Endemic
Guides
Arta brevivalvalis
Arta brevivalvalis is a species of pyralid moth endemic to Arizona, United States. It was described by Cashatt in 2012. The species is characterized by distinctive wing coloration: forewings are reddish brown to purplish brown with ochreous antemedial and postmedial lines, while the hindwings are greyish brown.
Artemia monica
Mono Lake brine shrimp
Artemia monica is a brine shrimp species endemic to Mono Lake, California. It is a sibling species of the widespread A. franciscana, with which it is reproductively isolated due to different water requirements. The species exhibits strong salinity-dependent life history traits, with higher salinities reducing hatching success, survival, growth, and reproductive output while prolonging developmental timelines.
Aseptis murina
Aseptis murina is a noctuid moth described by Tomas Mustelin in 2000. The species name refers to its smooth, mouse-like appearance. It is restricted to southern California, where it occupies a range of habitats from coastal chaparral to oak forest and mountain-desert transition zones at elevations up to 2000 meters. Adults are active from early May through July.
Aseptis perfumosa
Aseptis perfumosa is a noctuid moth endemic to southern California, first described by George Hampson in 1918. It occupies diverse habitats from sea level to 2000 meters elevation, including coastal chaparral, canyons, urban areas, brush land, and open oak forest. The species is univoltine, with adults active from early April to early June at lower elevations and slightly later at higher elevations. Larvae feed on species of Arctostaphylos.
Athoplastus rainieri
Athoplastus rainieri is a click beetle (family Elateridae) endemic to the Cascade Range of Washington State. Originally described by Van Dyke in 1932, it was transferred to the genus Athoplastus by Etzler & Johnson in 2018. The species is known from very few specimens and remains poorly documented in the scientific literature.
Atrytonopsis quinteri
Crystal Skipper
Atrytonopsis quinteri, the Crystal Skipper, is a recently described skipper butterfly (family Hesperiidae) endemic to a narrow coastal range in North Carolina. The species was formally described in 2015 by Burns, though specimens had been collected as early as 1978. Its extremely restricted distribution along barrier islands makes it one of the most geographically limited butterfly species in North America.
Attalus frosti
Attalus frosti is a species of soft-winged flower beetle in the family Melyridae. The species is known from very few specimens in Missouri, with records from Lichen Glade Natural Area in St. Clair County and a single specimen collected in a malaise trap in central Missouri. It is associated with post oak (Quercus stellata) in dry sandstone woodland habitats. The species appears to be rare and poorly known, with no records since the original collections.
Austrotyla stephensoni
Austrotyla stephensoni is a species of millipede in the family Conotylidae, described by Shear & Steinmann in 2013. It belongs to the order Chordeumatida, a group of small to medium-sized millipedes commonly known as silk-spinning or short-back millipedes. The genus Austrotyla is endemic to the southern Appalachian region of the United States. This species appears to be rare and poorly known, with limited observational records.
Autographa corusca
Caramel Looper
Autographa corusca is a noctuid moth endemic to the Pacific Northwest coastal forests. Adults have a wingspan of approximately 33 mm and are active in midsummer. Larvae feed on alder species (Alnus).
Bagisara brouana
Bagisara brouana is a noctuid moth described by A.D.C. Ferguson in 1997. It is known from only two US states—Louisiana and Mississippi—representing one of the most geographically restricted species in the genus. Its extremely limited range has been hypothesized to reflect specialized larval host plant associations, potentially to a single plant genus or species with similarly restricted distribution. The species belongs to the subfamily Bagisarinae, a small New World group whose biology remains poorly documented.
Banksula
Banksula is a genus of harvestmen in the family Phalangodidae, comprising ten described species. All species are endemic to California, United States. The genus was established by Roewer in 1949 and named in honor of Nathan Banks, an American entomologist who described the type species. These harvestmen belong to the suborder Laniatores, a diverse group of short-legged, often heavily armored opilionids.
Battus philenor hirsuta
California pipevine swallowtail, hairy pipevine swallowtail
A California endemic subspecies of pipevine swallowtail distinguished by smaller size, denser body hair, and larger egg clutches than the nominate subspecies. Adults display iridescent green-blue hindwings with red ventral spots, while larvae are black with fleshy protrusions and orange markings. The subspecies maintains a tightly coupled relationship with its sole host plant, Aristolochia californica, sequestering toxic aristolochic acids for chemical defense. Unlike other Battus philenor populations, this subspecies has no known Batesian mimics.
Beameromyia monticola
Santa Rita Pixie
Beameromyia monticola is a species of robber fly in the family Asilidae, described by Martin in 1957. The species epithet 'monticola' (mountain-dwelling) suggests an association with montane habitats. The common name 'Santa Rita Pixie' indicates a likely connection to the Santa Rita Mountains of Arizona. As a member of the Asilidae, it belongs to a family of predatory flies known for their aggressive hunting behavior and distinctive morphology.
