Solitary-bee
Guides
Melissodes paroselae
Parosela Long-horned Bee
Melissodes paroselae is a species of long-horned bee in the family Apidae, first described by Cockerell in 1905. Like other members of the genus Melissodes, it is characterized by elongated antennae, particularly in males. The species is distributed across Central America and North America. As a member of the tribe Eucerini, it is a solitary, ground-nesting bee that contributes to pollination of native flora.
Melissodes rivalis
rival long-horned bee, Western Thistle Longhorn Bee
Melissodes rivalis is a solitary long-horned bee in the family Apidae, native to northern North America. Males are distinguished by antennae that may exceed their body length. Females construct individual underground nests and provision them with pollen, while males form sleeping aggregations on flower heads. The species has been documented pollinating thistles (Cirsium sp.).
Melissodes stearnsi
long-horned bee
Melissodes stearnsi is a species of long-horned bee in the family Apidae, described by Cockerell in 1905. Like other members of the genus Melissodes, it belongs to the tribe Eucerini, a group of solitary, ground-nesting bees. The species is found in North America. Available information about this species specifically is limited, with most detailed behavioral and ecological knowledge coming from better-studied congeners such as Melissodes agilis.
Melissodes subillatus
Melissodes subillatus is a species of long-horned bee in the family Apidae, described by LaBerge in 1961. It belongs to a genus of solitary, ground-nesting bees commonly known as long-horned bees due to the elongated antennae of males. Like other Melissodes species, it is native to North America and contributes to pollination of flowering plants. Specific ecological details for this species remain poorly documented in published literature.
Melissodes tepaneca
Tepanec Long-horned Bee
Melissodes tepaneca is a species of long-horned bee in the family Apidae. It is distributed across Central America and North America. The species belongs to a genus characterized by males with notably elongated antennae. Like other Melissodes species, it is a solitary ground-nesting bee that contributes to pollination of native flora.
Melissodes tepidus
Long-horned bee
Melissodes tepidus is a species of long-horned bee in the family Apidae, native to North and Central America. Like other members of the genus Melissodes, males exhibit distinctive sleeping aggregations on vegetation at night while females nest solitarily in the ground. The species contributes to pollination of various flowering plants. It is one of more than 1600 native bee species recorded in California alone.
Melissoptila otomita
Otomi Longhorn
Melissoptila otomita is a species of longhorn bee in the family Apidae, tribe Eucerini. Commonly known as the Otomi Longhorn, this bee belongs to a genus characterized by males with exceptionally long antennae. The species occurs across much of the Americas, from North America through Middle America to South America. As a member of the Eucerini, it is a solitary bee that likely nests in the ground and visits flowers for pollen and nectar.
Melitoma grisella
Great Plains Turret Bee
Melitoma grisella is a species of solitary bee in the family Apidae, commonly known as the Great Plains Turret Bee. It belongs to the tribe Emphorini, a group of bees known for constructing distinctive turret-like nest entrances. The species was described by Cockerell and Porter in 1899 and is native to North America.
Melitoma taurea
mallow bee, Morning Glory Turret Bee
Melitoma taurea, commonly known as the mallow bee or Morning Glory Turret Bee, is a solitary bee species in the family Apidae. It belongs to the chimney bee group, known for constructing distinctive turret-like nest entrances. The species is notable for possessing an exceptionally long proboscis that extends to the abdomen even when folded. It occurs across North America and has been documented in parts of Central and South America.
Melitta
Blunt-horn Bees
Melitta is a genus of solitary bees in the family Melittidae, comprising approximately 40 species distributed across Africa and the northern temperate zone. Most species are Palaearctic in distribution, with three rare species occurring in North America. These bees are commonly known as Blunt-horn Bees and are characterized by their specialized ecological associations with particular host plants.
