Palearctic
Guides
Silpha tristis
Silpha tristis is a carrion beetle species first described by Illiger in 1798. It belongs to the family Silphidae, a group associated with decomposition and carrion feeding. The species has a broad distribution across the Palearctic region and has been introduced to North America.
Silusa
Silusa is a genus of rove beetles (Staphylinidae: Aleocharinae: Homalotini) established by Erichson in 1837. The genus occurs in the Nearctic and Palearctic regions, with species documented in Europe and North America. Nearctic species have been subject to recent taxonomic revision, which expanded known distributions and clarified species boundaries through examination of external and genital morphology.
Simitidion simile
Simitidion simile is a species of comb-footed spider in the family Theridiidae. Native to the Palearctic region, it has been documented across Europe, North Africa, Turkey, Israel, the Caucasus, Kazakhstan, Iran, and Central Asia. The species has been introduced to Canada, establishing populations outside its native range. As a member of the Theridiidae, it possesses the characteristic comb-like setae on the hind tarsi used for silk handling.
Simplocaria semistriata
pill beetle
Simplocaria semistriata is a species of pill beetle in the family Byrrhidae, first described by Fabricius in 1794. It is one of approximately 30 species in the genus Simplocaria. The species has been recorded across a broad geographic range spanning Europe, Northern Asia (excluding China), and North America. Pill beetles in this family are known for their ability to conglobate—roll into a ball—and often inhabit moist, mossy environments.
Singa
striped orb-weavers
Singa is a genus of small orb-weaver spiders in the family Araneidae, commonly known as striped orb-weavers. First described by C. L. Koch in 1836, these spiders are diminutive for orb-weavers, with body lengths typically not exceeding 6 millimetres. The genus is characterized by its distinctive striped patterning and classic orb-web construction.
Sinoxylon ceratoniae
horned powder-post beetle
Sinoxylon ceratoniae is a species of horned powder-post beetle in the family Bostrichidae. It is distributed across Africa, Europe, and Northern Asia (excluding China). The species belongs to a group of wood-boring beetles known for their ability to damage seasoned timber and wooden products. As a member of the genus Sinoxylon, it possesses characteristic horn-like projections on the pronotum.
Sironidae
Sironid Harvestmen
Sironidae is a family of Cyphophthalmi harvestmen comprising more than 60 described species. It was the first described family of the suborder Cyphophthalmi and remains among the least understood phylogenetically. The family exhibits a predominantly Laurasian distribution, with species concentrated in temperate Europe and the west coast of North America. Monophyly of the family is poorly supported with traditional molecular markers; the Mediterranean genus Parasiro and Japanese genus Suzukielus sometimes branch basally relative to other sironids.
Smaragdina
Smaragdina is a genus of short-horned leaf beetles in the family Chrysomelidae, subfamily Clytrinae. These beetles are characterized by their compact body form and association with vegetation. The genus occurs primarily in the Palearctic region, with documented records from Denmark, Norway, and Sweden. As leaf beetles, species in this genus are herbivorous, though specific host plant associations vary among species.
Smidtia
Smidtia is a genus of tachinid flies established by Robineau-Desvoidy in 1830. The genus comprises approximately 22 described species distributed across the Palearctic region, with particularly strong representation in East Asia, Europe, and southern Africa. Species have been documented from Scandinavia, Russia, Japan, China, and South Africa. As members of the tribe Winthemiini, these flies are parasitoids, though specific host associations remain poorly documented for most species.
Sorhagenia
Sorhagenia is a genus of small moths in the family Cosmopterigidae, established by Spuler in 1910. The genus name honors Ludwig Friedrich Sorhagen, a German entomologist. It comprises approximately 16 described species distributed primarily across the Palearctic region, with some species also recorded from North America. The genus is taxonomically well-established within the superfamily Gelechioidea, though individual species remain poorly known in terms of their biology and ecology.
