Holarctic
Guides
Coenomyia
stink fly
Coenomyia is a genus of flies in the family Xylophagidae, commonly known as "stink flies." The genus contains at least four described species, including the widespread Coenomyia ferruginea. These flies are characterized by their large size, brown coloration, and slow, clumsy movements. The family name Xylophagidae derives from Greek roots meaning "wood-eating," reflecting the larval habitat in dead and decaying wood where they prey on wood-boring beetle larvae.
Coenonympha
heaths, ringlets
Coenonympha is a genus of brush-footed butterflies in the subfamily Satyrinae, containing species distributed across temperate regions of the Holarctic. Palearctic species are commonly called heaths, while Nearctic species are called ringlets. The genus exhibits complex evolutionary patterns involving hybrid speciation, with some species complexes showing homoploid hybrid speciation and extensive gene flow. Many species are habitat specialists associated with peatlands, salt marshes, or alpine meadows, and several are of conservation concern due to habitat degradation.
Coenonympha tullia
large heath, common ringlet
Coenonympha tullia is a Holarctic butterfly species in the family Nymphalidae, found across northern Europe, Asia, and North America. The species inhabits diverse grassy environments including peat bogs, wet meadows, prairies, and arctic tundra. It serves as a flagship species for peatland restoration efforts, with documented reintroduction programs in the UK. The species exhibits poor flight capability and has been observed seeking new grounds along ditches. Multiple subspecies have been described across its broad range, with some forms formerly considered subspecies now elevated to species rank.
Coenonympha tullia kodiak
Kodiak Ringlet
Coenonympha tullia kodiak is a subspecies of the Large Heath butterfly, commonly known as the Kodiak Ringlet. It belongs to the subfamily Satyrinae within the brush-footed butterfly family Nymphalidae. This subspecies is part of a widespread Holarctic species complex that exhibits considerable geographic variation across its range. The Kodiak Ringlet is associated with peatland and bog habitats, reflecting the broader ecological affinity of the C. tullia complex for wetland environments.
Coenonympha tullia mcisaaci
Coenonympha tullia mcisaaci is a subspecies of the common ringlet butterfly, a member of the family Nymphalidae. It belongs to a genus of small brown butterflies commonly associated with grassland and bog habitats. The subspecies is part of a widespread Holarctic species complex with variable taxonomy across its range.
Coenonympha tullia subfusca
Coenonympha tullia subfusca is a subspecies of the large heath butterfly, a member of the family Nymphalidae. It is associated with peatland and bog habitats, where it occurs alongside other bog-specialist species. The subspecies is part of a complex that shows variation across its range in Europe and North America. Like other Coenonympha species, it is dependent on specific habitat conditions that have become increasingly threatened by drainage, peat extraction, and climate change-induced wildfires.
Coleophora ledi
Coleophora ledi is a small case-bearing moth (family Coleophoridae) with a wingspan of 10–13 mm. It has a trans-Holarctic distribution, occurring across northern Eurasia from Fennoscandia to Japan, and in North America in eastern Canada, Michigan, and Alaska. The species is notable for its larval specialization on Ericaceae shrubs, particularly Ledum and Chamaedaphne species.
Colias hecla
Hecla Sulphur, Northern Clouded Yellow
A small to medium-sized sulphur butterfly of the Pieridae family, restricted to high-latitude and high-altitude regions of the Northern Hemisphere. The species shows pronounced sexual dimorphism in wing pattern, with females displaying distinctive yellow 'windows' interrupting the black marginal band. First described from Greenland, where it occurs without congeners. Multiple subspecies are recognized across its fragmented Holarctic range.
Colias palaeno
Moorland Clouded Yellow, Palaeno Sulphur, Pale Arctic Clouded Yellow
Colias palaeno is a Holarctic butterfly species in the family Pieridae, occurring across northern Eurasia and North America. It inhabits moorlands, bogs, and open coniferous forests, with southern populations restricted to high alpine zones above 1,500 meters. The species has experienced significant declines in parts of its European range, particularly in Bavaria, where larval survival depends critically on microclimatic conditions associated with Sphagnum moss. It is univoltine, with adults flying from June to August.