Mexalictus arizonensis
Arizona mexalictus
Mexalictus arizonensis, commonly known as the Arizona mexalictus, is a species of sweat bee in the family Halictidae. It is a small, solitary bee endemic to the southwestern United States. The species was described by Eickwort in 1978 and is one of the few members of the genus Mexalictus, a group of bees restricted to North America. Like other halictids, it is likely a generalist pollinator, though specific ecological details remain poorly documented.
Micralictoides ruficaudus
Red-tailed Micro-Shortface
Micralictoides ruficaudus is a species of sweat bee in the family Halictidae, first described by Michener in 1937. It is a member of the subfamily Rophitinae, a group of solitary bees often associated with specialized pollen-collecting behaviors. The species is known from North America, with observations documented across multiple regions. As with many halictid bees, it likely plays a role in pollination of native flora.
Nomada besseyi
Bessey's Nomad Bee
Nomada besseyi is a species of cuckoo bee in the family Apidae, first described by Swenk in 1913. Like other members of the genus Nomada, it is a kleptoparasite that lays its eggs in the nests of host bee species, particularly mining bees in the genus Andrena. The species is native to North America and exhibits the characteristic wasp-like appearance typical of nomad bees, lacking the branched body hairs used for pollen collection by non-parasitic bees.
Nomada luteoloides
Black-and-yellow Nomad Bee
Nomada luteoloides is a species of cuckoo bee in the family Apidae, native to North America. As a kleptoparasite, it does not construct its own nest or collect pollen, instead laying eggs in the nests of host bee species. The female offspring develop by consuming the host's provisions and often the host egg or larva. The species is part of the diverse Nomada genus, which contains numerous cuckoo bee species that parasitize various ground-nesting bees, particularly in the genus Andrena.
Nomadini
Nomad bees
Nomadini is a tribe of cleptoparasitic bees within the subfamily Nomadinae, family Apidae. The tribe contains the genus Nomada, one of the largest genera of cuckoo bees with over 850 species worldwide. These bees are obligate cleptoparasites that lay eggs in the nests of other bees, primarily mining bees (Andrena). They lack pollen-carrying structures and exhibit wasp-like coloration with red, black, and yellow patterns.
Nomia maneei
Manee's Nomia
Nomia maneei is a ground-nesting bee in the family Halictidae, first described by Cockerell in 1910. It belongs to the genus Nomia, which includes several species of solitary bees that nest in soil. The species is known from North America, though specific details about its biology remain poorly documented compared to its congener Nomia melanderi, which is intensively managed for alfalfa pollination.
Nomia melanderi
alkali bee, Alkali Nomia
Nomia melanderi, commonly known as the alkali bee, is a solitary ground-nesting bee native to the western United States. It is the world's only intensively managed ground-nesting bee, commercially cultivated for alfalfa pollination. The species nests in dense aggregations in moist, alkaline soils and exhibits traits that preceded insect sociality, including defense of offspring against pathogens and predators.
Osmia
Mason Bees
Osmia is a large genus of solitary bees in the family Megachilidae, commonly known as mason bees. The genus includes approximately 500 species worldwide, with many species native to North America. Mason bees are named for their use of mud or other masonry materials to construct and seal nest cells. They are important pollinators of agricultural crops and native plants, and several species are managed commercially for orchard pollination. Unlike honey bees, mason bees are solitary, do not produce honey, and rarely sting.
Osmia aglaia
Oregon berry bee
Osmia aglaia is a solitary mason bee native to the western United States. It is commonly known as the Oregon berry bee due to its specialized role as a pollinator of brambles, particularly raspberries and blackberries. The species exhibits metallic coloration and nests in pre-existing wood tunnels. Adults are active in late spring, coinciding with Rubus bloom periods.
Osmia bucephala
bufflehead mason bee
Osmia bucephala, commonly known as the bufflehead mason bee, is a solitary bee species in the family Megachilidae native to North America. As a mason bee, it nests in pre-existing tubular cavities and uses mud to construct and seal brood cells. The species is part of the diverse Osmia genus, which includes many ecologically important pollinators. Limited specific ecological data is available for this species compared to better-studied congeners such as O. lignaria.
