Currently viewing the category: "Sweat Bees"

Subject: Armored fly
Location: uruguay
December 9, 2016 10:29 am
Hello, this little guy looked very tough, brilliant green, and really loud when airborne. Thanks
Signature: Louis

Sweat Bee

Sweat Bee

Dear Louis,
Unfortunately, the most specific we can get with your identification is to inform you that this is a Sweat Bee in the family Halictidae.  Though your species is most likely different from North American species, you can still see BugGuide for information on the family.  We suspect your individual is a Metallic Green Sweat Bee in the genus
Agapostemon based on its resemblance to North American species pictured on BugGuide.

Subject: Mettalic Green Bee, Nest and Guard
Location: Toronto Canada
June 29, 2016 6:35 pm
Could not resist sending you one more photo of my bees. hope you do not mind.
Signature: Scott Morrow

Metallic Green Sweat Bees and Nest

Metallic Green Sweat Bees and Nest

Hi again Scott,
This new image of Metallic Green Sweat Bees,
Agapostemon virescens, is a marvelous addition to the previously sent images, and it is greatly welcomed on our site.

Subject: Metallic Green Bee or Sweat Bee
Location: Toronto Canada
June 16, 2016 9:39 am
I have had a nest in my garden for about 6 years (it is a no dig zone). Thought I would share a photo with you. Great site! Have an awesome summer.
Signature: Scott Morrow

Metallic Green Sweat Bee and Nest

Metallic Green Sweat Bee and Nest

Dear Scott,
We love your image of a Metallic Sweat Bee hovering near her nest so much we are going to feature it this month.  According to BugGuide, Sweat Bees in the family Halictidae are:  “typically ground-nesters, with nests formed in clay soil, sandy banks of streams, etc. Most species are polylectic (collecting pollen from a variety of unrelated plants).”  We also want to commend you on your “no dig zone” which will protect the young that are developing in the nest.  We wish more of our readers were as sensitive to the environment as you are.

Wow…i am honoured!!
There is a ‘but’ though…I have been seeing small red and black bees landing on the nest site. To the best of my research they may be trying to attack the nest of the green bees (cleptoparasites I think they were called). I don’t like to alter how real life happens but I love my green bees…any suggestions?

Hi Scott
We are sorry to hear about your disappointment.  We are hoping you are able to provide an image of the “mall red and black bees.”  They sound like they might be members of the genus
Sphecodes, based on this BugGuide image.  According to BugGuide:  “Cleptoparasites, usually of other Halictinae.”

My apologies if it came across as being disappointed. I am very happy in fact.
I will try to get a picture but they are quite small and fast to fly away.
Thanks again.

Hi Scott,
Sometimes electronic communication leads to misunderstandings.  We interpreted your love for your green bees to mean you were disappointed that they were being Cleptoparasitized by the black and red relatives.  On a positive note, we doubt that all of the Green Sweat Bee young will be lost.  We eagerly await a potential image of the Cleptoparasite.

Update:  June 24, 2016
Hi Daniel
This is the best I managed to get. The Green Bee guard is blurred but can be seen in the centre of the photo.
Even though I love my Green Bees I will not harm or harass the red ones as this is what nature does.
Be well and have a great buggy summer.

Cleptoparasite Bee

Cleptoparasitic Cuckoo Bee

Hi Scott,
Thanks so much for the update.  We are confident that the red bee is a Sweat Bee in the genus
Sphecodes which is well represented on BugGuide, though we would not entirely rule out that it might be a Cuckoo Bee, Holcopasites calliopsidis, based on the images posted to Beautiful North American Bees.  That would take far more skill than our editorial staff possesses, though according to BugGuide it is a diminutive “5-6 mm”.  We will contact Eric Eaton to get his opinion.  While we feel for your affection for the Metallic Green Sweat Bees, we do not believe the presence of the red cleptoparasitic  Bees will decimate the population of the green bees.  Nature has a way of balancing out populations, and when food is plentiful, populations flourish.  Your “no dig zone” is diversifying in its inhabitants.  To add further information on cleptoparasitism, we turn to BugGuide where it defines:  “cleptoparasite (also kleptoparasite) noun – an organism that lives off of another by stealing its food, rather than feeding on it directly. (In some cases this may result in the death of a host, for example, if the larvae of the host are thereby denied food.”