Sphaeridium marginatum
Sphaeridium marginatum is a species of water scavenger beetle in the family Hydrophilidae, first described by Fabricius in 1787. It belongs to the subfamily Sphaeridiinae, a group commonly known as dung beetles within the Hydrophilidae. The species has a broad Palearctic distribution across Europe, North Africa, and parts of Asia, with introduced populations reported in North America. It is associated with decaying organic matter and moist habitats.
Sphragisticus nebulosus
dirt-colored seed bug
Sphragisticus nebulosus is a species of true bug in the family Rhyparochromidae, commonly known as dirt-colored seed bugs. It has a broad distribution spanning North America, Europe, and Asia. The species was first described by Fallén in 1807 under the name Lygaeus nebulosus. Like other members of its family, it is associated with seeds and ground-level vegetation.
Spilonota ocellana
bud moth, eye-spotted bud moth
Spilonota ocellana, commonly known as the bud moth or eye-spotted bud moth, is a small tortricid moth with a wingspan of 12–17 mm. It has a wide distribution spanning the Palearctic realm from North Africa and Europe through Asia to China, Korea, and Japan, with introduced populations in North America and Madeira. The species is univoltine, with adults flying from May to October depending on location. Larvae feed on various deciduous trees and shrubs, and the species is recognized as a pest in apple orchards where it has been studied extensively.
Spiracme
Spiracme is a genus of crab spiders in the family Thomisidae, erected by Anton Menge in 1876. The genus has undergone extensive taxonomic revision, with species frequently transferred between it and related genera Xysticus and Ozyptila. A 2019 DNA barcoding study by Rainer Breitling helped clarify relationships among these genera. As of January 2026, the genus comprises ten species, including S. striata (the type species) and S. mongolica, which was transferred from Xysticus and represents the first Central European record for the genus.
Steatoda castanea
Steatoda castanea is a cobweb spider in the family Theridiidae, closely related to black widows and other Steatoda species. It is native to the Palearctic region, with distribution records from Europe through Russia, the Caucasus, Iran, Central Asia, and China. The species has been introduced to North America, including Canada. As a member of the cobweb weaver family, it constructs irregular tangled webs and shares the general morphology and habits typical of the genus Steatoda, though specific behavioral and ecological details for this species remain poorly documented in available literature.
Stemonyphantes
Stemonyphantes is a genus of sheet-weaving spiders in the family Linyphiidae, first described by Anton Menge in 1866. The genus comprises approximately 20 species distributed across the Palearctic region, with some species extending into North America. As members of Linyphiidae, they construct flat, horizontal sheet webs for prey capture. The type species, Stemonyphantes lineatus (Linnaeus, 1758), is widespread across Europe and into Central Asia.
Stenacidia violacea
Stenacidia violacea is a springtail species in the family Sminthurididae, characterized by distinctive coloration with yellowish body and purple lateral markings. The species exhibits sexual dimorphism in coloration, with females sometimes appearing dark purple. A notable behavioral trait involves antenna contact during mating, described as resembling a 'kiss'. The species has a broad distribution spanning the Nearctic and Palearctic regions, with a recent range extension to Iran documented in 2019.
Stenodema
grass bugs
Stenodema is a genus of plant bugs in the family Miridae, tribe Stenodemini, distributed across the Palearctic, Oriental, and Nearctic regions. Species are commonly known as grass bugs due to their association with graminoid monocots. The genus includes both trans-Palearctic and trans-Holarctic species, with some exhibiting wide geographic ranges and potential cryptic diversity. Stenodema species have been studied using integrative taxonomic approaches combining morphological examination of genitalia with molecular phylogenetics.
Stenolophus
Seedcorn Beetles
Stenolophus is a large genus of ground beetles in the family Carabidae, comprising over 190 described species distributed across the Palearctic, Nearctic, Near East, and North Africa. Commonly known as seedcorn beetles, several species are significant agricultural pests of corn and other crops. The genus includes both univoltine and potentially multivoltine species depending on geographic location.