Osmia chalybea
Osmia chalybea is a solitary mason bee (Megachilidae) native to North America. It nests in pre-existing cavities and has been studied as a potential pollinator for orchard crops, particularly blueberries. The species serves as a host for the cleptoparasitic bee Stelis ater. It is one of several Osmia species evaluated for commercial management in agricultural pollination systems.
Osmia clarescens
Osmia clarescens is a solitary mason bee in the family Megachilidae, described by Theodore Dru Alison Cockerell in 1911. The species occurs in Central America and North America. Like other members of the genus Osmia, it is a cavity-nesting bee that constructs nests in hollow stems or pre-existing holes, sealing brood chambers with mud. Specific ecological details and distinguishing characteristics remain poorly documented in the scientific literature.
Osmia coloradensis
Colorado Mason, Colorado osmia
Osmia coloradensis is a solitary mason bee in the family Megachilidae, native to western North America. Like other Osmia species, it nests in pre-existing cavities such as hollow plant stems or holes in wood, sealing nest chambers with mud. The species is recognized as a native pollinator with documented observations across multiple western U.S. states and parts of Central America. It belongs to a genus of bees increasingly valued for orchard pollination services, though specific management practices for this species are less developed than for commercially used relatives.
Osmia cornifrons
Horn-faced Mason Bee, Horned-face Bee
Osmia cornifrons is a solitary mason bee native to Northern Asia, widely managed as an agricultural pollinator. The species was first introduced to Japan in the 1940s for apple pollination and subsequently to the northeastern United States in 1977. It is recognized by distinctive horn-like projections on the lower face of females. The bee exhibits protandry, with males emerging 2–3 days before females. It has been documented as established in Canada since at least 2017. Populations remain stable and have not shown rapid expansion compared to the accidentally introduced congener O. taurus.
Osmia dakotensis
Osmia dakotensis is a solitary bee species in the family Megachilidae, described by Michener in 1937. It is native to North America. As a mason bee, it likely nests in pre-existing cavities and uses mud to construct brood cells. Beyond its taxonomic placement and geographic distribution, specific biological details remain poorly documented in available literature.
Osmia distincta
Beardtongue scraper bee
Osmia distincta is a solitary mason bee in the family Megachilidae, native to North America. It is commonly known as the beardtongue scraper bee, reflecting its association with Penstemon (beardtongue) plants. The species was described by Cresson in 1864 and has been documented in the northeastern United States, particularly Vermont. As a member of the genus Osmia, it nests in pre-existing cavities and provisions brood cells with pollen.
Osmia foxi
Osmia foxi is a species of mason bee in the family Megachilidae, subgenus Melanosmia. It was long considered enigmatic, known only from the male holotype until its redescription in 2011, which included the first description of the female. The species is restricted to the southwestern United States and northwestern Mexico, where it occurs in montane pine-oak forest habitats. It exhibits the metallic coloration typical of many Osmia species.
Osmia gaudiosa
Osmia georgica
Georgia Mason Bee
Osmia georgica is a solitary bee species in the family Megachilidae, commonly known as the Georgia Mason Bee. It is found across North America and Central America. As a member of the genus Osmia, it is a mason bee that constructs nests using mud or other materials. The species was described by Ezra Townsend Cresson in 1878.
Osmia glauca
Osmia glauca is a species of mason bee in the family Megachilidae, originally described as Heriades glaucum by Fowler in 1899. It is native to North America and belongs to a genus of solitary bees known for nesting in pre-existing cavities and sealing brood cells with mud. Like other Osmia species, it is likely a pollinator of flowering plants, though specific ecological details remain poorly documented.
