What’s this bug
We are in Missouri, woke up to let the dog out and the yard was swarming with these. When I mean swarming I mean swarming. The entire yard, the neighbors yard as far as the eye could see they were everywhere. I left at about 9 am to take my daughter to camp. The entire subdivision was covered in them!! Any ideas? When we came back at about 10 there is significantly less of them but they are still out there. They are on the west side of the house only though not the east. Maybe they don’t like the sun? Thanks
Nikki Hickman


Hi Nikki,
You have been graced with witnessing the mass emergence of a species of Mayfly in the order Ephemeroptera. Adults only live a few days, their sole purpose in life being to mate and provide food to a vasy aray of other creatures higher up the food chain, like birds, fish and predatory insects. Larval Mayflies are aquatic, and live near a water source. Mayflies also are unique in that their are two adult forms, the subimago and the reproductive adult, known as the imago. We are also including a comment letter we got on a previous posting. You have pictures of a sloughed off exoskeleton and an adult. Perhaps one of our more knowledgeable readers can clarify if the adult is an imago or reproductive adult. If you are far from the water source, we are confident this is a reproductive adult.
Further Update: (04/26/2008)
Hi Daniel,
I sent in the comment several days ago about the mayfly imago and subimago; I’m a fly fisherman, among other things, and the mayfly picture with the shed exoskeleton jumped out at me. Interestingly, fly fisherman call the subimago stage of mayflies “duns” and the imago stage “spinners”. These are British terms, and I don’t know why they picked those words. … Your website is interesting, informative and fun, all at the same time, and I read it regularly. Thanks for your help.
Bob
Clarification: (07/19/2008)
Hi Daniel,
The picture of the adult mayfly from Missouri posted on July 16 is almost surely that of an imago rather than a subimago: the wings are clear, the tails are very long, and there is a shed exoskeleton. Mayfly subimagos typically have cloudy wings and relatively short tails, although no doubt there are exceptions to the rule. This insect is probably a species of the genus Tricorythodes. Fly fishermen refer to them collectively as “tricos”. They’re tiny, and it’s a challenge to tie a fly to imitate them and to fish it successfully. Tricorythodes emergences typically occur at night or early in the morning and the subimagos rapidly metamorphose into imagos; they mate, lay eggs, and die and it’s all over by noon.
Bob
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Posted 16 July 2008
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Mayfly
Hello Bugman,
Wanted to start off by telling you what a fantastic site you have. I must say that your site has given me a new appreciation for the wonderful and beautiful world of bugs. As a person who used to think bugs were yucky, I now find myself instead seeking them out. I was hoping that I’d find something interesting for you to identify so when I found this little guy hanging out on a wall, I got excited. However, I was quite disappointed at how easily I found my answer on your site. Either way i wanted to share this gorgeous insect with you, which I am almost certain is a mayfly, in July in the San Joaquin Valley. Thanks for your time, and of course, keep up the good work!
Kelly

Goodness Gracious Kelly,
Are your Mayflies in the San Joaquin Valley on steroids? It is nearly as large as that VW Beetle.
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Posted 07 July 2008
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Mayfly???
I found this bug on my apricot tree and was really intrigued about its odd appearance. I am pretty sure it is a mayfly, but am not 100% sure. I live in northern CA about 2 1/2 hours north of Sacramento. Any help would be appreciated. Thanks.

This is a Mayfly, but your photo and letter pose a great mystery for us. The cast off skin of the aquatic naiad is visible in your photo, but we are curious how this aquatic nymph got into your apricot tree.
Explanation: (04/21/2008)
Mayflies, unlike other insects, have two adult stages (subimago and imago), and it is likely that the shed exoskeleton in the picture is that of the subimago.
Bob
Further Update: (04/26/2008)
Hi Daniel,
I sent in the comment several days ago about the mayfly imago and subimago; I’m a fly fisherman, among other things, and the mayfly picture with the shed exoskeleton jumped out at me. Interestingly, fly fisherman call the subimago stage of mayflies “duns” and the imago stage “spinners”. These are British terms, and I don’t know why they picked those words. … I enjoyed the back and forth between you and Johanna and her nails. Your website is interesting, informative and fun, all at the same time, and I read it regularly. Thanks for your help.
Bob
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Posted 20 April 2008
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Thanks, Daniel! I really enjoy spending time on your site. You have put together an incredible resource. My curiosity causes me to want to identify every bug I see that I am not familiar with. As a fly-fisherman and fly-tier, that curiosity has grown as I have many opportunities to view and identify species around the streams and lakes. Attached is a picture that I took at a northwest lake of a couple of Hexagenia Limbata Mayflies. The Hexagenia Limbata is the second largest species of mayfly. While these are more commonly found in Eastern states like Michigan and Wisconsin, there are a very few isolated rivers and lakes in the West where they hatch abundantly. The experience of being on a lake during a "Hex" hatch is incredible! The mayflies look like hundreds of miniature helicopters rising from the water all around you! And the fish loose all sensibilities (sorry, anthropomorphizing) and go nuts trying to get them!
TroutCast

Dear TroutCast,
Your personal observations and comments and excellent photo of Giant Mayflies, Hexagenia limbata, are exactly the type of submission we love posting to our site. What a welcome addition. We also found a great site called Troutnut.com to link to regaring additional information on the Giant Mayfly.
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Posted 27 August 2007
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and some mayflies
I thought you might want to take a look at this bug that I noticed in my car while driving. It was right in front of my fiancee’s face, but she didn’t see it. I stopped the car and told her to get out, and took this picture. If she had noticed it first, I’m sure we would have crashed, because let’s just say she doesn’t share my love of insects! Anyway, from the best I can tell, this is a large mayfly. I have seen some photos of the genus Hexagenia that look somewhat similar, but I know next to nothing about these. I assume the other thing in the picture is the result of a molt similar to what we see from cicadas?What do you think? Keep up the good work!
Bobby
P.s. the two images are the same, but one is rotated. I wasn’t sure which one had better feng shui.