Colias tyche
Booth's sulphur, pale Arctic clouded yellow
Colias tyche is a small to medium-sized butterfly in the family Pieridae, distinguished by its pale green to greenish-white or greenish-yellow wings with visible brown veins and grey-green suffusion on the hindwing bases. The species exhibits sexual dimorphism in wing borders: males have dark borders with pale yellow spots, while females have wider dark borders with black spots. It is one of the northernmost Colias species, with a Holarctic distribution spanning Arctic and subarctic regions of North America and Eurasia. The species name references Tyche, the Greek deity of chance and luck.
Colonidae
Colonidae is a small family of beetles in the superfamily Staphylinoidea, commonly known as colon beetles. The family contains approximately 50 described species in the single genus *Colon*. These beetles are small, compact, and primarily associated with decaying organic matter and fungi. They are closely related to the rove beetles (Staphylinidae) but are distinguished by their more rounded body form and reduced elytra that still cover most of the abdomen.
Colymbetes dolabratus
Colymbetes dolabratus is a predaceous diving beetle in the family Dytiscidae. It has a Holarctic distribution, occurring in both North America and the Palearctic region. The species belongs to the genus Colymbetes, a group of medium-sized diving beetles adapted to aquatic habitats.
Cordilura
Cordilura is a large genus of dung flies (Scathophagidae) comprising approximately 90 species worldwide. The genus is primarily distributed across the Holarctic region, with the greatest diversity in the Palaearctic and Nearctic regions. Larvae are known to serve as prey for predatory insects such as Orthacheta hirtipes.
Cordulegastridae
Spiketails, biddie, flying adder
Cordulegastridae, commonly known as spiketails, is a family of dragonflies (Anisoptera) distributed across the Holarctic region. The family contains approximately 51 species in three to four genera, including Cordulegaster, Anotogaster, Neallogaster, and the recently restored Thecagaster and Zoraena. Adults are characterized by large black or brown bodies with yellow markings, blue-green eyes that meet at a single point, and a slow flight pattern 30–70 cm above water. Nymphs are specialized ambush predators that conceal themselves in sand or silt substrates of clean, flowing streams.
Corticaria dentiventris
Corticaria dentiventris is a minute beetle in the family Latridiidae (plaster beetles), described by Poppius in 1903. The species is known from high-latitude regions of the Holarctic, with confirmed records from Yukon Territory, Canada and Alaska, USA. Like other members of Latridiidae, it likely inhabits moist, decaying organic matter. Very few observations exist in public databases.
Corticaria ferruginea
Rusty Spider Beetle
Corticaria ferruginea is a minute beetle in the family Latridiidae, commonly known as spider beetles. The species was described by Marsham in 1802 and is characterized by its small size and ferruginous (rust-colored) appearance. It belongs to a family of beetles typically associated with moist, decaying organic matter and fungal environments. The species has a Holarctic distribution, with records from multiple Canadian provinces.
Corynoptera
fungus gnats
Corynoptera is a genus of fungus gnats in the family Sciaridae, comprising approximately 123 described species in the Holarctic region. The genus has undergone extensive taxonomic revision, with 50 new species described in a 2010 review and numerous nomenclatural changes including restored valid species and new synonymies. Species occur across Europe, Asia, and North America, with records extending to Nepal, Morocco, and Sri Lanka.
Cosmiina
Cosmiina is a subtribe of owlet moths (Noctuidae) within the tribe Xylenini. It comprises multiple genera including Ipimorpha, which contains species with broad geographic distributions spanning Europe, Asia, and North America. Members of this subtribe have been documented in high-altitude wetland habitats in China.
Crabro
Shield-handed Wasps, Square-headed Wasps
Crabro is a genus of solitary wasps in the family Crabronidae, commonly known as shield-handed or square-headed wasps. The genus contains at least 80 described species distributed across the Nearctic and Palaearctic regions (Holarctic). These fossorial wasps nest in sandy soils, constructing multi-celled burrows provisioned with flies (Diptera) for their larvae.
Crangonyx
cave amphipods, spring amphipods
Crangonyx is a genus of freshwater amphipod crustaceans in the family Crangonyctidae. Species inhabit diverse aquatic environments including surface waters (marshes, swamps, lakes, rivers) and subterranean habitats (caves, springs, groundwater systems). The genus includes both native and highly invasive species, with some taxa exhibiting troglobitic adaptations such as reduced eyes and elongated appendages. Several species have been introduced outside their native ranges, notably Crangonyx pseudogracilis and C. floridanus in Europe and Asia, where they interact competitively and predatorily with native amphipods.
