geographic regions.
Dyslobus verrucifer
Dyslobus verrucifer is a species of broad-nosed weevil in the family Curculionidae, subfamily Entiminae. It was described by Casey in 1895. The species is known from the Pacific Northwest region of North America, with records from British Columbia south through Washington, Oregon, Idaho, and Montana. Like other members of the tribe Byrsopagini, it is a flightless weevil with a compact, heavily sclerotized body form.
Dytoscotes pacificus
Dytoscotes pacificus is a species of rove beetle in the family Staphylinidae, subfamily Phloeocharinae. It was described by Smetana and Campbell in 1980. The species is known from Oregon in the western United States. Very little information is available about its biology, ecology, or specific habitat requirements.
Efferia frewingi
Columbia River Hammertail
Efferia frewingi is a species of robber fly (family Asilidae) described by Wilcox in 1966. Based on the genus Efferia, it belongs to a diverse group of predatory flies known for their robust bodies, large eyes, and aerial hunting behavior. The species epithet "frewingi" honors an individual, following the patronymic naming convention common in entomology. The common name "Columbia River Hammertail" suggests an association with the Columbia River region, though specific ecological details remain poorly documented in accessible literature.
Elachista galadella
Elachista galadella is a small moth species in the family Elachistidae, described by Kaila in 1999. It is known only from a single U.S. state, Washington, with no published records of its biology or ecology. Like other members of its genus, it likely has a narrow host plant association, though this remains undocumented for this species. The species exemplifies the poorly known microlepidopteran fauna of the Pacific Northwest.
Emblyna oregona
Emblyna oregona is a species of mesh-web weaver spider in the family Dictynidae, described by Gertsch in 1946. The species epithet "oregona" indicates an association with Oregon, suggesting a Pacific Northwest distribution. As with other members of the genus Emblyna, this species constructs irregular, tangled mesh webs rather than the spiral orb webs characteristic of many spiders. The genus Emblyna belongs to the family Dictynidae, a group of small to medium-sized spiders known for their cribellate silk production and preference for vegetation-dwelling habits.
Epimartyria bimaculella
Epimartyria bimaculella is a species of primitive moth in the family Micropterigidae, described in 2012 from specimens collected in the Pacific Northwest of North America. It is one of the smallest members of its genus, with forewings measuring 4.6–5.3 mm. The species is distinguished by two pale yellowish spots on dark fuscous forewings, a pattern referenced in its Latin name. It inhabits moist forest environments where leafy liverworts occur.
Episernus trapezoideus
Episernus trapezoideus is a small beetle species in the family Ptinidae (death-watch and spider beetles). It occurs in northwestern North America, with confirmed records from Alaska and British Columbia. The species was described by Fall in 1905. Available information on its biology and ecology is extremely limited.
Eratigena agrestis
Hobo Spider
Eratigena agrestis, commonly known as the hobo spider, is a funnel-web spider native to Europe that was introduced to the Pacific Northwest of North America in the early 20th century. It constructs characteristic funnel-shaped webs and lies in wait at the narrow end to capture prey. The medical significance of its bite remains poorly understood and debated. Spiderlings emerge in spring, contrasting with the fall emergence of the closely related E. atrica.
Ericaphis
blueberry aphids
Ericaphis is a genus of aphids in the family Aphididae, established by Börner in 1939. The genus includes species associated with Ericaceae, particularly Vaccinium species. Ericaphis fimbriata, the type species, is a significant pest of cultivated highbush blueberry (Vaccinium corymbosum) in the Pacific Northwest of North America. Species in this genus exhibit typical aphid life cycles with both aperous and alate morphs, and are known vectors of plant viruses.
Errhomus josephi
Errhomus josephi is a species of leafhopper in the family Cicadellidae, described by Oman in 1987. It belongs to the subfamily Errhomeninae and tribe Bathysmatophorini. The species is known from the Pacific Northwest region of the United States, with records from Oregon and Washington. As with many leafhopper species, detailed biological information remains limited in available literature.
Errhomus lineatus
Errhomus lineatus is a species of leafhopper in the family Cicadellidae, first described by Baker in 1898. It belongs to the subfamily Errhomeninae and tribe Bathysmatophorini. Distribution records indicate this species occurs in the Pacific Northwest region of North America, including British Columbia, Washington, Oregon, Idaho, and California. As with other leafhoppers, it is likely a phloem-feeding insect, though specific biological details remain poorly documented in the available literature.
