Western-north-america
Guides
Stenodynerus histrionalis
Stenodynerus histrionalis is a solitary mason wasp in the subfamily Eumeninae, native to western North America. The species is difficult to distinguish from similar genera such as Parancistrocerus based on external morphology alone, often requiring microscopic examination of specimens. Females are known to provision nests with paralyzed caterpillars as food for their larvae. Males possess a distinctive antennal modification: the last segment is folded like a finger against the adjacent segment.
Stenodynerus histrionalis paenevagus
Stenodynerus histrionalis paenevagus is a subspecies of solitary mason wasp in the family Vespidae, subfamily Eumeninae. Like other Stenodynerus species, it is a cavity-nesting wasp that provisions its nests with paralyzed caterpillars as food for its larval offspring. The subspecies is difficult to distinguish from related taxa based on field observations alone, and microscopic examination is typically required for definitive identification. It has been documented in Colorado and California, where it utilizes pre-existing cavities in wood or other substrates for nesting.
Stenomorpha cressoni
Stenomorpha cressoni is a species of darkling beetle in the family Tenebrionidae, described by Blaisdell in 1933. It belongs to a genus of elongate beetles found in arid and semi-arid regions of western North America. The species is known from very few observations, with limited published information on its biology. It is one of approximately 30 species currently recognized in the genus Stenomorpha.
Stenomorpha hirsuta
Stenomorpha hirsuta is a species of darkling beetle in the family Tenebrionidae, described by John Lawrence LeConte in 1851. The species epithet 'hirsuta' refers to its notably hairy appearance. It belongs to a genus of relatively small, elongate beetles found in arid and semi-arid regions of western North America. The species is documented through limited iNaturalist observations and museum collections, with sparse published biological information available.
Stenomorpha macra
Stenomorpha macra is a species of darkling beetle in the family Tenebrionidae. It is a small, slender beetle species described by George Henry Horn in 1883. The genus Stenomorpha comprises elongate, parallel-sided beetles found primarily in arid regions of western North America. This species is part of a taxonomically challenging group where species boundaries remain under study.
Stenomorpha muricatula
Stenomorpha muricatula is a species of darkling beetle in the family Tenebrionidae, tribe Asidini. The genus Stenomorpha is large and taxonomically complex, with species distributed across arid and semi-arid regions of western North America, particularly the southwestern United States and Mexico. Members of this genus are generally flightless and associated with rocky or sandy habitats. The specific epithet "muricatula" suggests a rough or spiny surface texture. Like other Stenomorpha species, S. muricatula is likely nocturnal and cryptic in habit, with limited published information on its natural history.
Stenomorpha obsoleta
Stenomorpha obsoleta is a species of darkling beetle in the family Tenebrionidae, first described by LeConte in 1851. The genus Stenomorpha is notably large and taxonomically complex, with modern revisionary work having reduced historically recognized species through synonymization. Like other members of this genus, S. obsoleta is flightless. The species occurs in arid and semi-arid regions of western North America.
Stenomorpha puncticollis
Stenomorpha puncticollis is a species of darkling beetle in the family Tenebrionidae, described by John Lawrence LeConte in 1866. It belongs to the tribe Cteniopodini within the subfamily Stenochiinae. The genus Stenomorpha comprises elongate, parallel-sided beetles distributed primarily in western North America. Observations of this species are relatively sparse, with 51 records documented on iNaturalist.
Stenomorpha quadricollis
Stenomorpha quadricollis is a species of darkling beetle in the family Tenebrionidae, described by Horn in 1880. The genus Stenomorpha comprises elongate, cylindrical beetles found primarily in arid and semi-arid regions of western North America. As a member of this genus, S. quadricollis likely exhibits the slender body form characteristic of the group. Published records for this species are sparse, and detailed biological information remains limited.
Stenomorpha rimata
Stenomorpha rimata is a species of darkling beetle in the family Tenebrionidae, tribe Asidini. The genus Stenomorpha is large and taxonomically complex, historically containing 88 species with limited modern revision until recent work by Fran Keller and colleagues. S. rimata was described by LeConte in 1854. Species in this genus occur in arid and semi-arid regions of western North America and Mexico, with some flightless species restricted to specific mountain ranges.
Stenomorphus californicus rufipes
Stenomorphus californicus rufipes is a subspecies of ground beetle in the family Carabidae. It is one of two recognized subspecies of Stenomorphus californicus, differentiated from the nominate subspecies by its rufous (reddish) legs. The species complex occurs in western North America, with this subspecies recorded from the southwestern United States and Mexico. Like other members of the genus, it is a small, ground-dwelling beetle associated with terrestrial habitats.
