Critter Catalog

What do they look like?

Pure green sweat bees are a shiny, brightly colored species of bee. They have large, black eyes and two dark wings. Pure green sweat bees average 8 mm in length. Their shimmering colors range from gold to green to blue. Female bees have 12 antennae segments, while males have 13 segments. Female bees are often larger than male bees and have pollen-collecting hairs on their back legs. (Mitchell, 1962; Short and Lucky, 2018)

• Other Physical Features
• ectothermic
• bilateral symmetry

• Sexual Dimorphism
• female larger
• sexes shaped differently

• Average length

  8 mm

  0.31 in

Where do they live?

Pure green sweat bees (Augochlora pura) are found across the eastern United States and Canada. This species ranges from Quebec and Nova Scotia to Florida and Texas. They are found from April to October. The time frame becomes longer with warmer temperatures, it goes from February to November. (Young, 2019)

• Biogeographic Regions
• nearctic
  • native

What kind of habitat do they need?

Pure green sweat bees are found in and near shady hardwood forests. Nests are commonly located under in fallen logs in forests. They may travel to nearby open areas to gather food. (Young, 2019)

• These animals are found in the following types of habitat
• terrestrial

• Terrestrial Biomes
• forest

How do they grow?

Pure green sweat bees undergo complete metamorphosis like other bees in the order Hymenoptera. Larvae hatch from eggs, then pass through several stages of growth. Once the larvae have fully matured, they begin the pupal stage. During this phase, pupae transform into adult bees. (Stockhammer, 1966)

• Development - Life Cycle
• metamorphosis
• diapause

How do they reproduce?

Males will not pursue females in flight. Instead, males wait for females to land on a flower before attempting.

Pure green sweat bees mate in the fall. After mating, male bees die. Female bees will gather food to build up fat to survive the winter in hibernation. (Stockhammer, 1966)

Unlike other bees in the family Halictidae, pure green sweat bees nest under loose bark of stumps, rotten trees, and logs. Female bees build cells out of mud and debris from under the bark. She glues the debris together with her saliva and nectar. These cells can be two or three-dimensional structures. Once a cell is complete, the female will lay a single egg into it and seal it. The time from egg to adult is 17-40 days, depending on temperature. (Moisset and Wojcik, 2020; Stockhammer, 1966)

• Key Reproductive Features
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• fertilization
  • internal
• oviparous
• sperm-storing

• How often does reproduction occur?

  Yearly

• Breeding season

  Mating occurs in the fall.

• Range age at sexual or reproductive maturity (female)

  17 to 40 minutes

• Range age at sexual or reproductive maturity (male)

  17 to 40 days

Each female builds her own nest and produces her own offspring. The last generation of females to hatch in the fall will overwinter and start their nests in the spring. Males do not contribute to nest building or food gathering. (Stockhammer, 1966)

• Parental Investment
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female

How long do they live?

The exact lifespan of pure green sweat bees is not known. The time to mature from egg to adult can range from 17 to 40 days. It is likely that females die after completing 9-12 nests. Most often there are 2-3 generations per year. Pure green sweat bees near the northernmost parts of their geographic range have fewer generations per year.

How do they behave?

As the name suggests, pure green sweat bees are attracted to the sweat of humans. They are a solitary species that prefers shady habitats. Female bees may overwinter together. Female pure green sweat bees start searching for nectar in the morning, followed by pollen foraging into the afternoon. The late afternoon is used for nest building and protecting. (Short and Lucky, 2018; Stockhammer, 1966)

As the name suggests, pure green sweat bees are attracted to the sweat of humans. They are a solitary species that prefers shady habitats. Female bees may shelter together throughout the winter. Female pure green sweat bees start searching for nectar in the morning, followed by pollen foraging into the afternoon. The late afternoon is used for nest building and protecting.

• Key Behaviors
• flies
• diurnal
• motile
• sedentary
• hibernation
• solitary

How do they communicate with each other?

Not much is known about the communication and perception of pure green sweat bees. They may use visual, chemical, and tactical perception. Chemical and tactical communication is likely. (Short and Lucky, 2018)

• Communication Channels
• chemical

• Perception Channels
• visual
• tactile
• chemical

What do they eat?

Adults feed primarily on nectar. They feed off many types of flowers and show little preference. (Young, 2019)

• Primary Diet
• herbivore
  • nectarivore

• Plant Foods
• nectar

What eats them and how do they avoid being eaten?

Female bees can sting to defend themselves and their nests. Pure green sweat bees are preyed upon by spiders, birds, and other insects. The nests of pure green sweat bees are likely impacted by parasitoid wasps. (Short and Lucky, 2018)

• Known Predators

  • Spiders
  • Birds
  • 'Other insects Arthropods'

What roles do they have in the ecosystem?

Pure green sweat bees are generalist pollinators. They collect pollen from over 40 different species of plants, including spring beauties, false rue anemones, dimpled trout lilies, slender toothworts, and star chickweeds. It may be one of the few animal pollinators of walnut. Nematodes are parasites of pure green sweat bees. The species is preyed upon by spiders, birds, and other insects. (Motten, 1986; Schemske, et al., 1978; Short and Lucky, 2018; Stockhammer, 1966)

• Ecosystem Impact
• pollinates

Do they cause problems?

As the name suggests, pure green sweat bees are attracted to the sweat of humans. The females will lick the sweat and they may sting if startled. (Short and Lucky, 2018)

• Ways that these animals might be a problem for humans
• injures humans
  • bites or stings

How do they interact with us?

Pure green sweat bees are important pollinators. They may contribute to the pollination of fields near their forest habitat. (Short and Lucky, 2018)

• Ways that people benefit from these animals:
• pollinates crops

Are they endangered?

No special statuses.

• IUCN Red List

  No special status

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Some more information...

Pure green sweat bees may also be referred to as pure gold-green sweat bees.

Contributors

Deena Hauze (author), Animal Diversity Web Staff.

References

Mitchell, T. 1962. Bees of the eastern United States. Technical bulletin (North Carolina Agricultural Experiment Station), No. 141: 1-538. Accessed May 18, 2020 at https://projects.ncsu.edu/cals/entomology/museum/easternBees.php.

Moisset, B., V. Wojcik. 2020. "The Pure Golden Green Sweat Bee (Augochlora pura)" (On-line). U.S. FOREST SERVICE. Accessed May 17, 2020 at https://www.fs.fed.us/wildflowers/pollinators/pollinator-of-the-month/augochlora_pura.shtml.

Motten, A. 1986. Pollination Ecology of the Spring Wildflower Community of a Temperate Deciduous Forest. Ecological Monographs, 56(1): 21-42.

Schemske, D., M. Willson, M. Melampy, L. Miller, L. Verner, K. Schemske, L. Best. 1978. Flowering Ecology of Some Spring Woodland Herbs.

Ecology

Short, C., A. Lucky. 2018. "common name: pure gold-green sweat bee (suggested common name) scientific name: Augochlora pura (Say 1837) (Insecta: Hymenoptera: Halictidae: Halictinae)" (On-line). Featured Creatures. Accessed May 17, 2020 at http://entnemdept.ufl.edu/creatures/MISC/BEES/Augochlora_pura.html.

Stockhammer, K. 1966. Nesting Habits and Life Cycle of a Sweat Bee, Augochlora pura (Hymenoptera: Halictidae). Journal of the Kansas Entomological Society, 39(2): 157-192.

Young, B. 2019. "NatureServe" (On-line). NatureServe Explorer. Accessed May 18, 2020 at https://explorer.natureserve.org/.