Errhomus lineatus idahoensis
Errhomus lineatus idahoensis is a subspecies of leafhopper described by Oman in 1987. It belongs to the family Cicadellidae, subfamily Errhomeninae, a group of small, often inconspicuous planthoppers and leafhoppers. The subspecies is distributed in the Pacific Northwest region of North America, with records from Idaho, Oregon, Washington, California, and British Columbia. Like other members of its family, it is presumed to feed on plant sap using piercing-sucking mouthparts, though specific biological details remain poorly documented.
Errhomus praedictus
Errhomus praedictus is a species of leafhopper in the family Cicadellidae, described by Hamilton & Zack in 1999. It belongs to the subfamily Errhomeninae, a group of leafhoppers characterized by distinctive morphological features. The species is known from Washington State in the Pacific Northwest region of the United States. As a member of the Membracoidea superfamily, it shares the piercing-sucking mouthparts typical of Hemiptera.
Errhomus reflexus
Errhomus reflexus is a leafhopper species in the family Cicadellidae, described by Oman in 1987. It belongs to the subfamily Errhomeninae, a group of small to medium-sized leafhoppers often associated with coniferous and deciduous forest habitats. The species is known from Washington State in the Pacific Northwest region of North America. Like other members of the genus, it is presumed to feed on plant phloem, though specific host associations remain undocumented.
Errhomus similis
Errhomus similis is a species of leafhopper in the family Cicadellidae, subfamily Errhomeninae, described by Oman in 1952. It belongs to a genus of small, often inconspicuous leafhoppers associated with woody vegetation. The species is known from the Pacific Northwest region of North America.
Errhomus similis sobrinus
Errhomus similis sobrinus is a subspecies of leafhopper described by Oman in 1987. It belongs to the family Cicadellidae (leafhoppers), subfamily Errhomeninae, and tribe Bathysmatophorini. This subspecies is part of a group of Nearctic leafhoppers in the genus Errhomus, which are generally associated with coniferous and mixed forest habitats. The subspecies designation indicates geographic differentiation from the nominate form E. similis similis.
Errhomus similis zonarius
Errhomus similis zonarius is a subspecies of leafhopper in the family Cicadellidae, described by Oman in 1987. It belongs to the subfamily Errhomeninae, a group of leafhoppers characterized by distinctive morphological features. The subspecies is known from the Pacific Northwest region of North America, specifically Oregon and Washington. As with other members of the genus Errhomus, it likely inhabits herbaceous vegetation and feeds on plant sap.
Eusphalerum swauki
Eusphalerum swauki is a species of rove beetle in the family Staphylinidae, described by Hatch in 1957. It belongs to the subfamily Omaliinae, a group of small to medium-sized beetles often associated with decaying plant matter and fungal habitats. The species has a restricted distribution in western North America, with records from the Pacific Northwest and adjacent regions of Canada and the United States.
Euxoa costata
Euxoa costata is a noctuid moth species found in the Pacific Northwest of North America. It is particularly abundant in ponderosa pine forests east of the Cascade Mountains. The species has a wingspan of approximately 34 mm. Like other members of the genus Euxoa, it is a nocturnal species attracted to light.
Exochomus californicus Casey, 1899
Exochomus californicus is a small lady beetle species in the family Coccinellidae, described by Casey in 1899. Adults measure 3.5–4 mm in length and display distinctive coloration with black or brown elytra marked by yellow to orange patterns. The species has been documented across a restricted range in western North America, from Washington through Nevada to northern California. Like other members of Coccinellidae, it is presumed to be predatory, though specific ecological details remain poorly documented.
Fenderia capizzii
Fenderia capizzii is a species of rove beetle in the family Staphylinidae, described by Hatch in 1957. It belongs to the subfamily Euaesthetinae, a group of small staphylinids often associated with forest floor habitats. The species is known from Oregon, USA, and appears to have a restricted distribution within the Pacific Northwest.
Gloridonus xyston
Gloridonus xyston is a leafhopper species described by Hamilton in 2014. It belongs to the family Cicadellidae, a diverse group of sap-feeding insects commonly known as leafhoppers. The species is known from the Pacific Northwest region of North America.
Greya subalba
Greya subalba is a small moth in the family Prodoxidae, first described by Braun in 1921. It is found in dry steppe habitats of the Pacific Northwest and adjacent regions of western North America. The species is associated with Lomatium species, on which its larvae develop within developing seeds. Adults have a wingspan of 11–16 mm.