Crepidodera
Studded Flea Beetles
Crepidodera is a genus of flea beetles in the family Chrysomelidae, comprising approximately 40 described species worldwide. Members are commonly known as Studded Flea Beetles. They belong to the tribe Alticini and possess the enlarged hind femora characteristic of flea beetles, enabling their distinctive jumping behavior. The genus occurs across the Holarctic region, with species documented in North America, Europe, and Asia.
Criorhinina
Criorhinina is a subtribe of hoverflies (family Syrphidae) within the tribe Milesiini and subfamily Eristalinae. Members are characterized by their association with decaying wood and sap flows, where larvae develop. The subtribe includes genera such as *Criorhina* and *Sphecomyia*, which are often large-bodied and mimic bumble bees or wasps. Adults are primarily found in forested habitats.
Cryphoeca
Cryphoeca is a genus of small araneomorph spiders first described by Tamerlan Thorell in 1870. The genus name derives from Greek meaning "hidden," reflecting its reclusive habits beneath loose bark and within stone walls. The genus contains twelve described species with a Holarctic distribution spanning North America, Europe, and Asia. Cryphoeca species are nocturnal and among the larger members of their subfamily, reaching nearly eight millimeters in body length.
Cryptophagus corticinus
silken fungus beetle
Cryptophagus corticinus is a species of silken fungus beetle in the family Cryptophagidae, first described by C.G. Thomson in 1863. The species has a Holarctic distribution, occurring in both North America and Europe. Members of this genus are generally associated with fungal substrates. Specific ecological details for this species remain poorly documented.
Cryptophagus dentatus
silken fungus beetle
Cryptophagus dentatus is a species of silken fungus beetle in the family Cryptophagidae, first described by Herbst in 1793. The species has a broad geographic distribution spanning the Holarctic region, with confirmed records from Europe, Northern Asia (excluding China), and North America. It has been documented from the Azores (Faial and São Miguel islands). As a member of the silken fungus beetles, it is associated with fungal habitats.
Cryptophagus lapponicus
silken fungus beetle
Cryptophagus lapponicus is a species of silken fungus beetle in the family Cryptophagidae. It has a holarctic distribution, occurring in Europe, Northern Asia (excluding China), and North America. As a member of the Cryptophagidae, it is associated with fungal habitats. The species was described by Gyllenhal in 1827.
Cryptophagus setulosus
silken fungus beetle
Cryptophagus setulosus is a species of silken fungus beetle in the family Cryptophagidae, first described by Sturm in 1845. The species has a Holarctic distribution, occurring in both North America and Europe. As a member of the genus Cryptophagus, it is associated with fungal environments. The species has been documented through 47 iNaturalist observations, indicating it is actively observed but not exceptionally common.
Crypturgini
Crypturgini is a small tribe of bark beetles within the subfamily Scolytinae. These beetles are associated with coniferous trees and are characterized by their minute size and cryptic lifestyle beneath bark. The tribe contains relatively few described species. Members are primarily distributed in the Northern Hemisphere.
Ctenopelmatinae
Ctenopelmatinae is a cosmopolitan subfamily of ichneumonid wasps comprising approximately 95 genera of koinobiont endoparasitoids. Members are small to medium-sized wasps that primarily attack sawflies (Symphyta), with some species parasitizing Lepidoptera. The subfamily was historically classified within Tryphoninae but was separated based on larval morphology and ecological traits. Ctenopelmatines are particularly abundant in temperate Holarctic regions, where they can constitute over 10% of local ichneumonid faunas in cooler areas.
Ctenopelmatini
Ctenopelmatini is a tribe of ichneumonid wasps within the family Ichneumonidae. Members are parasitoid wasps whose larvae develop within or on host organisms. The tribe is characterized by specific morphological traits of the forewing venation and ctenopelmatine-type ovipositor structure. Ctenopelmatini species are primarily associated with sawfly hosts (Symphyta), distinguishing them ecologically from many other ichneumonid tribes. The tribe is relatively small and poorly documented compared to larger ichneumonid tribes.