Belocephalus
short-winged coneheads
Belocephalus is a genus of short-winged conehead katydids comprising approximately eight described species. Members of this genus are characterized by abbreviated wing development and are endemic to the southeastern United States. The genus was established by Scudder in 1875 and belongs to the tribe Copiphorini within the subfamily Conocephalinae.
Belonocnema
Belonocnema is a genus of cynipid gall wasps restricted to the southeastern United States. The genus comprises three recognized species that induce distinct galls on section Virentes oaks, including live oaks. All species exhibit heterogony, with alternating sexual and asexual generations producing morphologically and ecologically different gall types. The genus has been subject to taxonomic revision, with Dryorhizoxenus now synonymized under Belonocnema.
Berninelsonius hyperboreus
Beringian Click Beetle
Berninelsonius hyperboreus is a click beetle (family Elateridae) endemic to the Beringian region of the Arctic. The species was described by Gyllenhal in 1827 and represents one of the few elaterid beetles adapted to extreme northern environments. It is known from a very small number of observations and collections, reflecting both its restricted range and the difficulty of accessing its habitat. The genus Berninelsonius is monotypic, containing only this species.
Bishopella
Bishopella is a genus of harvestmen (Opiliones) in the family Phalangodidae, established by Roewer in 1927 and named in honor of arachnologist S. C. Bishop. The genus contains two described species: B. jonesi, endemic to Alabama, and B. laciniosa, distributed more broadly across the southeastern United States. Both species belong to the diverse Laniatores suborder, characterized by relatively short legs and raptorial pedipalps adapted for predation.
Bohartia bromleyi
Nevada Longhorn Robber
Bohartia bromleyi is a species of robber fly in the family Asilidae, described by Hull in 1958. It belongs to the genus Bohartia, a small group of longhorn robber flies characterized by elongated antennae. The species is endemic to the western United States. Like other Asilidae, it is presumed to be an aerial predator of other insects.
Boloria alberta
Alberta fritillary
Boloria alberta is a small alpine fritillary butterfly endemic to the North American Rocky Mountains. Adults fly from July to early August in high-elevation habitats. The species exhibits sexual dimorphism in coloration, with males appearing dull orange and females pale orange to gray-brown. Larvae are specialized feeders on mountain avens (Dryas octopetala).
Boloria chariclea montinus
White Mountain Fritillary
The White Mountain Fritillary is a critically imperiled subspecies endemic to the alpine zone of the Presidential Range in New Hampshire's White Mountains. A glacial relict isolated for approximately 9,000 years, it represents one of the rarest butterfly populations in eastern North America. Systematic point-count surveys in 2012-2013 found highest densities in herbaceous-snowbank plant communities, though the more widespread heath-shrub-rush community likely supports the majority of adults. The subspecies is easily alarmed by human approach and exhibits variable detectability depending on weather conditions.
Bombus cockerelli
Cockerell's Bumble Bee, Cockerell's Bumblebee
Bombus cockerelli is a bumble bee species with the smallest known range of any bumble bee species worldwide, restricted to high-elevation localities in the White Mountains of New Mexico. First described in 1913 from six specimens, it remained unobserved between 1956 and 2011. Fewer than 30 specimens have ever been collected. The species was once considered a potential subspecies, but fresh specimens now allow for genetic analysis to resolve its taxonomic status. Its entire range falls within protected U.S. National Forest and tribal lands.
Booneacris
Wingless Mountain Grasshoppers
Booneacris is a genus of spur-throated grasshoppers in the family Acrididae, established by Rehn & Randell in 1962. The genus contains four described species, all characterized by reduced or absent wings. These grasshoppers are restricted to mountainous regions of western North America, with species found at high elevations. The common name "Wingless Mountain Grasshoppers" reflects their most distinctive trait and habitat preference.
Booneacris alticola
Marys Peak Wingless Grasshopper
Booneacris alticola, commonly known as the Marys Peak Wingless Grasshopper, is a species of spur-throated grasshopper described in 1962. The specific epithet 'alticola' refers to its high-elevation habitat. It belongs to the subfamily Melanoplinae, a diverse group of North American grasshoppers. The species is characterized by its wingless condition, an adaptation common in montane grasshopper species.
Booneacris glacialis
Wingless Mountain Grasshopper
Booneacris glacialis, commonly known as the wingless mountain grasshopper, is a species of spur-throated grasshopper in the family Acrididae. It is endemic to mountainous regions of eastern North America. The species is notable for being flightless, an adaptation to its high-elevation habitat. Three subspecies are currently recognized, varying in geographic distribution across the northern Appalachians and adjacent ranges.