Stenus clavicornis
Stenus clavicornis is a species of rove beetle in the family Staphylinidae, subfamily Steninae. Like other members of the genus Stenus, this species possesses the ability to glide on water surfaces using specialized gland secretions that reduce surface tension. The species has been recorded across a broad Palearctic distribution and has been introduced to parts of North America.
Stenus plicipennis
Stenus plicipennis is a species of rove beetle in the subfamily Steninae, described by Casey in 1884. Like other members of the genus Stenus, it possesses the characteristic labial apparatus used for prey capture, though the specific ecology of this species remains poorly documented. The species has a Holarctic distribution, occurring across northern North America and eastern Russia. It represents one of numerous Stenus species adapted to moist microhabitats where predatory specialization on small invertebrates occurs.
Stephensia
Stephensia is a genus of moths in the family Elachistidae, a group of small, often inconspicuous microlepidoptera. The genus name has been used for multiple taxa across kingdoms, including a genus of fungi (Pyronemataceae) and historically as a synonym for a tachinid fly genus (Microsoma), but in entomological contexts refers primarily to the moth genus. The genus contains multiple described species distributed primarily in the Palearctic region.
Stigmella anomalella
rose leaf miner
Stigmella anomalella is a microlepidopteran moth in the family Nepticulidae, commonly known as the rose leaf miner. Adults are active from May to August with two generations per year. The larvae are leaf miners that feed on various Rosa species and related plants in the Rosaceae family, creating distinctive corridor mines with hairpin turns in host leaves.
Stilpon
Stilpon is a genus of small predatory flies in the family Hybotidae, subfamily Tachydromiinae. The Nearctic fauna comprises 13 recognized species, including nine described by Cumming (1992), classified into three informal species groups: S. divergens, S. graminum, and S. varipes. The genus exhibits wing polymorphy in some species, with both macropterous and micropterous forms documented in S. graminum, S. nubilus, and S. subnubilus.
Streptanus okaensis
Streptanus okaensis is a species of leafhopper in the family Cicadellidae, subfamily Deltocephalinae. First described by Zakhvatkin in 1948, it is currently treated as a synonym of Streptanus ogumae. The species has been recorded from localities across the northern Palearctic, including Alaska, England, Kamchatka, and the Kuril Islands.
Stygobromus
Stygobromus is a genus of subterranean freshwater amphipods in the family Crangonyctidae, comprising 134 described species. The genus is primarily distributed in North America, with a smaller number of species in the Palearctic region including Siberia. Many species are narrow endemics restricted to specific groundwater systems, and several are listed as endangered or vulnerable by the IUCN; one species, S. lucifugus, is extinct.
Styphlini
Styphlini is a tribe of weevils within the family Curculionidae, subfamily Curculioninae. The tribe includes genera such as Styphlus and Orthochaetes. Species within this tribe show Palearctic affinities, with some taxa documented from the eastern Mediterranean, southern France, Mallorca, and more recently from North America as introduced or expanding populations.
Suillia variegata
Suillia variegata is a Palearctic species of heleomyzid fly distributed throughout Britain and Ireland, with highest occurrence in England and Wales. The species exhibits a mixed feeding strategy, primarily mycophagous but also associated with decaying flowers, roots, and bird's nests. Adults display an earthy brown thorax with sparse hairs and a pale striped abdomen, with distinctive wing spines useful for identification. The species peaks in density during April/May and July/August.
Sunius melanocephalus
Sunius melanocephalus is a species of rove beetle in the family Staphylinidae, subfamily Paederinae. It is native to the Palearctic region with a broad distribution across Europe, Russia, the Caucasus, and Central Asia. The species has been introduced to North America, where it is established in parts of Canada and the northeastern United States.
Swammerdamia
Swammerdamia is a genus of small moths in the family Yponomeutidae, established by Hübner in 1825. The genus contains approximately 13 described species distributed across the Palearctic, Afrotropical, and Nearctic regions. Species are associated with various host plants, including Rosaceae. The genus is named in honor of the Dutch naturalist Jan Swammerdam.
