California
Guides
Oreodytes humboldtensis
Oreodytes humboldtensis is a species of predaceous diving beetle in the family Dytiscidae, described by Zimmerman in 1985. As a member of the genus Oreodytes, it belongs to a group of small diving beetles primarily associated with running water habitats. The species epithet suggests a connection to the Humboldt region, likely referring to Humboldt County or the broader Humboldt Bay area of coastal northern California. Like other Oreodytes species, it is presumed to be an aquatic predator in freshwater systems.
Orgamara reducta
Orgamara reducta is a species of planthopper in the family Dictyopharidae, first described by Ball in 1909. The species belongs to the subfamily Orgeriinae, a group commonly known as grass-feeding planthoppers. It is distributed across parts of the southwestern United States and northwestern Mexico. Records indicate occurrence in California, New Mexico, and Baja California.
Ornithodoros turicata
relapsing fever tick
Ornithodoros turicata is a soft tick (family Argasidae) found in the midwestern and southwestern United States. It is the primary vector of Borrelia turicatae, the spirochete agent of tick-borne relapsing fever in humans. The tick has been documented feeding on at least 27 vertebrate host species across mammals, birds, reptiles, and amphibians. It exhibits autogenous reproduction (egg production without a bloodmeal) and transovarial transmission of spirochetes, enabling pathogen maintenance across generations.
Oroperla barbara
Gilltail Springfly
Oroperla barbara is a stonefly species in the family Perlodidae, first described by Needham in 1933. It is commonly known as the Gilltail Springfly. The species is recorded from California and Nevada in western North America. As a member of the order Plecoptera, it belongs to an ancient group of aquatic insects with gilled immature stages and terrestrial adults.
Orthoptochus squamiger
Orthoptochus squamiger is a species of broad-nosed weevil in the family Curculionidae, subfamily Entiminae. First described by Casey in 1888, this species is known from a very limited number of observations and museum records. It belongs to the tribe Peritelini, a group of weevils primarily associated with woody plants. The species appears to be restricted to the southwestern United States and adjacent Mexico.
Panaphis juglandis
Walnut Aphid, Large Walnut Aphid
Panaphis juglandis, the large walnut aphid, is a phloem-feeding pest of walnut trees (Juglans regia). It colonizes exclusively the upper (adaxial) surface of walnut compound leaves, forming dense colonies along the main vascular veins of the outer leaflets. Native to the Old World (Central Asia and southeastern Europe), it has spread across Europe and was introduced to California in the early 20th century. The species reduces tree vigor, nut yield, and quality, and excretes honeydew that promotes sooty mold growth. It forms mutualistic relationships with ant species that tend and protect colonies from predators.
Panscopus bufo
broad-nosed weevil
Panscopus bufo is a species of broad-nosed weevil in the beetle family Curculionidae, first described by Buchanan in 1927. It is native to North America, with confirmed records from California counties including El Dorado, Inyo, Madera, and Mariposa. Like other members of the genus Panscopus, it belongs to the diverse group of weevils characterized by their elongated snouts and herbivorous habits, though specific ecological details for this species remain poorly documented.
Parancistrocerus declivatus
potter wasp
Parancistrocerus declivatus is a potter wasp in the family Vespidae, native to the southern coastal regions of California and Baja California. Originally described in the genus Stenodynerus, it was later transferred to Parancistrocerus. The type locality is La Laguna in the Sierra Laguna mountains of Baja California. Like other members of the subfamily Eumeninae, it is a solitary wasp that constructs nests from mud or other materials.
Paraneotermes simplicicornis
Desert Dampwood Termite
Paraneotermes simplicicornis is a desert-dwelling dampwood termite native to arid regions of southwestern North America. It is notable for its distinctive cooperative tunneling behavior, in which workers pass excavated soil backward through the tunnel in a bucket-brigade fashion rather than carrying it individually. The species colonizes dead and decaying Joshua trees (Yucca brevifolia) and initiates new colonies following monsoon rains, typically in September.
Paraproba pendula
Paraproba pendula is a species of plant bug in the family Miridae, first described by Van Duzee in 1914. It belongs to the diverse mirid fauna of North America, a family known for its ecological importance as predators and herbivores in various plant communities. The species is documented from California, USA.
Paravilla splendida
Paravilla splendida is a species of bee fly (family Bombyliidae) described by Hall in 1981. It belongs to the subfamily Anthracinae and tribe Villini. The species has a restricted geographic range limited to California and Baja California Norte, Mexico.