Booneacris polita
Willamette wingless grasshopper
Booneacris polita, commonly known as the Willamette wingless grasshopper, is a flightless species of spur-throated grasshopper in the family Acrididae. It is endemic to the Pacific Northwest region of North America, with records primarily from Oregon. As its common name indicates, this species lacks functional wings, a trait that distinguishes it from most other grasshoppers and reflects its adaptation to stable, localized habitats.
Boreocanthon
Boreocanthon is a genus of ball-rolling dung beetles in the family Scarabaeidae, comprising thirteen recognized species. The genus is endemic to North America, with a distribution spanning from southern Canada to central Mexico. Species exhibit strong ecological associations with specific vegetation biomes, including eastern coniferous forests, prairies, arid shrublands, and desert habitats.
Boreus insulanus
Island Snow Scorpionfly
Boreus insulanus is a species of snow scorpionfly endemic to Vancouver Island, British Columbia. It belongs to the family Boreidae, a group of small, cold-adapted insects active during winter months. Like other snow scorpionflies, it lacks functional wings and is among the rarest insects encountered in its region. The species was described by Blades in 2002.
Brachinus patruelis
Brachinus patruelis is a small ground beetle in the bombardier beetle subfamily Brachininae. The species is endemic to the northeastern United States, with records from Massachusetts. Adults measure 5.7–8.3 mm in body length. Like other members of the genus, it possesses the defensive chemical secretion capability characteristic of bombardier beetles, though specific details of this behavior in B. patruelis have not been separately documented.
Brachypanorpa carolinensis
short-nosed scorpionfly
Brachypanorpa carolinensis, commonly known as the short-nosed scorpionfly, is a species of scorpionfly in the family Panorpodidae. The species is endemic to eastern North America. It is one of several species in the genus Brachypanorpa, which are characterized by their reduced wing venation and short rostrum compared to other scorpionflies.
Brachypnoea texana
Brachypnoea texana is a species of leaf beetle in the family Chrysomelidae. It is endemic to the Edwards Plateau in Texas, with a restricted geographic range. The species was first described by American entomologist Charles Frederic August Schaeffer in 1919. Limited information is available regarding its biology and ecology.
Bromleyus flavidorsus
Bromleyus flavidorsus is a species of robber fly in the family Asilidae, described by Hardy in 1945. The genus Bromleyus is endemic to Australia and contains relatively few described species. As with other Asilidae, this species is presumed to be a predatory fly, though specific ecological details remain undocumented in published literature. The species epithet 'flavidorsus' refers to a yellowish dorsal coloration.
Broscus
Broscus is a genus of ground beetles in the family Carabidae, tribe Broscini. The genus is native to the Palearctic, Nearctic, Near East, and North Africa. It contains approximately 25 described species, including several island endemics such as Broscus crassimargo on La Gomera (Canary Islands).
Bruneria yukonensis
Yukon slant-faced grasshopper, Yukon Grasshopper
Bruneria yukonensis is a species of slant-faced grasshopper in the family Acrididae. It is endemic to Yukon, Canada. As a member of the genus Bruneria, it belongs to a group of grasshoppers characterized by their slanted facial profile. The species was described by Vickery in 1969. Very little specific biological information has been published for this species.
Bryolymnia anthracitaria
Bryolymnia anthracitaria is a small noctuid moth described in 2007 from southeastern Arizona. It is one of the more recently described species in the genus Bryolymnia, a group of moths historically associated with moss and lichen habitats. The species remains poorly known, with fewer than ten verified observations documented.
Bryolymnia biformata
Bryolymnia biformata is a small noctuid moth described in 2010 from the sky island mountain ranges of southeastern Arizona. The species is distinguished by two distinct color forms of adults, which inspired its Latin name. It has been documented only from the Huachuca, Patagonia, and Santa Rita Mountains.
Bryolymnia viridata
Bryolymnia viridata is a small noctuid moth endemic to western California, ranging from Sonoma County to San Diego County. First described by Leon F. Harvey in 1876, it has a wingspan of approximately 27 mm. Adults are active from late May through mid-October. The species is placed in the tribe Elaphriini within the subfamily Noctuinae.
Bryophaenocladius chrissichuckorum
Spooner's Flightless Midge
Bryophaenocladius chrissichuckorum, commonly called Spooner's Flightless Midge, is a chironomid midge endemic to Georgia, United States. Described in 2012 from specimens collected in the late 1990s, this species has only been documented from specific granite outcrop habitats in the Georgia Piedmont region. Its flightless condition represents an unusual adaptation among chironomids.
Bucrates weissmani
Weissman's Conehead
Bucrates weissmani is a katydid species in the conehead tribe Copiphorini, described by Walker in 2014. It occurs in restricted montane habitats in the southwestern United States and adjacent Mexico. The species is known from limited collection records and iNaturalist observations.