Stenopodius lateralis
Lateral Tortoise Beetle
Stenopodius lateralis is a leaf beetle in the family Chrysomelidae, originally described as Brachycoryna lateralis by Schaeffer in 1933. It occurs across western North America from Canada through the United States to Mexico. Adults have been documented on Sphaeralcea species (globemallows), though whether these represent true host plants remains unclear.
Stenostrophia
Stenostrophia is a genus of longhorn beetles (Cerambycidae) in the subfamily Lepturinae, established by Casey in 1913. The genus contains at least three recognized species distributed in western North America. Members are associated with flowering plants in arid and semi-arid habitats. One subspecies, Stenostrophia tribalteata sierrae, has been documented from the Washoe Lake area in Nevada.
Stenostrophia tribalteata serpentina
Stenostrophia tribalteata serpentina is a subspecies of longhorned beetle (family Cerambycidae) in the subfamily Lepturinae. It was described by Casey in 1891. The species Stenostrophia tribalteata is part of a complex with multiple recognized subspecies distributed across western North America.
Stenostrophia tribalteata tribalteata
Stenostrophia tribalteata tribalteata is a subspecies of longhorned beetle (Cerambycidae) in the subfamily Lepturinae. It was originally described by LeConte in 1873. The taxon is currently treated as a synonym in some sources, though it has also been recognized as valid in more recent literature. It occurs in western North America, with records from California and Nevada.
Stenotothorax parapyriformis
Stenotothorax parapyriformis is a species of dung beetle in the family Scarabaeidae, subfamily Aphodiinae. It was described from specimens collected in the western United States. The species name refers to its pear-like (pyriform) body shape, similar to but distinct from related species. It belongs to a genus of small aphodiine dung beetles.
Stenotothorax sparsus
Stenotothorax sparsus is a small scarab beetle in the subfamily Aphodiinae, first described by LeConte in 1878. The species is documented from limited localities in western North America, including California, Oregon, and Chihuahua, Mexico. Records remain sparse, with only seven observations documented on iNaturalist. As a member of the Aphodiinae, it likely occupies dung-associated habitats, though specific ecological details remain poorly documented.
Stenus sculptilis
Stenus sculptilis is a species of rove beetle in the subfamily Steninae, described by Casey in 1884. It occurs in western North America, with records from British Columbia, Canada, and several western US states including California, Idaho, Nevada, Oregon, and Washington. As a member of the genus Stenus, it belongs to a group known for specialized predatory adaptations, though specific biological details for this species remain poorly documented.
Sternidius wiltii
Sternidius wiltii is a small longhorned beetle (Cerambycidae: Lamiinae: Acanthocinini) native to western North America. The genus Sternidius has undergone taxonomic revision, with species previously synonymized under S. alpha later revalidated. Specimens are typically collected by beating branches of woody vegetation. The species is small enough to require pointing rather than direct pinning for proper curation.
Stethophyma gracilis
Graceful Grasshopper
Stethophyma gracilis is a grasshopper species in the subfamily Gomphocerinae, native to western North America. It inhabits moist meadows and grasslands, particularly in montane and subalpine regions. The species is characterized by its slender body form and relatively long wings. Populations are typically found at higher elevations compared to many other grasshopper species in the region.
Sticthippus californicus
fastigial range grasshopper
Sticthippus californicus, commonly known as the fastigial range grasshopper, is a species of band-winged grasshopper in the family Acrididae. It was first described by Scudder in 1892. The species belongs to the subfamily Oedipodinae, which are characterized by their banded wings. It is found in western North America, with confirmed records from California.
Stictopleurus plutonius
Stictopleurus plutonius is a species of true bug in the family Rhopalidae, described by Baker in 1908. It belongs to a genus of scentless plant bugs found in temperate regions. Records indicate it occurs in western North America, specifically in British Columbia. Very few observations exist, with only two records documented on iNaturalist.
Stigmatomma oregonense
Western Dracula Ant
Stigmatomma oregonense is a species of Dracula ant in the subfamily Amblyoponinae, native to western North America. It is a specialized predator known to hunt centipedes. The species was first described by Wheeler in 1915 and has been maintained in live colonies for public display and research. Like other members of its genus, it exhibits predatory behaviors characteristic of the Amblyoponinae.