Paruroctonus silvestrii
California common scorpion, stripe-tailed scorpion
Paruroctonus silvestrii is a small scorpion in the family Vaejovidae, native to the coastal regions of California and Baja California. It is commonly known as the California common scorpion or stripe-tailed scorpion. The species inhabits dry areas where it constructs and occupies burrows. It is distinguished by four longitudinal brown lines on the ventral surface of its tail, which gives rise to its 'stripe-tailed' common name.
Pealius kelloggi
Hollyleaf Cherry Whitefly
Pealius kelloggi is a species of whitefly in the family Aleyrodidae. It has been recorded from California and is associated with hollyleaf cherry (Prunus ilicifolia). The species was described by Bemis in 1904 and is one of approximately 44 observations documented on iNaturalist. Like other whiteflies, it is a sap-feeding insect that develops through distinct immature stages before reaching the winged adult form.
Pedomoecus sierra
Pedomoecus sierra is a species of caddisfly in the family Apataniidae, described by Ross in 1947. It is known from the Sierra Nevada region of California. Like other members of the order Trichoptera, the larvae are aquatic and construct protective cases from silk and environmental materials. The specific epithet 'sierra' refers to its type locality in the Sierra Nevada mountains.
Pelochrista nr-bolanderana
Pelochrista nr-bolanderana is a tortricid moth in the family Tortricidae, subfamily Olethreutinae. The 'nr' designation indicates this is a near-relative of P. bolanderana, not a confirmed species identification. It has been documented in blacklight surveys in California. Like other Pelochrista species, it is a small moth with typical tortricid wing posture at rest.
Pentidotea aculeata
Pencil Isopod
Pentidotea aculeata is a marine isopod in the family Idoteidae, commonly known as the Pencil Isopod. It inhabits the intertidal zone along the coast of California. The species was described by Stafford in 1913. Like other idoteid isopods, it is adapted to life in shallow coastal waters where it likely feeds on algae and detritus.
Perdita californica
California Fairy Bee
Perdita californica is a small mining bee in the family Andrenidae, commonly known as the California Fairy Bee. The species is native to California and Baja California, with two recognized subspecies: P. c. californica and P. c. inopina. Like other members of the genus Perdita, it is a solitary bee. The genus Perdita contains over 700 species, many of which are specialist pollinators with narrow host plant associations.
Petalium californicum
Petalium californicum is a species of beetle in the family Anobiidae (formerly placed in Ptinidae). It is a small wood-boring beetle native to western North America. The species was described by Henry Clinton Fall in 1905 based on specimens from California.
Phalangodidae
Phalangodid Harvestmen
Phalangodidae is a family of small harvestmen in the suborder Laniatores, containing approximately 30 genera and more than 100 described species. Members are characterized by pedipalps armed with prominent spines and body lengths generally under 3 mm. The family is primarily distributed in the Holarctic region, with exceptional diversity in the western Nearctic, particularly California. Several species, especially in the genus Texella, are obligate cave-dwellers exhibiting troglomorphic traits such as depigmentation and reduced eyes.
Phaneroptera nana
Mediterranean katydid, southern sickle bush-cricket
Phaneroptera nana is a small katydid native to mainland Europe, the Near East, and North Africa. It has established invasive populations in California (first recorded 1952), Oregon (since 2015), and South America, likely spreading via shipping. The species inhabits sunny, dry environments with shrubs and low tree branches. Adults are active primarily in summer and fall.
Pheidole clementensis
San Clemente Island Big-headed Ant
Pheidole clementensis is a species of big-headed ant in the genus Pheidole, described by Gregg in 1969. It is endemic to San Clemente Island, California, and is recognized as a distinct species within the highly diverse genus Pheidole, which contains over 1,000 species globally. Like other Pheidole species, it exhibits worker polymorphism with distinct soldier and minor worker castes.
Philoxenus desertorum
Philoxenus desertorum is a species of clown beetle in the family Histeridae. It was described by Mazur in 1991 and is currently the sole described species in the genus Philoxenus. The species has been recorded from desert regions in California, USA, and Sonora, Mexico. Taxonomic authorities treat this name as a synonym of Hypocaccus desertorum.
Phobetus saylori
Phobetus saylori is a species of scarab beetle in the family Scarabaeidae, described by Cazier in 1937. It belongs to the tribe Phobetusini within the subfamily Melolonthinae. The species is known from a small number of observations and has a restricted distribution in western North America.