Bycombia verdugoensis
Bycombia verdugoensis is a moth in the family Drepanidae, and the sole member of its genus. It was described by Hill in 1927 based on specimens from California. The species is known from extremely few records, with only two observations documented on iNaturalist. Its biology and ecology remain largely unknown due to this scarcity of data.
Cacotherapia angulalis
Cacotherapia angulalis is a species of snout moth in the family Pyralidae, first described by William Barnes and James Halliday McDunnough in 1918. It is endemic to California and belongs to a genus of relatively obscure pyralid moths. The specific epithet "angulalis" likely refers to angular features in wing pattern or body shape.
Calathus ruficollis ignicollis
Calathus ruficollis ignicollis is a flightless ground beetle subspecies endemic to the Transverse Ranges of southern California. First described by Casey in 1920, it represents the southern Sierra Nevada population of the broader C. ruficollis complex. Phylogeographic studies indicate this subspecies is genetically distinct from populations south and west, corresponding to a deep mitochondrial split within the species. Despite being flightless, the species shows limited geographic structure, suggesting recent range expansion or gene flow across mountain barriers.
Calathus ruficollis ruficollis
A flightless ground beetle subspecies distributed across southern California from Santa Barbara County to northern Baja California, including several Channel Islands. The subspecies is distinguished from the southern Sierra Nevada population (C. r. ignicollis) by genetic and geographic separation. Despite being flightless, populations show limited phylogeographic structure across the species' range, suggesting recent population expansion and gene flow across potential geographic barriers.
Californiulus chamberlini
Californiulus chamberlini is a species of millipede in the family Paeromopodidae, native to western North America. It is one of several species within the genus Californiulus, which is endemic to California and adjacent regions. Like other members of its family, it possesses the elongated, cylindrical body form typical of juliform millipedes. The species was described by Brölemann in 1922.
Californiulus euphanus
Californiulus euphanus is a millipede species in the family Paeromopodidae, described by Chamberlin in 1938. It is endemic to the Pacific Northwest of the United States, specifically found in northwestern Oregon and southwestern Washington. As a member of the order Julida, it belongs to a group of cylindrical, burrowing millipedes.
Callirhytis congregata
sausage flower gall wasp
Callirhytis congregata is a cynipid gall wasp native to California that induces distinctive galls on the catkins of three oak species: coast live oak (Quercus agrifolia), interior live oak (Quercus wislizeni), and canyon live oak (Quercus chrysolepis). The species was originally described by William Harris Ashmead in 1896 under the genus Andricus. It is considered locally common within its range. The galls are described as rugose, yellowish-brown woody swellings with multiple cells, appearing to grow from the tips of slender twigs with a long peduncle-like base.
Callophrys dumetorum dumetorum
A subspecies of hairstreak butterfly in the family Lycaenidae, endemic to coastal California. It is one of at least two recognized subspecies within Callophrys dumetorum, with the nominate subspecies restricted to a narrower range than the species as a whole. The species is known by the common names bramble hairstreak or lotus hairstreak.
Callophrys fotis
Desert Elfin, Early Elfin, Fotis Hairstreak, Strecker's Elfin, Arizona Gray Elfin
Callophrys fotis is a small gossamer-winged butterfly native to the southwestern United States. It has a wingspan of 19–28 millimeters. The species occurs in arid and semi-arid regions across six states, from southeastern California to northwestern New Mexico. Two subspecies are recognized: the nominate C. f. fotis and C. f. mojavensis described by Austin in 1998.
Callophrys mcfarlandi
Sandia Hairstreak
Callophrys mcfarlandi, the Sandia Hairstreak, is a small butterfly species native to North America with a restricted geographic range. It was discovered in 1958 in La Cueva Canyon, Albuquerque, New Mexico, by University of Kansas student Noel McFarland and formally described in 1960. The species was designated as one of New Mexico's state insects in 2003. It belongs to the hairstreak group within the family Lycaenidae.
Callophrys mossii bayensis
San Bruno Elfin
The San Bruno Elfin is a federally endangered butterfly subspecies endemic to the San Francisco Peninsula in California. It inhabits rocky outcrops and cliffs in coastal scrub habitat, with its distribution directly tied to that of its host plant, broadleaf stonecrop (Sedum spathulifolium). The subspecies was described by R. Brown in 1969 and is currently listed under the U.S. Endangered Species Act.
Calopteryx angustipennis
Appalachian jewelwing
Calopteryx angustipennis, the Appalachian jewelwing, is a large damselfly endemic to the eastern United States. It inhabits rocky rivers and streams with cold, fast-flowing water, particularly in woodland settings. Adults are active from spring through summer, with emergence timing varying by latitude.