Osmia integra
Osmia integra is a solitary mason bee species in the family Megachilidae, native to North America. It is distinguished by its nesting behavior in sand dune habitats, where it constructs shallow nests. The species was described by Cresson in 1878 and includes two recognized subspecies: O. i. integra and O. i. nigrigena. Like other Osmia species, it is a native pollinator, though specific ecological details remain understudied.
Osmia lignaria
blue orchard bee, orchard mason bee, BOB
A solitary megachilid bee native to North America, widely managed for pollination of early spring fruit crops including almonds, apples, and cherries. Distinguished by metallic blue coloration, smaller size than honey bees, and unique mud-nesting behavior. Divided into two subspecies by the Rocky Mountains: O. l. propinqua (west) and O. l. lignaria (east).
Osmia lignaria lignaria
Eastern Blue Orchard Bee
Osmia lignaria lignaria is the eastern subspecies of the blue orchard bee, a solitary mason bee native to North America. It is a managed pollinator prized for its efficiency in pollinating early spring-blooming fruit trees including almonds, apples, pears, and cherries. The bee nests in pre-existing cavities such as hollow stems and beetle holes, sealing nest entrances with mud. It has experienced population declines in the eastern United States, with research ongoing into competition with non-native Osmia species and vulnerability to pesticides and parasites.
Osmia lignaria propinqua
Western Blue Orchard Bee, Blue Orchard Bee, BOB
Osmia lignaria propinqua is a solitary, cavity-nesting mason bee native to western North America, commonly known as the Western Blue Orchard Bee or BOB. It is a subspecies of the blue orchard bee and is valued as a highly efficient pollinator of early-blooming fruit trees including almonds, cherries, apples, and plums. Females carry dry pollen on the scopa (hairs) beneath the abdomen rather than on leg baskets, and they forage at lower temperatures and for more hours than honey bees. The species is managed commercially in orchards, where it is often deployed alongside honey bees to improve cross-pollination through its tendency to move between trees rather than forage systematically on single plants.
Osmia montana quadriceps
Osmia montana quadriceps is a subspecies of mason bee in the family Megachilidae, described by Cresson in 1878. As a member of the genus Osmia, it is a solitary bee that nests in pre-existing cavities and uses mud to construct brood cells. The subspecies is part of the North American fauna of native mason bees. Mason bees in this genus are valued as pollinators of orchard crops and wild plants, with females carrying pollen on specialized abdominal scopae rather than on leg baskets.
Osmia palmula
Osmia pumila
Osmia pumila is a solitary mason bee native to eastern North America. It is strongly associated with forest habitats, where it performs spring pollination of wildflowers and possibly some timber trees. The species nests in pre-existing cavities such as hollow stems or holes in wood, sealing brood chambers with mud. Research indicates it is one of the most common forest-associated bee species in the eastern United States, with populations increasing as forest cover has regrown since the early 1900s.
Osmia rawlinsi
Osmia rawlinsi is a species of solitary mason bee in the family Megachilidae. It was described by Sandhouse in 1939 and is native to North America. Like other members of the genus Osmia, it is a cavity-nesting bee that uses mud to construct and seal its nest cells. The species is poorly documented in scientific literature, with limited information available regarding its ecology, distribution, and conservation status.
Osmia ribifloris biedermannii
Osmia ribifloris biedermannii is a subspecies of mason bee in the family Megachilidae. The parent species O. ribifloris has been developed as a commercially managed pollinator of highbush blueberry. As a member of the genus Osmia, it exhibits solitary nesting behavior in pre-existing cavities and provisions brood cells with pollen. This subspecies was described by Michener in 1936.
Osmia simillima
Osmia simillima is a solitary mason bee in the family Megachilidae, native to North America. It nests in twigs, buried wood, and has been observed using oak apple galls as nesting sites. As a member of the genus Osmia, it belongs to a group of ecologically important pollinators that use mud to construct and seal nest chambers.
Osmia subfasciata
Osmia subfasciata is a solitary mason bee in the family Megachilidae, native to Central and North America. It is one of approximately 140 Osmia species present in North America. The species belongs to a genus valued for pollination services, particularly in orchard agriculture. Two subspecies are recognized: O. s. subfasciata and O. s. miamiensis.