Stigmella undescribed-species-on-frangula-purshiana
An undescribed species of pygmy moth in the genus Stigmella (family Nepticulidae) associated with Frangula purshiana (cascara buckthorn). As a member of this genus, it is a leaf-mining moth whose larvae feed internally within leaf tissue. The species has not yet received formal scientific description, though its host plant association has been documented. Stigmella species are typically small, with adults often measuring less than 5 mm in wingspan, and are recognized by their distinctive larval feeding patterns.
Stizoides
Stizoides is a genus of kleptoparasitic sand wasps in the family Crabronidae, containing approximately 30 described species globally. The genus is notable for its unique parasitic strategy: females exploit the food caches of other solitary wasps rather than hunting their own prey. Two species occur in North America—S. renicinctus (widespread in western North America) and S. foxi (restricted to Arizona and Mexico). Most species are found in Africa, Mediterranean Europe, the Middle East, and India.
Stizoides renicinctus
Stizoides renicinctus is a kleptoparasitic sand wasp in the family Crabronidae, one of only two species in its genus occurring in North America. The species has no common English name. It is known for its distinctive black body with a red or orange band on the second abdominal tergite, dark wings with translucent tips, and elongate build. Males are frequently observed visiting flowers for nectar, while females actively seek out the burrows of host wasps to exploit their food stores. The species exhibits unusual social behaviors including nighttime sleeping clusters and weather-related aggregations.
Stobaera giffardi
Stobaera giffardi is a species of planthopper in the family Delphacidae, described by Van Duzee in 1917. It belongs to a genus of small, slender delphacid planthoppers found in North America. The species is known from California and represents one of several Stobaera species distributed in western North America. Like other delphacids, it likely inhabits grassland and wetland habitats associated with its host plants.
Stomis termitiformis
Stomis termitiformis is a species of ground beetle in the family Carabidae, described by Van Dyke in 1926. The specific epithet "termitiformis" suggests a resemblance to termites in form or habit. It is recorded from the western United States and British Columbia, Canada.
Stratiomys maculosa
spotted soldier fly
Stratiomys maculosa is a species of soldier fly in the family Stratiomyidae, commonly known as the spotted soldier fly. It is native to western North America, with documented occurrence from British Columbia through California and inland to Utah, Idaho, and Nevada. The species is associated with riparian habitats and is known to visit flowers.
Styracosceles
New Mexico camel cricket
Styracosceles is a genus of camel crickets in the family Rhaphidophoridae, established by Hubbell in 1936. The genus contains at least four described species distributed in western North America, including the New Mexico camel cricket (Styracosceles neomexicanus). These crickets are part of the subfamily Ceuthophilinae and are found in arid and semi-arid habitats.
Subhaida ingrata
Subhaida ingrata is a species of rove beetle in the family Staphylinidae, originally described as Pseudohaida ingrata by Hatch in 1957. The species belongs to the subfamily Omaliinae and tribe Coryphiini. It has been documented from western North America, including the Pacific coast and adjacent interior regions.
Sunira verberata
Battered Sallow
Sunira verberata is a noctuid moth of western North America, previously classified under Agrochola. Adults are active in late summer and fall. The species occupies montane and boreal forest habitats across a broad latitudinal range from Alaska to the southwestern United States.
Svastra obliqua expurgata
sunflower bee, long-horned digger bee, female long-horned bee
Svastra obliqua expurgata is a subspecies of long-horned bee in the family Apidae, native to western North America. It is commonly known as the 'sunflower bee' due to its strong preference for foraging on sunflowers and other members of the Asteraceae family. The species has been reclassified taxonomically, with some authorities placing North American species formerly in genus Svastra into the genus Epimelissodes. It is a solitary, ground-nesting bee that plays an important role in pollinating native and agricultural plants in its range.
Sweltsa coloradensis
Colorado Sallfly
Sweltsa coloradensis, known as the Colorado sallfly, is a green stonefly species in the family Chloroperlidae. It is found in western North America, with records from Alaska, Alberta, British Columbia, California, and Arizona. Like other members of its family, it likely inhabits cold, clean streams. The species was described by Nathan Banks in 1898.
Symmorphus projectus
Symmorphus projectus is a small, slender mason wasp in the subfamily Eumeninae. It is strictly western in distribution, ranging from the Pacific Northwest to Montana, Wyoming, and southward. Females nest in pre-existing cavities such as beetle borings in dead wood, provisioning cells with paralyzed leaf beetle larvae, weevil larvae, or leaf-mining moth caterpillars for their offspring. The species is one of four Symmorphus species in North America and can be distinguished from eastern congeners by geographic range and subtle morphological features.