Sylvicola fenestralis
Window Gnat
Sylvicola fenestralis, commonly known as the window gnat, is a medium-sized dipteran in the family Anisopodidae. Adults measure 6–10 mm in length. The species is distributed across the Palearctic region, with records from Scandinavia and other parts of Europe. It is one of approximately 40 species in the genus Sylvicola.
Sylvicola punctatus
Sylvicola punctatus is a species of wood gnat in the family Anisopodidae, a group of small to medium-sized flies characterized by their distinctive wing venation. The species is distributed across the Palearctic region, with documented records from northern Europe including Belgium, Denmark, Norway, and Sweden. Like other members of the genus Sylvicola, adults are typically found in wooded or forested habitats where their larvae develop in decaying organic matter.
Synchroa
synchroa bark beetles
Synchroa is a genus of beetles in the family Synchroidae, comprising approximately six described species. Members are characterized by an elongate, tapered, and slightly flattened body with brownish to black coloration. The genus represents the nominal and largest genus within its family, with a broad distribution spanning North America, the eastern Palearctic, and the Oriental regions. Species diversity is highest in Eastern Asia, where multiple new species have been described in recent decades.
Synthesiomyia
Synthesiomyia is a small genus of muscid flies in the family Muscidae. The genus contains at least one well-documented species, Synthesiomyia nudiseta, which has gained forensic importance as a carrion-associated fly in tropical, subtropical, and recently colonized Palearctic regions. Species in this genus exhibit facultative predatory behavior and are used in postmortem interval estimation.
Syntomus
Syntomus is a genus of ground beetles in the family Carabidae, subfamily Lebiinae. The genus contains at least 50 described species distributed across the Palearctic region and North America. Members are small to minute beetles, with at least one species (Syntomus lateralis) documented as a host for parasitic mites in the family Podapolipidae.
Syricoris
Syricoris is a genus of tortrix moths established by Treitschke in 1829, comprising approximately six recognized species. The genus belongs to the subfamily Olethreutinae and is taxonomically closely related to Celypha, with which it has sometimes been merged. Species in this genus are small moths with distributions primarily across the Palearctic region. The genus includes several widespread species such as Syricoris lacunana and Syricoris rivulana.
Syricoris lacunana
Dark strawberry tortrix, Common Marble
Syricoris lacunana is a small tortricid moth with a wingspan of 16–18 mm, found throughout the Palearctic realm. Adults are active at dusk from late April to September, with variable gray-brown forewings marked by thin silvery lines. The species is highly polyphagous, with larvae feeding on a broad range of herbaceous plants, shrubs, and trees. It is commonly encountered in hedgerows, fields, and woodland edges across Europe and northern Asia.
Taenionema
winter stoneflies
Taenionema is a genus of winter stoneflies (Plecoptera: Taeniopterygidae) comprising approximately 14 described species. The genus was established by Banks in 1905 with Taenionema analis as the type species. Species are distributed across the Nearctic and eastern Palearctic regions, with 13 species native to North America and one species (T. japonicum) ranging across Japan, Korea, Mongolia, Russia and northeastern China. A second Eastern Hemisphere species, T. sinensis, was described in 2023 from southeastern China.
Talavera
Talavera is a genus of minute jumping spiders (Salticidae) established by George and Elizabeth Peckham in 1909. These spiders are exceptionally small, averaging approximately 2 mm in body length, and exhibit remarkable morphological similarity among species—particularly within Central European populations, where identification often requires microscopic examination of genital structures. The genus name commemorates Talavera, Spain, a region where numerous specimens have been collected. The group represents one of several genera of diminutive salticids that challenge taxonomic distinction due to conserved external morphology.
Tanypezidae
Stretched-foot Flies
Tanypezidae is a small family of acalyptrate Diptera containing 28 species in two genera. The family is primarily New World in distribution, with Tanypeza (2 species) occurring in North America and the Palearctic, and Neotanypeza (26 species) restricted to the Neotropics. Species are characterized by their relatively large size, semispherical heads, stout bodies, and notably long, thin legs that give the family its common name. The biology of most species remains poorly known.