Phryganeopsis
Phryganeopsis is a monotypic genus of moths in the family Tineidae, containing a single species, Phryganeopsis brunnea. The genus is endemic to California. Little detailed information is available about its biology or ecology.
Phryganeopsis brunnea
Phryganeopsis brunnea is a species of moth in the family Tineidae, the sole member of its monotypic genus. It is endemic to California. The species was described by Walsingham in 1881. Very little is known about its biology or ecology beyond its taxonomic placement and geographic occurrence.
Phryganidia
California Oak Moth
Phryganidia is a genus of prominent moths in the family Notodontidae, containing three species found in western North America. The genus is best known for Phryganidia californica, commonly called the California Oak Moth or California Oakworm, which undergoes periodic population outbreaks that can cause extensive defoliation of oak trees along the California coast. The genus was formerly placed in its own family, Dioptidae, but has been reclassified into Notodontidae. Adults are dull brown with weak flight, while larvae are specialized feeders on oak foliage.
Phyllolabis flavida
Phyllolabis flavida is a species of crane fly in the family Limoniidae, described by Charles Paul Alexander in 1918. It is a member of the genus Phyllolabis, which belongs to the subfamily Limnophilinae. The species is known from California, USA, and is part of the Nearctic fauna. Very little specific biological information has been published for this species.
Phyllonorycter manzanita
Phyllonorycter manzanita is a leaf-mining moth in the family Gracillariidae. The species is endemic to California and was described by Braun in 1925. Larvae create characteristic mines in the leaves of manzanita species (Arctostaphylos), with documented hosts including Arctostaphylos glauca and Arctostaphylos manzanita.
Phyllonorycter memorabilis
Phyllonorycter memorabilis is a small moth in the family Gracillariidae, described by Braun in 1939. It is endemic to California, United States. The larvae are leaf miners that feed on species of Lathyrus, creating distinctive mines within the leaf tissue.
Phymatodes nitidus
sequoia cone borer
Phymatodes nitidus is a longhorn beetle (family Cerambycidae) native to western North America. The species is notable for its specialized reproductive association with conifers, specifically laying eggs on giant sequoia and coast redwood cones. Larvae burrow into these cones to develop. The species was described by LeConte in 1874. Phymatodes mojavensis was synonymized under P. nitidus in 2010.
Phymonotus
Phymonotus is a monotypic genus of shield-backed katydid erected in 2011, containing the single species P. jacintotopos. The genus is distinguished by an unusually enlarged dome-like pronotum, a distinctive calling song, and seven additional morphological features. It is considered a Pleistocene relic taxon endemic to high-elevation conifer forests of the San Jacinto Mountains in southern California.
Phytocoris eurekae
Phytocoris eurekae is a species of plant bug in the family Miridae, described by Bliven in 1966. It belongs to a large genus of mirid bugs that are primarily associated with vegetation. The species is documented from western North America, with records from California. Like other members of its genus, it possesses piercing-sucking mouthparts characteristic of true bugs.
Phytocoris maritimus
Phytocoris maritimus is a species of plant bug in the family Miridae, described by Van Duzee in 1920. The specific epithet 'maritimus' suggests an association with coastal or marine-influenced habitats. Like other members of the genus Phytocoris, it is likely a plant-feeding insect, though detailed biological information remains limited.
Phytocoris rufoscriptus
Phytocoris rufoscriptus is a species of plant bug in the family Miridae, described by Van Duzee in 1914. It belongs to a large genus of predatory and plant-feeding true bugs. The species has been recorded from California, USA. Like other members of Phytocoris, it likely exhibits a combination of phytophagy and opportunistic predation on small insects.
Pissonotus melanurus
Pissonotus melanurus is a species of delphacid planthopper first described by Van Duzee in 1917. It belongs to the family Delphacidae, a group characterized by a large, movable spur on the hind tibia. The species is known from limited records in western North America.
Platycentrus acuticornis
Platycentrus acuticornis is a treehopper species in the tribe Platycentrini, subfamily Centrotinae. The species was described by Stål in 1870 and is known from Mexico and the southwestern United States. Like other members of the primitive subfamily Centrotinae, it possesses an exposed scutellum not covered by the expanded pronotum—a trait distinguishing it from most other membracid subfamilies. The specific epithet "acuticornis" refers to acute (sharp) horns, likely describing pronotal projections.
