The Halictidae family is a diverse bee classification comprising almost 4,500 species distributed globally. They are the second largest family of bees and are commonly called sweat bees.
Halictids come in many shapes and sizes, although many are slender and dull or metallic black. A small number of species have metallic blue or green bodies. Male halicdids have no hairs on their hind tibia and are slimmer than females.
- Most of the female bees collect pollen on their hind legs. A smaller number of genera are kleptoparasites, parasitic insects living off food sources from other species.
- Halicdids are classified by their finger-like, hairless lacinia located further up the maxillary tube than other bee families. They have short tongues and typically have a strongly curved basal vein, and females have a narrow pseudopygidial area.
- Members of the Halictidae Bee Family typically nest underground. They burrow into soft, rotting wood, river banks, or clay.
One of the fascinating aspects of Halictidae is their varying degrees of social behavior. The family exhibits a broad spectrum of social structures, ranging from solitary nesting to complex eusociality, similar to honey bees, where a single queen lives with many workers.
|All continents except Antarctica
|Number of species
|Halictinae, Raphitinae, Nominae, Nomioidinae
Some species also display communal living, where multiple females share a nest, but each cares for her own offspring.
Halictidae bees play an essential role in pollination. Despite their small size, they contribute to pollinating a variety of plants, including crops, thus playing a vital role in maintaining biodiversity and agricultural production.
Tip: We summarize all seven bee families here.
The Halictidae family comprises the Halictinae, Rophitinae, Nomiinae, and Nomioidinae subfamilies.
The Halictinae are the largest subfamily within the Halictidae, comprising over 3,500 species in 50 genera. They are found on every continent except Antarctica.
Most male and female halicdids have a strongly curved basal vein and a narrow pseudopygidial area.
They exhibit various social structures, from solitary nesting to communal and eusocial living.
The cells within Halictinae nests are often lined with a waxy substance. Researchers believe it is produced by the bee’s Dufour’s gland, located in its abdomen.
Augochlora: also known as the green sweat bee, the Augochlora is a visually striking bee known for its bright, metallic green or purple coloration. Located in North, Central, and South America, they are solitary insects that often nest in rotting wood.
Augochlorella: small bees found in the Americas, this genus is primarily social. Their nests are underground with a queen and several workers helping with work.
Megalopta: known as the “nocturnal bee,” Megalopta is a fascinating genus native to tropical regions. Unlike most bee species, some Megalopta can fly at night, demonstrating an adaptation to forage under low-light conditions. They are mostly pale in color and nest in hollowed-out twigs.
Agapostemon: are primarily found in the Americas and have metallic green or blue coloration. Their metasoma is banded yellow and black, similar to a yellowtail wasp.
Caenohalictus: a genus that is widely varied in appearance; many are metallic green, purple, or blue with red highlights. Found in Central and South America, these bees usually have exceptionally hairy eyes to check the wind direction.
Halictus: a widely distributed genus found in most parts of the world, these bees are mostly black or greenish. They enjoy temperate climates and often live in eusocial nests.
Lasioglossum: the largest genus of almost 1900 species, with a wide global distribution. Species in this genus exhibit a broad range of social behaviors, from solitary to eusocial. Some Lasioglossum species are particularly cold-tolerant and may live in Arctic regions. Most bees in this family are small with black, brown, or dull metallic bodies.
Sphecodes: a genus made up of almost 300 species of cleptoparasitic or “cuckoo bees.” They lay eggs in the nests of other bees, and their larvae consume the host’s pollen stores. They have a distinctive, almost wasp-like appearance, often reddish or black. These bees lack the dense body hair seen in most others.
The Rophitinae have antennae close to their face. There are over 250 species that typically have specific floral preferences.
Dufourea: comprising 170 species, the Dufourea are oligolectic, specializing in one pollen source. They are dark brown to black, although a few have bright metallic bodies. Dufourea live in the northern hemisphere but won’t tolerate cold climates.
Systropha: are known for collecting pollen all over their body surfaces. They specialize in collecting pollen exclusively from Convolvulaceae. Their heads look small relative to the rest of their body.
Xeralictus: a group of just two large bees that inhabit the arid regions of the southwestern United States and Mexico. These bees are adapted to desert life and only feed from plants in the family Loasaceae.
The Nomiinae subfamily lives on all continents except South America and Antarctica. There are 600 species in this subfamily; they often build nests with vertical cells in clusters.
Nomia: also known as striped sweat bees, are found worldwide and are particularly well-known for their distinctive, bright, metallic blue or green coloration and abdominal striping. Many species exhibit communal nesting, where multiple females share a nest, but each cares for her own offspring.
Dieunomia: a small genus of medium-sized bees with red markings or large black bees. They specialize in pollen collection from the Asteraceae.
Lipotriches: a diverse genus of bees, particularly abundant in the Australasian and Indomalayan regions. One of their notable characteristics is their hind leg morphology, specifically the modification of the tibia and basitarsus into a broad, flattened surface for carrying pollen.
Pseudapis: a small genus of bees found in southern Europe and Africa. There are 50 species in the Pseudapis subfamily, living in diverse habitats, from tropical rainforest to semi-arid land.
The Nomioidinae subfamily is a group of fewer than 100 species in three genera. These small bees are metallic in color with pale markings.
Nomioides: a genus of metallic and yellow bees with tiny bodies. They may nest in the vacated brood cells of larger bees. They are communal bees that live in dry regions with sandy soil.
Commonly asked questions
Why are they called sweat bees?
Sweat bees get their name from their attraction to the salt in human perspiration. They often land on people to lick off sweat but rarely sting.
Are Halictidae bees dangerous?
Halictidae bees are generally not dangerous. While they can sting, they are usually non-aggressive and only do so when threatened.
Where do Halictidae bees live?
Most Halictidae bees are ground-nesters, digging nests in bare or sparsely vegetated soil. They can be found in a variety of habitats worldwide.
Are Halictidae bees social or solitary?
It depends on the species. Some Halictidae bees are solitary, while others form social colonies. Some species can switch between being social and solitary, depending on environmental conditions.
Did you know? Halictidae fossils were discovered in amber, estimated between 96 and 75 million years old!
Interesting Halictidae research
We’ve summarized some interesting research related to the Halictidae bee family.