Tanytarsus
non-biting midge
Tanytarsus is a large genus of non-biting midges comprising over 480 described species. The genus belongs to the tribe Tanytarsini within the subfamily Chironominae. Larvae occur in diverse freshwater habitats, with some species inhabiting marine environments. Species-level studies reveal complex life cycles with photoperiod and temperature as key determinants of seasonal patterns.
Tapinocyba
sheet weavers
Tapinocyba is a genus of sheet web spiders (family Linyphiidae) established by Eugène Louis Simon in 1884. The genus comprises approximately 40 species distributed across the Nearctic and Palearctic regions, including Europe, Asia, North America, and North Africa. Species are primarily found in leaf litter and forest floor habitats, often at montane elevations. Recent taxonomic work has clarified species boundaries and described new species from previously undersampled regions such as China and Nepal.
Telmatophilus
Telmatophilus is a genus of silken fungus beetles (family Cryptophagidae) established by Heer in 1841. The genus comprises approximately seven described species distributed across Europe and North America. These beetles are associated with moist, decomposing plant matter, particularly in wetland and riparian habitats. The type species, Telmatophilus typhae, was described by Fallén in 1802 from cattail (Typha) habitats.
Teloleuca
Teloleuca is a genus of shore bugs in the family Saldidae, established by Reuter in 1912. The genus comprises approximately five described species. Members of this genus are true bugs (Hemiptera: Heteroptera) within the infraorder Leptopodomorpha. Shore bugs in this family are generally associated with moist habitats near water bodies.
Telomerina
Telomerina is a genus of small flies in the family Sphaeroceridae, commonly known as lesser dung flies. The genus was established by Roháček in 1983 and contains approximately 15 described species. Species have been recorded from northern Europe including Denmark, Norway, and Sweden. The genus belongs to the subfamily Limosininae within the sphaerocerid flies.
Temnostethus
minute pirate bugs
Temnostethus is a genus of minute pirate bugs in the family Anthocoridae, established by Fieber in 1860. The genus comprises approximately eight described extant species plus one fossil species from the Oligocene. Members of this genus are small predatory true bugs found primarily in the Palearctic region.
Tenuiphantes
Tenuiphantes is a genus of sheet-weaving spiders (family Linyphiidae) comprising 44 described species as of 2019. The genus was established by Saaristo and Tanasevitch in 1996 to accommodate species previously placed in other genera, particularly within the Lepthyphantes complex. Species occur across diverse habitats in the Northern Hemisphere and have been introduced to multiple Southern Hemisphere locations, including New Zealand, Chile, and Argentina.
Tephritis
Tephritis is a large genus of true fruit flies (Diptera: Tephritidae) comprising approximately 170 described species, making it the sixth largest genus in the family. Species occur across diverse climate zones from hot semidesert to tundra, with the greatest diversity in the Palearctic region. Most species are associated with Asteraceae plants, inhabiting inflorescences of several tribes including Cardueae, Cichorieae, Anthemideae, Inuleae, and Senecioneae. Some species cause gall formation on host plants. The genus has been extensively studied for host-race formation and incipient speciation, particularly in T. conura and T. bardanae, which show genetic and morphological differentiation correlated with host-plant use.
Tephrochlamys rufiventris
Tephrochlamys rufiventris is a small fly in the family Heleomyzidae, measuring 5–6 mm in body length. It is distributed across the Palearctic region, with records from Scandinavia, Denmark, Sweden, Norway, and Madeira Island. The species is characterized by distinctive thoracic setal arrangements and wing venation features useful for identification.
Terellia
Terellia is a genus of fruit flies in the family Tephritidae, comprising approximately 60 described species distributed across the Palearctic region. Species in this genus are primarily associated with thistles and related plants in the Asteraceae family, with larvae developing in flower heads (capitula) of their host plants. The genus includes several species groups (virens group, amberboae group, tarbinskiorum group) distinguished by morphological characters and host associations. Terellia ruficauda has been used as a biological control agent for Canada thistle.