Platyceroides californicus
Platyceroides californicus is a species of stag beetle in the family Lucanidae, endemic to California. It is a small to medium-sized beetle with reduced mandibles compared to many lucanids. The genus Platyceroides is distinguished from the similar Platycerus by antennal club structure and male genitalia morphology. Very few observations exist for this species, and its biology remains poorly documented.
Platyceroides infernus
Platyceroides infernus is a species of stag beetle in the family Lucanidae, described from California in 2017. It belongs to a genus of small to medium-sized stag beetles characterized by reduced mandibles in males compared to other lucanid genera. The species epithet "infernus" (Latin for "hell") references its type locality in Death Valley, California. Like other Lucanidae, adults are nocturnal and larvae develop in decaying wood.
Platyceroides latus
Platyceroides latus is a stag beetle species described by Fall in 1901. It belongs to the family Lucanidae, a group characterized by enlarged mandibles in males. The species is known from a limited number of observations, with records concentrated in California and Nevada. Its biology remains poorly documented.
Platylabops pecki
Platylabops pecki is a species of ichneumonid wasp described by Heinrich in 1961. The genus Platylabops belongs to the family Ichneumonidae, one of the largest families of parasitoid wasps. Very few records of this species exist in public databases. A single observation has been documented from White Fox, California.
Platylyra californica
California Chaparral Katydid
Platylyra californica is a katydid species endemic to California, commonly known as the California Chaparral Katydid. It belongs to the family Tettigoniidae and is associated with chaparral and coastal scrub habitats. The species was described by Scudder in 1898 and has been documented in over 1,100 iNaturalist observations, indicating it is relatively well-recorded within its restricted range.
Platynota islameconae
Platynota islameconae is a species of tortricid moth described by Powell & Brown in 2012. It is endemic to California, United States. As a member of the genus Platynota, it belongs to a group of leafroller moths whose larvae are known to feed within rolled or folded leaves of host plants.
Platypedia barbata
Platypedia barbata is a species of cicada described by Davis in 1920. Like other members of its genus, it lacks the timbal organs used by most cicadas for sound production. Instead, it produces sound through crepitation—snapping its wings against its body or substrate. The species occurs in California and is part of a diverse western North American genus comprising 21 species and four subspecies.
Platypedia scotti
Platypedia scotti is a species of cicada in the family Cicadidae, described by Davis in 1935. Like other members of the genus Platypedia, males of this species lack tymbal organs and produce sound through crepitation—snapping their wings against vegetation—rather than the typical cicada singing mechanism. The species is known from California and belongs to a group of western North American cicadas often called "wing-bangers" or "wing-tappers."
Platystoechotes
Platystoechotes is a genus of lacewings in the family Ithonidae, established by Carpenter in 1940. The genus belongs to the order Neuroptera, a group of insects characterized by their highly veined, membranous wings. Members of Ithonidae, including Platystoechotes, are often associated with warm, dry habitats and are among the more relictual lineages of Neuroptera.
Pleocoma puncticollis
Black Rain Beetle
Pleocoma puncticollis, commonly known as the black rain beetle, is a species of rain beetle in the family Pleocomidae. It is endemic to California. Adults are known to emerge and fly during rainy conditions, a trait characteristic of the genus.
Pleocoma staff
rain beetle
Pleocoma staff is a species of rain beetle in the family Pleocomidae, described by Schaufuss in 1870. Rain beetles are a small, relict group of scarabaeoid beetles endemic to western North America. This species has been recorded from California and Utah.
Pleromella opter
Pleromella opter is a moth species and the sole member of the monotypic genus Pleromella within the family Noctuidae. It is endemic to western North America, occurring in southern Oregon, California, and Baja California. The species was first described by Harrison Gray Dyar Jr. in 1921. It is one of approximately 124 observed records documented in natural history databases.
Poanes melane
umber skipper
Poanes melane, commonly known as the umber skipper, is a butterfly species in the family Hesperiidae. It has been recorded in butterfly monitoring studies in Central California, where it occurs in dry vegetation habitats. The species is associated with specific host plants including Euthamia (goldentops) and Epilobium (willowherbs/fireweeds).
Podabrus appendiculatus
Podabrus appendiculatus is a soldier beetle in the family Cantharidae, described by Fall in 1928. It belongs to a genus commonly found in California and across North America. Like other soldier beetles, it is likely predatory on soft-bodied insects, though species-specific documentation is limited.