Correction Courtesy of Eric Eaton
The cleptoparasite is a Nomada sp. cuckoo bee.  The host bee is Agapostemon virescens, by the way.  Never seen a turret on their nest entrance that was so tall!  Nomada is a genus in the family Apidae (formerly Anthophoridae).

Ed. Note:  When we first responded to the Cleptoparasite response, we suspected we might be dealing with a Cuckoo Bee and we prepared a response with BugGuide quotes including “Wasp-like, often red or red and black and often with yellow integumental markings” and “cleptoparasites of various bees, primarily Andrena but also Agapostemon and Eucera (Synhalonia) (these are usually larger than the Andrena cleptoparasites). (J.S. Ascher, 23.iv.2008)  males mimic the specific odors of the host females and patrol the host nest site.”  We were going to console Scott with the information that his Green Sweat Bees were most likely being scoped out by male Cuckoo Bees who had not net mated with a female, the real cleptoparasite.  Next time we will trust our first impression.


Subject: Unknown Very Small Bee Species
Location: Lamar county, South Mississippi
December 25, 2014 6:14 pm
Above is a link to a video I posted of an unidentified bee species I found in my back yard one day. I realize the video isn’t the best quality but it’s all I have. They were so small once I left the area I couldn’t find them again to obtain a specimen. I can tell you my finger seen in the video is 2 cm wide, exactly, if you can use that for size reference.
If you pause it near the end you can get a decent profile of it and it’s characteristics. They lived in a small hole which was guarded by the abdomen of a colony member. They appeared to be gatherers but were so fast I couldn’t see what they were bringing back. My first impression was that I was looking at a queen fire ants (Solenopsis invicta) ready to swarm as the bees had amber, shiny bodies just like fire ants. But their flight characteristics said bee to me. They weren’t aggressive when I probed the opening with a small piece of grass, they just removed it and continued to keep the entrance sealed with an abdomen.
I have passed this video around to a few local entomologists and they keep telling me bees don’t get that small and they can’t tell without a specimen. All the research I have done has produced similar looking insects like Sphecodes but I can’t find any that fit into this size range.

Thank you.
Signature: Steven Cimbora

Bee or Wasp???

Probably Sweat Bee

Dear Steven,
Your video shows what appears to be a Mining Bee in the family Andrenidae.  According to BugGuide:  “Many small, ground-nesting bees observed in areas of sandy soil are members of the family, Andrenidae. Characteristics of this family (of which there are approximately 3000 species) are: Small size, 20 mm, (or smaller) brown to black in color, and nesting in a burrow in areas of sparse vegetation, old meadows, dry road beds, sandy paths. Although the nests are built in close proximity of one another, the bees are solitary (each female capable of constructing a nest and reproducing). Many species are active in March and April when they collect pollen and nectar from early spring blooming flowers. The female bee digs a hole 2-3 inches deep excavating the soil and leaving a pile on the surface. She then digs a side tunnel that ends in a chamber (there are about 8 chambers per burrow). Each chamber is then filled with a small ball of pollen and nectar. An egg is laid on the top of each pollen ball and the female seals each brood chamber. The emerging larval bees feed on the pollen/nectar ball until they pupate.”  We are shocked that your local entomologists have no knowledge of these native, small, ground-nesting Mining Bees.

Head of a Mining Bee preparing to exit

Head of a Mining Bee preparing to exit (from our archives)

Thank you for the quick response.
I just wanted to point a few things out that run contrary to the Mining Bee’s description based on my personal observations of them.
I observed fellow nest members guarding the entrance with their abdomen, as seen in the video.
The nest entrance is perfectly clean of any mounding or tunnel waste and I observed more than one bee leave and return to the entrance. A few times there were several hovering near it waiting to enter.
The size range of 20 mm or smaller is starting out at the width of my finger, seen in the video which is 20mm or 2 cm wide. I would estimate their size at about 5 mm at best and that was the bigger ones.
As you watch the very beginning of the video, right before I put my finger in frame, you will see one depart then another come to the entrance and block it with it’s abdomen. This is not a solitary bee as the mining bees are described as being. They also appeared to lack the pollen brush associated with Mining bees.
Thank you for the effort and if I can ever find them again I will definitely get a specimen.
Steven Cimbora

Thanks for getting back to us Steven.  We have tagged the posting as Unidentified and we have included a screen shot from the end of your video.  Perhaps one of our readers has an idea what Hymenopteran this might be.