Gyros muirii
Cloaked Bantam
Gyros muirii is a small crambid moth species described by Henry Edwards in 1881. It occurs in the Pacific Northwest region of North America, with records from California, Oregon, and Washington. Adults fly from spring through mid-summer and are characterized by distinctive orange-brown forewings with dark markings. Two subspecies are recognized: the nominate form and G. m. rubralis from California.
Hadronema incognitum
Hadronema incognitum is a species of plant bug in the family Miridae, described by Forero in 2008. The species epithet "incognitum" (meaning unknown or unrecognized) likely reflects its prior confusion with congeners or its cryptic nature. As a member of the diverse Miridae family, it belongs to one of the largest families of true bugs. The species is known from a limited number of specimens in the Pacific Northwest and California.
Hapalaraea megarthroides
Hapalaraea megarthroides is a rove beetle in the subfamily Omaliinae, first described from the Pacific Northwest region. The species belongs to a genus characterized by compact body form and association with forest floor habitats. Records indicate it occurs in western North America from British Columbia to California.
Harpaphe haydeniana
yellow-spotted millipede, almond-scented millipede, cyanide millipede
Harpaphe haydeniana is a flat-backed millipede native to the Pacific coast of North America, recognized by its black body with yellow-tipped lateral keels. The species is notable for its chemical defense system, secreting hydrogen cyanide when threatened, which produces a characteristic almond odor. It plays a significant role in forest decomposition, particularly in redwood ecosystems. Despite its common names suggesting uniqueness, both the color pattern and cyanide defense occur in other flat-backed millipedes globally.
Hemicrepidius pallidipennis
Hemicrepidius pallidipennis is a species of click beetle in the family Elateridae. It occurs in the Pacific Northwest of North America, including Washington, Oregon, British Columbia, and Alaska. The species was described by Mannerheim in 1843.
Hippodamia washingtoni
Washington's Lady Beetle
Hippodamia washingtoni is a species of lady beetle in the family Coccinellidae. Adults measure 5.40–6.70 mm in length. The species is known from a restricted range in the Pacific Northwest of North America.
Ilybius vancouverensis
Ilybius vancouverensis is a species of predaceous diving beetle in the family Dytiscidae, first described by Leech in 1937. It was originally placed in the genus Agabus before being transferred to Ilybius. The species is known from the Pacific Northwest of North America, with records from British Columbia, Canada and Alaska, United States. Like other members of the genus, it is an aquatic predator inhabiting freshwater environments.
Ischnura erratica
Swift Forktail
Ischnura erratica, the swift forktail, is a robust damselfly native to the Pacific Northwest. Adults are 30–35 mm long with a wingspan of 35–40 mm. Males display distinctive blue and black coloration with a forked tail on abdominal segment 10, while females occur in two color phases. It is one of the earliest damselflies to emerge each year and breeds in clear waters across diverse aquatic habitats.
Isolachus
Isolachus is a genus of armoured harvestmen in the family Cladonychiidae, containing a single described species, I. spinosus. The genus was established by Briggs in 1971 and is known from the Pacific Northwest region of the United States. As a member of the suborder Laniatores, it belongs to a diverse group of short-legged harvestmen characterized by heavily sclerotized body armor.
Isolachus spinosus
Isolachus spinosus is a species of harvestman (Opiliones) in the family Cladonychiidae, described by Briggs in 1971. It belongs to the suborder Laniatores, a diverse group of short-legged harvestmen often associated with moist microhabitats. The species is known from limited records in the Pacific Northwest of North America.
Katianna
Katianna is a genus of globular springtails (Collembola: Symphypleona) with worldwide distribution. Members are distinguished by their minute size (approximately 1 mm), hairy antennae, and abundant setae covering the abdomen, particularly toward the posterior. The genus has been recorded across diverse regions including Europe, the Andes, Central Australia, the Caribbean, and Antarctica. A putative undescribed species from the Pacific Northwest, informally designated "Katianna species 10" or "Mtn Dew Katianna," was first documented in 2016 and rediscovered in 2024.
Lara avara
riffle beetle
Lara avara is a xylophagous riffle beetle in the family Elmidae. It inhabits freshwater streams in western North America, where larvae feed on submerged decaying wood. The life cycle spans 4–6 years, with extended larval development and brief adult emergence from May to August. The species contributes to aquatic wood decomposition through larval feeding and fecal production.
Lasionycta caesia
Lasionycta caesia is a noctuid moth restricted to high-elevation alpine habitats in the Pacific Northwest. It was described in 2009 as part of a comprehensive revision of the genus Lasionycta. The species occurs exclusively in rocky alpine tundra near tree line in the Cascade Mountains of northern Washington and the British Columbia Coast Range, extending north to 58° latitude. Adults are active for a brief period from mid-July to mid-August.