Osmia taurus
Taurus Mason Bee
Osmia taurus is a mason bee native to eastern Asia that was accidentally introduced to North America, first recorded in Maryland and West Virginia in 2002. The species has undergone rapid population expansion across the eastern United States, with established populations now confirmed in Canada (Ontario and Quebec). Its spread has been linked to commercial shipments of the intentionally introduced pollinator Osmia cornifrons, with which it is frequently confused. Population growth of O. taurus in the Mid-Atlantic region reached 800% over 15 years, coinciding with documented declines of 76–91% in six native mason bee species.
Osmia texana
Texas Mason Bee, Texas osmia
Osmia texana, commonly known as the Texas mason bee, is a solitary bee species in the family Megachilidae. It is native to Central America and North America. As a member of the genus Osmia, it is a cavity-nesting bee that uses mud to construct and seal its nest cells. Like other mason bees, it is a pollinator of flowering plants, though specific ecological details for this species remain limited in available literature.
Panurginus
mining bees
Panurginus is a genus of mining bees in the family Andrenidae, with more than 50 described species distributed across the Holarctic region. Species occur in diverse habitats including alpine zones of Central Europe, the Siberian taiga, and steppe regions of Central Asia. Some species, such as P. herzi and P. montanus, are morphologically very similar and require quantitative measurements for reliable identification. The genus exhibits variable pollen host specialization, with individual species ranging from narrow specialists to broad generalists.
Panurginus occidentalis
Panurginus occidentalis is a species of mining bee in the family Andrenidae, first described by Crawford in 1916. The species belongs to the subfamily Panurginae, a group of solitary bees that typically nest in soil. It is native to North America.
Paranthidium
Paranthidium is a genus of bees in the family Megachilidae, tribe Anthidiini, established by Cockerell & Cockerell in 1901. The genus contains seven described species distributed in North and Central America. Members are solitary bees that construct nests using collected materials. Little is known about the biology of most species, with P. jugatorium being the most frequently observed and studied.
Paranthidium jugatorium jugatorium
Paranthidium jugatorium jugatorium is a subspecies of resin bee in the family Megachilidae, distributed across northern and central Mexico. As a member of the tribe Anthidiini, it constructs nests using plant resins and other materials. The subspecies was originally described by Thomas Say in 1824. It belongs to a genus characterized by compact, often boldly patterned bees that are active primarily during warm seasons.
Paranthidium jugatorium lepidum
Southeastern Sunflower Burrowing-Resin Bee
Paranthidium jugatorium lepidum is a subspecies of resin bee in the family Megachilidae. It is recognized by the common name "Southeastern Sunflower Burrowing-Resin Bee" and is distributed across central and western Mexico. As a member of the genus Paranthidium, it is presumed to construct nests using plant resins and to exhibit solitary nesting behavior. The subspecies designation indicates geographic variation within the broader species P. jugatorium.
Paranthidium jugatorium perpictum
Paranthidium jugatorium perpictum is a subspecies of wool-carder bee in the family Megachilidae. It belongs to a genus of solitary bees known for collecting plant fibers to line their nest cells. The subspecies is endemic to central and northwestern Mexico. Like other members of Paranthidium, it is presumed to be a solitary nester, though specific biological details remain poorly documented.
Peponapis
Squash bees
Peponapis is a genus of ground-nesting bees in the family Apidae, commonly known as squash bees. These solitary bees are specialized pollinators of plants in the family Cucurbitaceae, including squash, pumpkins, gourds, and cucumbers. The genus underwent rapid geographical expansion following the domestication and spread of cucurbit crops by humans. Peponapis pruinosa, the most studied species, has been used as a model organism for understanding the impacts of agricultural practices on ground-nesting bees and for assessing pesticide risk in agricultural soils.