Sympetrum madidum
red-veined meadowhawk
Sympetrum madidum, the red-veined meadowhawk, is a medium-sized dragonfly in the family Libellulidae. It is distinguished from congeners by gold to red clouding of its wings and red wing veins. The species ranges across western and northern North America, inhabiting shallow marshy ponds and lakes. Adults are active from mid-June to mid-September, with some populations flying from April through September.
Sympistis acheron
Sympistis acheron is a noctuid moth species described by James T. Troubridge in 2008. It occurs in montane regions of western North America at elevations between 600 and 3,000 meters. Adults are active from late July through late September.
Sympistis anweileri
Sympistis anweileri is a noctuid moth described from western North America in 2008. It occurs at moderate to high elevations (2,000–8,000 feet) in mountainous terrain from Alberta and British Columbia south to Montana. The species inhabits a range of habitats from alpine treeline to dry valley forests. Adults fly in mid-summer with a wingspan of 30–36 mm.
Sympistis chalybdis
Sympistis chalybdis is a noctuid moth species described in 1999 from western North America. It belongs to the diverse genus Sympistis, which contains numerous cryptic species often distinguished by subtle genitalic differences. The species is known from a limited number of records, reflecting both its relatively recent description and likely restricted range.
Sympistis cherti
Sympistis cherti is a noctuid moth species described by James T. Troubridge in 2008. It is a relatively recently described species with a restricted distribution in montane western North America. Adults are active during mid-summer at moderate to high elevations. The species is known from very few observations.
Sympistis columbia
Sympistis columbia is a noctuid moth described by James Halliday McDunnough in 1922. The species was transferred from the genus Oncocnemis to Sympistis in 2008 based on phylogenetic revision. It is known from a limited number of observations in western North America, with confirmed records in British Columbia, Canada.
Sympistis glennyi
Sympistis glennyi is a noctuid moth described by Augustus Radcliffe Grote in 1873. It is a small moth with a wingspan of approximately 35 mm, distributed across mountainous regions of western North America. The species was formerly placed in the genus Oncocnemis before reclassification to Sympistis.
Sympistis greyi
Sympistis greyi is a noctuid moth described from western North America in 1998. The species is named for L. Paul Grey. It is known from a relatively narrow geographic range spanning British Columbia through central Washington and Oregon. The wingspan measures approximately 30 mm, with forewings 12–14 mm in length.
Synanthedon bibionipennis
Strawberry Crown Moth
Synanthedon bibionipennis is a clearwing moth in the family Sesiidae, commonly known as the strawberry crown moth. Adults are active from April to August and are diurnal. The species has one generation per year. Larvae are borers that feed internally on the crowns and roots of various rosaceous plants.
Synanthedon resplendens
Sycamore Borer Moth
A clearwing moth (family Sesiidae) native to western North America. Adults exhibit wasp-mimicry with yellow and black coloration and transparent wings. Larvae are bark miners, primarily infesting sycamore and oak trees. Despite extensive tunneling, damage is generally considered minor and trees tolerate infestation well.
Synchlora graefiaria
Synchlora graefiaria is a species of emerald moth in the family Geometridae, first described by Hulst in 1886. Like other members of the genus Synchlora, its caterpillars are known for their remarkable camouflage behavior, adorning their bodies with bits of plant material from their host plants to blend into their surroundings. The species is found in North America, though specific details about its range and biology remain limited in available literature.
Syneta albida
western fruit beetle
A small leaf beetle in the subfamily Synetinae, found in western North America. Adults feed on foliage of deciduous fruit trees and ornamentals, while larvae develop in soil feeding on roots. The species is considered a minor pest of orchards and gardens.
Syneta hamata
Syneta hamata is a species of leaf beetle in the family Chrysomelidae. It was described by Horn in 1893. The species occurs in western North America, with records from western Canadian provinces including Alberta, British Columbia, and Manitoba.
Synetocephalus
Synetocephalus is a genus of skeletonizing leaf beetles in the family Chrysomelidae, containing approximately 10 described species. The genus was established by Fall in 1910 and is restricted to North America. Species in this genus are small leaf-feeding beetles that skeletonize plant foliage. One species, Synetocephalus penrosei, was described in 2012 from California and named in honor of the coleopterist Richard L. Penrose.
Syngrapha angulidens
Syngrapha angulidens is a noctuid moth described by Smith in 1891. It is distributed across montane regions of western North America from Alaska to New Mexico. The species has a single annual generation with adults active in mid-summer.