Cucujus
flat bark beetles
Cucujus is a genus of flat bark beetles in the family Cucujidae, containing approximately 25 recognized species distributed across the Holarctic region. Species are dorso-ventrally compressed, brightly colored in red or red-and-black patterns, and range from 6–25 mm in length. The genus is most diverse in Asia, with indigenous species in North America, Europe, and Asia. Several species, notably C. cinnaberinus and C. clavipes, have been subjects of ecological and physiological research due to their conservation status and extreme cold tolerance adaptations.
Cucullia
Hooded Owlets
Cucullia is a genus of moths in the family Noctuidae, commonly known as Hooded Owlets. The genus was erected by Franz von Paula Schrank in 1802 and contains numerous species distributed across the Holarctic region. Adults are typically nocturnal and attracted to light. Larvae of many species are specialized feeders on plants in the Scrophulariaceae family, particularly Verbascum (mullein), with some species exhibiting conspicuous coloration and diurnal feeding habits.
Culiseta alaskaensis
Alaskan winter mosquito
Culiseta alaskaensis, the Alaskan winter mosquito, is a Holarctic mosquito species adapted to cold subarctic and arctic environments. It has a univoltine life cycle with larvae overwintering and adults emerging in late summer. Females exhibit a distinctive reproductive strategy: they are autogenous for their first egg batch, producing eggs without a blood meal, but require blood for subsequent batches. Adults enter hibernation shortly after emergence without mating or feeding, with mating deferred until spring.
Cychramus
Cychramus is a genus of sap-feeding beetles in the family Nitidulidae, established by Kugelann in 1794. The genus comprises approximately six described species distributed across the Holarctic region. Members of this genus are associated with fermenting plant sap and fungal substrates. They are small beetles typical of the sap beetle guild, though specific ecological details for the genus remain limited.
Cylindrotomidae
long-bodied craneflies
Cylindrotomidae, commonly known as long-bodied craneflies, are a small family of crane flies (Diptera: Tipuloidea) comprising approximately 65–71 extant species in 9 genera and more than 16–20 extinct species. The family represents a classic 'ghost lineage' with no fossil record during the Mesozoic despite diversification of their sister family Tipulidae in the Cretaceous. Crown group diversification began in the Paleogene, with the oldest fossils dating to approximately 56 million years ago. The family is divided into two subfamilies: Cylindrotominae, which are primarily Holarctic in distribution, and Stibadocerinae, which exhibit a Gondwanan distribution with genera restricted to Australia, Chile, and East Asia.
Cyllodes
Cyllodes is a genus of small beetles in the family Nitidulidae, established by Erichson in 1843. The genus comprises approximately 14 described species. Members of this genus are classified as sap-feeding beetles, placing them within the ecological guild of organisms that utilize plant exudates and fermenting materials. The genus belongs to the tribe Cyllodini within the subfamily Nitidulinae.
Cymindis vaporariorum
Cymindis vaporariorum is a species of ground beetle in the subfamily Harpalinae, first described by Carl Linnaeus in 1758. It belongs to the genus Cymindis, a group of predatory beetles within the family Carabidae. Adult activity peaks in June and July, though the species likely remains present throughout the summer months. Its specific epithet 'vaporariorum' suggests a historical association with greenhouses or steamy environments, though the precise origin of the name is not documented in available sources.
Cynaeus depressus
Cynaeus depressus is a species of darkling beetle in the family Tenebrionidae, first described by Horn in 1870. The species is characterized by its dorsoventrally flattened body form, an adaptation that distinguishes it within the genus. Distribution records indicate presence in Mexico, Norway, and Sweden, though the species appears to be rare or poorly collected based on limited observation data. The specific epithet "depressus" refers to this flattened body morphology.
Cynipini
Oak Gall Wasps
Cynipini is the largest tribe of gall wasps in the family Cynipidae, comprising approximately 936 to 1,000 described species. Members are commonly known as oak gall wasps due to their specialized association with oaks (Quercus) and other Fagaceae. The tribe is primarily distributed in the Holarctic region, with significant diversity also in Mexico and Central America. Cynipini species induce structurally diverse galls on various oak tissues including leaves, buds, branches, petioles, catkins, acorns, and roots. Most species exhibit cyclical parthenogenesis, alternating between sexual and asexual generations that often produce different gall morphotypes on the same or different host tissues.
