Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfamily Apoidea. They are currently considered a clade, called Anthophila. There are over 20,000 known species of bees in seven recognized biological families. Some species – including honey bees, bumblebees, and stingless bees – live socially in colonies while most species (>90%) – including mason bees, carpenter bees, leafcutter bees, and sweat bees – are solitary.
Halictidae is the second-largest family of bees with nearly 4,500 species. They are commonly called sweat bees, as they are often attracted to perspiration. Halictid species are an extremely diverse group that can vary greatly in appearance. These bees occur all over the world and are found on every continent except Antarctica. Usually dark-colored and often metallic, halictids are found in various sizes, colors and patterns. Several species are all or partly green and a few are red, purple, or blue. A number of them have yellow markings, especially the males, which commonly have yellow faces, a pattern widespread among the various families of bees. The family is one of many with short tongues and is best distinguished by the arcuate basal vein found on the wing. Females in this family tend to be larger than the males. They are the group for which the term 'eusocial' was first coined by entomologist, Suzanne Batra.
Halictus rubicundus, the orange-legged furrow bee, is a species of sweat bee found throughout the Northern Hemisphere. H. rubicundus entered North America from the Old World during one of two main invasions of Halictus subgenera. These invasions likely occurred via the Bering land bridge at times of low sea level during the Pleistocene epoch.
Lasioglossum malachurum, the sharp-collared furrow bee, is a small European halictid bee. This species is obligately eusocial, with queens and workers, though the differences between the castes are not nearly as extreme as in honey bees. Early taxonomists mistakenly assigned the worker females to a different species from the queens. They are small, shiny, mostly black bees with off-white hair bands at the bases of the abdominal segments. L. malachurum is one of the more extensively studied species in the genus Lasioglossum, also known as sweat bees. Researchers have discovered that the eusocial behavior in colonies of L. malachurum varies significantly dependent upon the region of Europe in which each colony is located.
The genus Agapostemon is a common group of Western Hemisphere sweat bees.
Augochlora leptoloba is a species of sweat bee in the genus Augochlora and the extinct monotypic subgenus Electraugochlora.
Within the insect order Hymenoptera, the Halictinae are the largest, most diverse, and most recently diverged of the four halictid subfamilies. They comprise over 2400 bee species belonging to the five taxonomic tribes Augochlorini, Thrinchostomini, Caenohalictini, Sphecodini, and Halictini, which some entomologists alternatively organize into the two tribes Augochlorini and Halictini.
Halictus ligatus is a species of sweat bee from the family Halictidae, among the species that mine or burrow into the ground to create their nests. H. ligatus, like Lasioglossum zephyrus, is a primitively eusocial bee species, in which aggression is one of the most influential behaviors for establishing hierarchy within the colony, and H. ligatus exhibits both reproductive division of labor and overlapping generations.
Megalopta genalis is a species of the family Halictidae, otherwise known as the sweat bees. The bee is native to Central and South America. Its eyes have anatomical adaptations that make them 27 times more sensitive to light than diurnal bees, giving it the ability to be nocturnal. However, its eyes are not completely different from other diurnal bees, but are still apposition compound eyes. The difference therefore lies purely in adaptations to become nocturnal, increasing the success of foraging and minimizing the danger of doing so from predation. This species has served as a model organism in studies of social behavior and night vision in bees.
Lasioglossum cressonii is a species in the sweat bee genus Lasioglossum, family Halictidae. Halictidae exhibit eusocial hierarchy behavior which is interesting given that eusociality in this group is hard to evolve and easy to lose. L. cressonii is found throughout North America. L. cressonii have been shown to be important pollinators for apple trees and many other North American native plants.
Lasioglossum figueresi, formerly known as Dialictus figueresi, is a solitary sweat bee that is part of the family Halictidae of the order Hymenoptera. Found in Central America, it nests in vertical earthen banks which are normally inhabited by one, though sometimes two or even three, females. Females die before their larvae hatch. It was named after José Figueres Ferrer, a famous Costa Rican patriot, and studies of its behavior are now general models for social behavior studies.
Bombus pauloensis is a neotropical bumblebee, formerly known as Bombus atratus, that is found throughout regions of South America, including Colombia, Ecuador, Brazil, and Argentina. It lives in social colonies that include a founder queen/queens, workers and brood. B. pauloensis is somewhat unusual because of its potential to oscillate between polygynous and monogynous nesting cycles. Bombus pauloensis was the first species in the genus Bombus that was discovered to display such polygynous nesting patterns. The polygynous nesting cycles lead to certain specific types of behavior including queen-queen aggression. Nests can also be perennial, which is a characteristic rarely found in other bumblebees. B. pauloensis can be helpful to agricultural because of their ability to pollinate different species of plants. B. pauloensis has been found to occupy a range of geographic areas and climates throughout South America. Colonies have the ability to thermoregulate nests and keep them a little bit warmer than the outside environment. Foraging workers use muscle contractions to maintain stable temperatures and coupe with seasonal and daily fluctuations in temperature.
Lasioglossum aeneiventre, also known as Dialictus aeneiventre, is a social sweat bee and is part of the family Halictidae of the order Hymenoptera. Found in Central America, it nests mostly on flat ground though sometimes in vertical banks. It is often compared to L. figueresi.
Augochlora pura is a solitary sweat bee found primarily in the Eastern United States. It is known for its bright green color and its tendency to forage on a variety of plants. Inhabiting rotting logs, this bee can produce up to three generations per year. Both males and females have been observed licking sweat from human skin, most likely seeking salt
Halictus sexcinctus, commonly referred to as the six-banded furrow bee, is a species of sweat bee found throughout Europe and as far east as Asian Turkey and Iraq. The H. sexcinctus can be easily confused with the closely related species, Halictus scabiosae, due to very similar morphological features. H. sexcinctus show a social polymorphism in which different colonies can exhibit solitary, communal, or eusocial structure. Due to this large variance in social organization, it was suspected that it was not one species at all, but rather multiple, cryptic species. However, genetic analysis was able to confirm these varying populations as one species. H. sexcinctus will forage from multiple flower species, but prefers plant species with wide-open flowers. Their nests can be found dug into the ground in loamy or sandy soil.
Dialictus is a subgenus of sweat bees belonging to the genus Lasioglossum. Most of the members of this subgenus have a metallic appearance, while some are non-metallic. There are over 630 species worldwide. They are commonly found in the Northern Hemisphere and are found in abundance in North America. Members of this subgenus also have very diverse forms of social structure making them model organisms for studying the social behavior of bees.
Augochlorella is a genus in the bee family Halictidae, commonly called sweat bees. They display metallic coloration, ranging from reddish to gold to bluish green, as is typical for other genera in the tribe Augochlorini.
Halictus confusus, the southern bronze furrow bee or confused sweat bee, is a species of sweat bee in the family Halictidae. It is a primitively eusocial bee species found in open habitats in Eurasia and North America.
Augochloropsis is a genus of brilliant metallic, often blue-green, sweat bees in the family Halictidae. There are at least 140 described species in Augochloropsis.
Megalopta is a widespread neotropical genus of bees in the tribe Augochlorini in family Halictidae, known as the sweat bees. They are the largest of the five nocturnal genera in Augochlorini. Most have pale integumentary pigmentation, and all have large ocelli, most likely a feature of their nocturnal behavior. They live in tropical Central America and the entirety of South America. The subgenus Noctoraptor is cleptoparasitic. They are not known from the fossil record.