Update:  January 4, 2015
Mr. Marlos,
I am providing a new link to some more footage of the unknown bees I found in my back yard. There is much more footage of their activity and it is stabilized. It also shows the presence of more than one bee occupying the nest at a time (Entrance guard) and better footage of their flight characteristics.
I went ahead and scaled some screen shots to try and get a better measurement of them and I came up with approximately 3.2 mm in length. I did this by scaling a screen shot of my finger until it measured the same as actual, using Gimp2 software to measure with. I then took a screenshot of the bee in flight and scaled it to the same dimensions and then measured it. The opening measured approximately 1.1 mm.
You might also find better images to capture and post in this footage as well.
Thank you for your time.
Steven Cimbora

Subject: Green Orchid Bee
Location: 76016 Arlington, TX
November 29, 2014 2:50 pm
This was taken today in Arlington, TX. We’ve seen several of these today humming around the garden. Temps are unseasonably warm, but will cool down tomorrow.
Signature: Lisa Parisot

Metallic Green Sweat Bee

Metallic Green Sweat Bee

Dear Lisa,
To the best of our knowledge, the Green Orchid Bee is not found in Arlington, Texas.  It is an introduced species and according to BugGuide it is a member of a:  “neotropical group, with 1 sp. established in so. FL and recorded from southernmost TX (Brownsville)”
  This is a Metallic Green Sweat Bee in the subfamily Halictinae, and you can read more about them on BugGuide where it states:  “Most species nest in burrows in banks or in the ground (Augochlora uses partially rotten logs). Some are primitively eusocial; in such cases usually a female guards the entrance to the burrow by plugging it with her head. Generally the main burrow is vertical; it sends horizontal branches, each branch ending in a solitary cell.”  It can be very difficult to identify Metallic Green Sweat Bees to the genus or species level from images. 

Subject: green bee
Location: Denver CO
June 8, 2014 12:17 pm
There has appeared in my buffalo grass lawn several dirt mounds that at first seem to be larger steep ant hills, but today I saw these colorful bees going in and out. Are they natives?
Signature: Jeanette

Metallic Sweat Bee

Metallic Sweat Bees

Hi Jeanette,
These beautiful, little, native bees are known as Metallic Sweat Bees, most likely in the genus
Agapostemon, based on images posted to BugGuide.  Of the subfamily Halictinae, BugGuide notes:  “Most species nest in burrows in banks or in the ground (Augochlora uses partially rotten logs). Some are primitively eusocial; in such cases usually a female guards the entrance to the burrow by plugging it with her head. Generally the main burrow is vertical; it sends horizontal branches, each branch ending in a solitary cell.”  One of your images illustrates a Metallic Sweat Bee flying toward a hole that has its opening plugged by the head of another bee.

OK, I guess I have seen both small and larger sweat bees in the yard.  I’ll try to get some better photos.  I’m seeing several different kinds of bumblebees also.
Thank you Daniel,

Metallic Sweat Bee

Metallic Sweat Bee

Wonderful Daniel!  I noticed that each opening of the three or four there would often have a bee in it, I kept waiting to try to get a good picture, but they would duck back down.  I have lots of mostly native flowers blooming in my yard right now, it is delightful to get native insects too.
I always thought sweat bees, or what we called sweat bees, were not as large as these.  These are closer to the size of honey bees ( though these in the picture are smaller than honey bees) .  Sorry I didn’t have anything to compare it to in the picture.
Thank you for your good work,

Hi Jeanette,
Some species of Sweat Bees are quite small.  Bee Informed lists their size range as between 1/4 and 3/4 inch.