Lasionycta fergusoni
Lasionycta fergusoni is a nocturnal moth in the family Noctuidae, described by Crabo & Lafontaine in 2009. It inhabits subalpine forests across the Pacific Northwest and western Canada, from southern Washington through British Columbia and Alberta to southern Yukon. Adults are active from late June to mid-August. The species is part of a genus revision that described 17 new North American species.
Lasionycta silacea
Lasionycta silacea is a noctuid moth described by Crabo & Lafontaine in 2009 as part of a major revision of the genus Lasionycta. It inhabits high-elevation coniferous forests near the treeline in the Pacific Northwest and adjacent Rocky Mountains. The species is nocturnal and has a relatively restricted geographic range spanning from the British Columbia Coast Range and Washington Cascades to extreme southwestern Alberta.
Lasionycta subfuscula
A noctuid moth of western North America, ranging from southwestern British Columbia and Alberta through the Rocky Mountains to southern Oregon, Colorado, and Utah. Adults fly from mid-June to early September in transition zone and subalpine forests. Two subspecies are recognized: L. s. subfuscula in the southern Rocky Mountains and L. s. livida in the Pacific Northwest.
Lasiopogon puyallupi
Salish Sea Sandpirate
Lasiopogon puyallupi is a robber fly (Diptera: Asilidae) native to the Pacific Northwest of North America. The species was originally described as a subspecies of L. willametti by Cole & Wilcox in 1938, then elevated to full species status in 2020 based on molecular and morphological evidence. It belongs to the bivittatus section of the genus Lasiopogon. The common name "Salish Sea Sandpirate" reflects its coastal habitat association.
Latridius protensicollis
Latridius protensicollis is a species of minute brown scavenger beetle in the family Latridiidae, described by Mannerheim in 1843. This species is known from the Pacific Northwest of North America, with records from British Columbia, Canada and Alaska, United States. Like other members of Latridiidae, it is a small beetle associated with moist, decaying organic matter.
Litiulus
Litiulus is a monotypic genus of millipedes in the family Parajulidae, containing only Litiulus alaskanus. It is endemic to the northeastern Pacific coastal region, ranging from Tlingit territory in the north to Haida territory in the south. The species is notable for its specialized diet of fungal fruiting bodies and slime molds, and its occurrence in hypermaritime old-growth rainforests.
Litiulus alaskanus
Litiulus alaskanus is a small julid millipede and the sole species in the monotypic genus Litiulus. It is endemic to the northeastern Pacific region, where it inhabits old-growth rainforests. The species is notable for its specialized diet of fungal fruiting bodies and its apparent physiological tolerance for drier conditions than most sympatric millipedes.
Lophocampa roseata
Rosy Aemilia
Lophocampa roseata, commonly known as the rosy aemilia, is a small moth in the family Erebidae. It was described by Francis Walker in 1866. The species is restricted to the Pacific Northwest region of North America, where it inhabits coniferous forests and has adapted to urban environments. The forewings measure 14–15 mm in length. Larvae have been successfully reared on Douglas-fir (Pseudotsuga menziesii), indicating a host relationship with this conifer species.
Lordithon oregonus
Lordithon oregonus is a species of rove beetle (Staphylinidae) described by Campbell in 1982. The species was originally described under the genus Lordithon but has been synonymized under Bobitobus oregonus in some taxonomic treatments. It is known from the Pacific Northwest region of North America, with records from British Columbia, California, Oregon, and Washington. The genus Lordithon belongs to the tribe Xantholinini within the subfamily Staphylininae.
Macrophya oregona
Macrophya oregona is a sawfly species in the family Tenthredinidae, first described by Cresson in 1880. The species is native to western North America, with records from British Columbia, Canada, and Alaska, United States. As a member of the genus Macrophya, it belongs to a group of sawflies that are typically associated with woody plants. Very little detailed biological information has been published specifically for this species.
Macrosiphum oregonense
Western Skunk-cabbage Aphid
Macrosiphum oregonense is an aphid species described by Jensen in 2000. It belongs to the large genus Macrosiphum within the family Aphididae. The species is commonly known as the Western Skunk-cabbage Aphid, indicating an association with skunk-cabbage plants (Lysichiton species). As a member of the Macrosiphum genus, it shares characteristics with other large aphids in this group, including long antennae and typically having both winged and wingless morphs. The species has been documented through limited observations, with only 3 records in iNaturalist as of the data cutoff.