Western-hemisphere
Guides
Agapostemon
Striped Sweat Bees, Metallic Green Sweat Bees
Agapostemon is a genus of sweat bees (Halictidae) comprising approximately 42 species distributed across the Western Hemisphere from Canada to Argentina. Most species exhibit metallic green or blue coloration, particularly on the head and thorax. Unlike many other sweat bees in the family, Agapostemon species are not attracted to human sweat. The genus includes both solitary and communal species, with all species nesting in the ground. Some species, such as A. virescens, form communal aggregations where multiple females share a common nest entrance while maintaining separate brood cells.
Argia
Dancers
Argia is the largest and most diverse genus in the damselfly subfamily Argiinae, comprising approximately 114 described species with additional species awaiting description. Members are commonly known as "dancers" due to their characteristic jerky, erratic flight pattern. The genus is restricted to the Western Hemisphere, with species ranging from North America through Central and South America and the Caribbean. Despite the genus name deriving from Greek for "laziness," these damselflies are notably active and alert predators. The genus has been subject to extensive taxonomic revision, with multiple revisions published between 1994 and 2022.
Argia barretti
Comanche Dancer
Argia barretti, the Comanche Dancer, is a species of narrow-winged damselfly in the family Coenagrionidae. It occurs in Central America and North America. The IUCN lists it as Least Concern with a stable population. As a member of the genus Argia, it belongs to the largest genus in the subfamily Argiinae, comprising approximately 114 species in the Western Hemisphere.
Argia nahuana
Aztec Dancer
Argia nahuana, commonly known as the Aztec Dancer, is a damselfly species in the family Coenagrionidae. It is a member of the diverse genus Argia, which contains approximately 114 species in the Western Hemisphere. The species exhibits distinctive morphological features including a forked dark stripe on the side of the thorax and blue postocular spots.
Ascra florida
Ascra florida is a species of stink bug in the family Pentatomidae, tribe Carpocorini. The genus Ascra contains approximately 20 described species distributed primarily in the Western Hemisphere. Records for A. florida are sparse, with limited documented observations.
Balclutha flavescens
Balclutha flavescens is a leafhopper species in the family Cicadellidae, originally described as Eugnathodus flavescens by Baker in 1903. It has been documented in Florida, United States, where specimens were collected for COI barcode analysis as part of broader studies on the Balclutha fauna. The species was included in phylogenetic analyses of mitochondrial DNA to clarify relationships among Western Hemisphere Balclutha species. Type specimens have been illustrated to resolve taxonomic confusion with similar species.
Buenoa
backswimmer
Buenoa is a genus of backswimmers (family Notonectidae) established by George Willis Kirkaldy in 1904 to accommodate Western Hemisphere species formerly placed in Anisops. The genus is distinguished from Anisops by males having a two-segmented front tarsus, versus one-segmented in the latter genus. Buenoa contains 69 described species distributed across the Americas. Members are aquatic predators inhabiting diverse freshwater and saltwater environments.
Calliopsis
mining bees, panurgine bees
Calliopsis is a genus of solitary mining bees in the family Andrenidae, comprising over 80 described species distributed throughout the western hemisphere. These small to medium-sized bees are ground-nesting, with females excavating burrows in sandy or loose soils. The genus includes both polylectic and oligolectic species, with some showing tight specialization to particular pollen hosts such as Prosopis. Several species have been studied in detail for their nesting biology, foraging behavior, and host-parasite relationships with cleptoparasitic bees.
Clarkhydrus roffii
Clarkhydrus roffii is a species of predaceous diving beetle in the family Dytiscidae, subfamily Hydroporinae. It belongs to a genus of small diving beetles distributed in the Western Hemisphere. The species was described by Clark in 1862 and is known from limited collection records in North and Middle America. Like other members of Dytiscidae, it is an aquatic predator, though specific ecological details remain poorly documented.
Decua
Decua is a genus of leafhoppers in the family Cicadellidae, tribe Cicadellini, established by Oman in 1949. As a member of the subfamily Cicadellinae, it belongs to a diverse group of sap-feeding insects commonly known as sharpshooters. The genus is part of the large leafhopper fauna of the Western Hemisphere. No species-level biological data or diagnostic descriptions are readily available in major databases.