Cyrtoquediina
Cyrtoquediina is a subtribe of rove beetles (Staphylinidae) established by Brunke & Solodovnikov in 2016. It belongs to the tribe Staphylinini within the subfamily Staphylininae. The subtribe contains multiple genera of medium to large-sized rove beetles. Members are distributed across the Holarctic region, with particular diversity in Eurasia.
Dalmanniinae
Dalmanniinae is a subfamily of thick-headed flies (family Conopidae) within the order Diptera. Members of this subfamily are distinguished from other conopids by specific morphological features of the head and wing venation. The subfamily contains genera such as Dalmannia and Zodion, which are primarily found in the Holarctic region. These flies are parasitoids, with larvae developing within the bodies of Hymenoptera hosts.
Damaeidae
Damaeidae is a family of oribatid mites (order Sarcoptiformes) comprising approximately 20 genera distributed across the Northern Hemisphere. Members are primarily fungivorous and inhabit decomposing organic matter including plant litter, mosses, decaying wood, and soil layers. Several species exhibit troglophilic tendencies, occurring in subterranean habitats such as caves and mountain scree systems. The family has undergone extensive taxonomic revision, with historically recognized families Belbidae, Belbodamaeidae, and Hungarobelbidae now synonymized under Damaeidae.
Dasysyrphus intrudens
intrudens complex
Dasysyrphus intrudens is a species complex of hover flies (family Syrphidae) distributed across the Holarctic realm, including North America, Europe, and parts of Asia. The name currently encompasses multiple cryptic species that have not yet been formally delineated. Adults are frequently observed, but larvae remain undescribed as of 2012, possibly due to nocturnal habits.
Deltocephalus pulicaris
Deltocephalus pulicaris is a leafhopper species in the family Cicadellidae, first described by Fallén in 1806. It belongs to the large subfamily Deltocephalinae, which contains many economically significant agricultural pests. The species has been documented across a broad Holarctic distribution spanning Europe, Asia, and North America. Like other members of its genus, it is associated with grassland and meadow habitats.
Dendrophagus
Dendrophagus is a genus of beetles in the family Silvanidae, first described by Schönherr in 1809. The genus contains four recognized species distributed across the Holarctic region. Members of this genus are associated with woody habitats, reflecting their genus name derived from Greek roots meaning "tree-feeding."
Denisia
Denisia is a genus of concealer moths in the family Oecophoridae, subfamily Oecophorinae. Originally described as a subgenus of Borkhausenia by Hübner in 1825, it has since been elevated to generic rank. The genus contains approximately 20 described species distributed primarily across the Holarctic region, with records from Europe, Asia, and North America.
Depressaria
Depressaria is a genus of moths in the family Depressariidae (subfamily Depressariinae), previously treated as part of Oecophoridae or as a distinct family. The genus contains approximately 80+ described species, with new species continuing to be discovered. Most species are specialists on Apiaceae (umbellifers), feeding on reproductive structures, though some species utilize Salicaceae (willows). Several species are economically significant agricultural pests or invasive species in North America, including D. depressana (purple carrot-seed moth) and D. radiella (parsnip webworm). The type species, D. heraclei (parsnip moth), has a confused taxonomic history dating to Linnaeus.
Deretaphrini
Deretaphrini is a tribe of beetles within the family Bothrideridae, a group of Coleoptera commonly known as parasitic flat bark beetles. Members of this tribe are small, often flattened beetles associated with wood-boring insects. The tribe is relatively small and poorly studied compared to other bothriderid groups. Deretaphrini species are presumed to be parasitoids or predators of other insects, particularly beetles developing in dead or decaying wood.
Derodontidae
tooth-necked fungus beetles
Derodontidae is a small family of beetles comprising 42 species in 4 genera and 3 subfamilies. Members are commonly known as tooth-necked fungus beetles due to the spiny pronotal margins found in most genera, though the genus Laricobius lacks these spines. The family is notable for possessing two ocelli on the head, an unusual trait among beetles. The genus Laricobius has gained significant attention as a biological control agent for invasive adelgids threatening hemlock forests in North America.
Derodontus
tooth-necked fungus beetles
Derodontus is a genus of tooth-necked fungus beetles comprising approximately eleven described species. Members are mycophagous, feeding on fungi. The genus has a Holarctic distribution with species recorded from North America, Europe, and Asia. Derodontus macularis has been documented in well-preserved natural forest habitats in eastern Moravia, Czech Republic.