Western-north-america
Guides
Xyela middlekauffi
Xyela middlekauffi is a species of sawfly in the family Xyelidae, one of the most primitive lineages within Hymenoptera. Species in this genus are associated with conifer hosts, particularly pines. Xyela middlekauffi has been documented from a limited number of observations, suggesting either restricted distribution or low detectability. Like other xyelids, adults likely have short life spans and are active during early spring.
Xylocopa californica californica
Northern California Carpenter Bee
Xylocopa californica californica is a subspecies of carpenter bee native to western North America. It is one of three recognized carpenter bee species in California and is distinguished by its bluish metallic body reflections. The subspecies is found in mountain foothill regions of northern and southern California. Like other carpenter bees, it nests by tunneling into wood and serves as an important pollinator in native plant communities.
Xylocopa tabaniformis androleuca
Pale-male Horse-fly Carpenter
Xylocopa tabaniformis androleuca is a subspecies of the mountain carpenter bee, distinguished by its pale male coloration. As part of the Xylocopa tabaniformis species complex, it shares the incipiently social behavior and distinctive gut microbiome characteristic of this group. Research has shown that carpenter bees in this complex harbor bacterial communities more similar to eusocial bees like honey bees and bumble bees than to solitary bees, challenging assumptions about sociality as the main driver of microbiome structure. The subspecies occurs in western North America, where females nest in wood and males exhibit the pale facial markings that give this taxon its common name.
Xylocoris californicus
Xylocoris californicus is a small predatory bug in the family Anthocoridae (minute pirate bugs). The species is native to western North America and is found in California and surrounding regions. Like other members of its genus, it is likely a generalist predator of small arthropods, though specific ecological studies on this species are limited.
Yingabruxia sordida
Yingabruxia sordida is a species of skeletonizing leaf beetle in the family Chrysomelidae. It is known from western North America and Baja California, with records extending from British Columbia south to Texas. The species belongs to a genus of leaf-feeding beetles whose members skeletonize foliage by consuming leaf tissue between the veins.
Yosemitia graciella
Yosemitia graciella is a species of snout moth in the family Pyralidae, first described by George Duryea Hulst in 1887. It is one of approximately 20 described species in the genus Yosemitia, a group of small moths primarily distributed in western North America. The species occurs across arid and semi-arid regions of the southwestern United States.
Zagloba ornata
Zagloba lady beetle
Zagloba ornata is a small lady beetle (family Coccinellidae) native to western North America. Adults measure 1.75–2 mm in length, making them among the smaller lady beetles. The species exhibits variable coloration, with a dark brown to light brown body and distinctive yellow markings on the pronotum and elytra. It has been recorded from southern Arizona and California north to southwestern Oregon.
Zapada
forestflies, spring stoneflies, little brown stoneflies
Zapada is a genus of small spring stoneflies in the family Nemouridae, commonly known as forestflies or little brown stoneflies. The genus contains at least 10 described species distributed across western North America, from Alaska and the Rocky Mountains to California. Adults are 5–8 mm in body length and emerge in early spring, often February through April depending on elevation and species. Nymphs are aquatic shredders that process leaf litter and other organic matter in cold, well-oxygenated streams.
Zapada cordillera
Cordilleran Forestfly
Zapada cordillera is a species of spring stonefly in the family Nemouridae, commonly known as the Cordilleran Forestfly. Described in 1971 from specimens in the western United States, this small aquatic insect is part of a genus whose nymphs are characterized by distinctive branched cervical gills retained into adulthood. As a member of the Nemouridae, it contributes to stream ecosystem function as a leaf-shredding detritivore and serves as an indicator of water quality in its montane habitat.
Zapada frigida
Frigid Forestfly
Zapada frigida is a species of spring stonefly in the family Nemouridae, commonly known as the Frigid Forestfly. Like other members of the genus Zapada, adults retain diagnostic branched cervical gills from the nymphal stage, with two sets of branched gills on each side of the body. The species has been documented from western North America including Alberta, Alaska, British Columbia, California, and Colorado.
Zarhipis
glowworm beetles
Zarhipis is a genus of glowworm beetles in the family Phengodidae, containing three recognized species restricted to western North America. Members of this genus exhibit sexual dimorphism, with females being larviform and bioluminescent while males are winged and non-luminous. The genus has been subject to population genetic studies, particularly for Zarhipis integripennis, revealing significant geographic structure and sex-biased dispersal patterns.
Zilus aterrimus
Western Velvethead Lady Beetle
Zilus aterrimus is a minute lady beetle species in the family Coccinellidae. It is known from western North America, with records from Idaho and Washington south to California and Arizona. Adults measure approximately 1.25–1.60 mm in length.
Zoniagrion exclamationis
Exclamation Damsel
Zoniagrion exclamationis, commonly known as the Exclamation Damsel, is a species of damselfly in the family Coenagrionidae. It is the sole species in its genus and is endemic to western North America. The species was first described by Selys in 1876 and is recognized by its distinctive coloration and patterning. It is a relatively well-documented damselfly with over 300 observations recorded on citizen science platforms.
Zotheca
elder moth
Zotheca is a monotypic genus of moths in the family Noctuidae, containing a single species, Zotheca tranquilla (the elder moth). The genus is restricted to western North America, where adults are active during summer months. The common name derives from the larval host plant, elderberry (Sambucus).
Zygiella carpenteri
Zygiella carpenteri is an orb-weaving spider native to western North America. It was formerly classified in the genus Zygiella but has been reclassified to Parazygiella carpenteri in some taxonomic treatments. The species constructs complete orb webs rather than the incomplete webs with missing sectors typical of some related species. It occurs in disjunct populations in the Sierra Nevada mountains, the California coast, and southeastern Washington.