Eulepidotis rectimargo
Eulepidotis rectimargo is a moth species in the family Erebidae, described by Achille Guenée in 1852. The species occurs in tropical regions of the Western Hemisphere, with records from Mexico, Central America, and South America. It has been documented as far north as Texas, representing a northward range extension recorded in 2004. The species belongs to the genus Eulepidotis, a group of moths within the subfamily Calpinae.
Exomalopsis
Exomalopsis is a genus of solitary bees in the family Apidae, tribe Exomalopsini, comprising nearly 90 described species with many more undescribed. These bees are restricted to the Western Hemisphere, occurring in both Neotropical and Nearctic realms. Species nest communally in soil, excavating deep tunnels with branching underground pathways leading to individual brood cells. The genus is notable for its complex associations with kleptoparasitic cuckoo bees and parasitoid wasps.
Haematosiphoninae
Haematosiphoninae is a subfamily of Cimicidae (bed bugs) established in 1912. The group comprises ectoparasitic insects that inhabit bird nests, with documented associations to Psittacidae (parrots) and other avian hosts. Five genera are recognized: Cimexopsis, Ornithocoris, Haematosiphon, Hesperocimex, and Psitticimex, plus the recently described Cyanolicimex. Members are restricted to the Western Hemisphere, with the southernmost records from Río Negro province, Argentina.
Helobata larvalis
Pickerelweed Water Beetle
Helobata larvalis is a water scavenger beetle in the family Hydrophilidae, commonly known as the Pickerelweed Water Beetle. It has a broad distribution across the Americas, occurring from the United States through Central America to South America, including Caribbean islands. The species has been recorded from diverse biomes including the Cerrado of Brazil. As a member of the Acidocerinae subfamily, it inhabits aquatic or semi-aquatic environments.
Maruina
Maruina is a genus of moth flies (Psychodidae) containing approximately 39 described species. The genus is unique among Psychodidae in being strictly aquatic, with larvae and pupae specially adapted for life in flowing water. It is restricted to the Western Hemisphere, with the majority of species occurring in the Neotropical region. The genus is divided into two subgenera: Aculcina and Maruina.
Metepeira
labyrinth spiders, labyrinth orb-weavers
Metepeira is a genus of small orb-weaving spiders in the family Araneidae, first described by F. O. Pickard-Cambridge in 1903. The genus contains 44 species distributed from Argentina to Canada, with highest diversity in western North America and Mexico. These spiders construct distinctive webs combining a small orb web with a tangled, labyrinthine snare surrounding a thimble-like retreat. Some species exhibit facultative colonial behavior, with individuals interlacing webs over large areas under conditions of high prey availability.
Pellaea stictica
Pellaea stictica is a species of stink bug (family Pentatomidae) distributed across temperate regions of the Western Hemisphere, including North America, South America, and the Caribbean. First described by Dallas in 1851, it has been documented as an edible insect in Mexico, where both adults and nymphs are consumed. Its range in the United States expanded notably in 2021 when it was first recorded in California, having previously been known only from Texas north of Mexico.
Pseudomorpha
Western False-form Beetles
Pseudomorpha is a genus of ground beetles in the family Carabidae, subfamily Pseudomorphinae. The genus contains 35 described species distributed across North, Central, and South America. Members are commonly known as Western False-form Beetles. The genus was established by William Kirby in 1823.
Rasahus hamatus
corsair
Rasahus hamatus is a species of corsair, a group of predatory assassin bugs in the family Reduviidae. It occurs widely across the Western Hemisphere, from North America through Central America and the Caribbean to South America, including the Galápagos Islands. As a member of the subfamily Peiratinae, it belongs to a lineage known for ground-dwelling habits and active predation on other arthropods.
Sphex ichneumoneus
Great Golden Digger Wasp, Great Golden Sand Digger
Sphex ichneumoneus is a large, conspicuous solitary wasp distributed across the Western Hemisphere from Canada to South America. Females excavate vertical burrows in sandy soils, provisioning individual cells with paralyzed katydids and related Orthoptera as food for their larvae. The species exhibits a distinctive fixed action pattern during prey retrieval, repeatedly inspecting the burrow entrance before dragging prey inside by the antennae—a behavior famously cited in discussions of genetic determinism. Adults forage for nectar at flowers and are frequently observed on blooms of rabbitbrush, prairie clover, and grape.