Hi again Bobby,
Though we have never really thought of the fact that we rotate images so they will better fit the format of our site as being feng sui, that is kind of correct. Also correct on the Mayfly metamorphosis identification, though we would not commit to a genus name on this.
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Posted 29 May 2007
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another photo for you…
Dear Bugman,
Not a dead fly, but an interesting ‘phenomenon’ we saw on the wall of our house… It seems that the fly has changed it’s skin (exoskeleton?) and is waiting for the new one to dry before flying off! No idea what it is but thought it may be good for your pages. I was wondering whether the wings are ‘renewed’ at the same time or not - but there seem to be shrivelled wings on the old ‘case’… Best wishes, keep up the good work…
Abdullah Eyles
Ceyhan, Turkey

Hi Abdullah,
Members of the order Ephemeroptera are known as Mayflies in the U.S. We don’t know if they have an equally descriptive name in Turkey. Larval Mayflies are aquatic, so you must have a water source, pond or fountain, in the very near vicinity. Mayflies have incomplete metamorphosis. The aquatic nymphs, or naiads, have no wings, and after the final molt, the winged adult emerges. Mayflies are short lived as adults and do not feed.
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Posted 21 April 2007
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Is this a dragonfly?
In the past few days I’ve seen lots of these yellow insects hanging around outside work. Today I saw this one that had just emerged from its former body and had to take a closeup photo of the two. It is an awesome looking bug; is it a dragonfly? Thanks,
Paul Becker
(found in Chesterfield, Missouri)

Hi Paul,
Don’t let the name fool you. Even though it is September, this is a Mayfly. Like dragonflies, the aquatic nymphs are known as Naiads. Mayflies do not feed as adults and sometimes appear in great numbers, only to disappear in a few days to return the following year.
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Posted 06 September 2006
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May Fly Transformation
Here is a picture of some sort of may fly freshly coming out of its nymph shell. Found in the mountians of West Virginia. Thanks
Jed

Thanks for your image Jed, even though our posting is late.
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Posted 02 September 2006
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fours and fives in PA
Hello!
We are a class of 4 and 5 year olds in PA. You have helped us before identifying bugs and we hope you can help again. We search our playground daily for bugs, photograph them and then hang them on our wall [we included a photo]. We have then been using your site to help us identify what we find. We have figured out most of them now [hopefully correctly] but are stumped on a couple. THANK YOU VERY VERY MUCH BUGMAN!
Fours and Fives in PA


Hi again Fours and Fives,
Both of these photos are of Mayflies. The photos look so nice together. Your BugWall is pretty awesome.

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Posted 28 August 2006
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Strange Fly
What’sThatBug.com:
I recently encountered this large fly on my honeymoon in Alexandria Bay, in the Thousand Islands region of New York. It was sedately sunning on my balcony until I started trying to get close enough to take a macro mode shot. It began lifting it’s mandibles and whip-like in threatening(or inquisitive) ways at me. It was quite a show, and if the display was for purposes of intimidation I would say it suceeded! I should’ve taken a quick movie clip of it, but these pics will have to suffice…. So, what’s that bug?
-Ben H.
P.S…. And, no, I didn’t kill it! Though if it were inside I probably would have. Just to prove I wasn’t scared.

Hi Ben,
Mayflies in the order Ephemeroptera, are totally harmless. Adults do not even possess mouthparts as they only live a few days and their sole purpose is to mate, (except to provide food to other creatures including trout).
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Posted 07 August 2006
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New species of a water bug?
Hey bug guys,
Here on vacation in Minnesota, we spend plenty of time in lake Kabekona, the lake we’re staying at. However, picking up and moving rocks today, this little bugger somehow found his way to my finger, just kind of hung on but wasn’t really holding on too tightly to me. He acted like a fish out of water on my finger, didn’t move or do anything, I thought I accidentally killed it trying to find a frisbee to put water in so it would be happy. After putting it back in some water, it perked up and swam around using it’s 6 legs and 3 tails, awkward looking little guy.. I was hoping you guys could tell us if this is maybe a parasite or just another weird bug, he was very small only about a quarter of an inch, perhaps a little less. Thanks for your time, hope to hear back from you soon!
Cheers,
Becky Studley

Hi Becky,
This is an immature Mayfly, known as a Naiad. Mayflies belong to the order Ephemeroptera. Adults do not feed and only live a few days. Naiads feed on algae and microscopic organic debris.
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Posted 19 July 2006
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Can you identify?
This bug landed on the outside of my office window a while back and I’ve saved the picture ever since hoping to find out what it was. I’ve never seen a bug quite like this. Any ideas?
Jenn

Hi Jenn,
Even though this is a Mayfly, they appear in other months as well.
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Posted 27 March 2006
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What is this bug?
Good Day,
Love the site… great fun for a fly tier like
myself! A friend from Singapore found many of the following insect on a resevoir there and wondered what is was… any ideas? Thanks!
Christopher

Hi Christopher,
This is some type of Homopteran, we believe. We are still checking though. Eric Eaton came to the rescue: ” Wondering now if the Homopteran from Singapore might actually be some kind of mayfly. Looks like it might have had two tails that broke off, and at least some mayflies have only one pair of wings, which this insect seems to have. Lastly, the fact that it was found by a fly fisherman floating in a reservoir just about seals the deal”
Update: (11/02/2007)
Hi guys… Hi there,
LOL, this is indeed a mayfly and not a Homopteran. This species has very short tail (not broken) but similar species up north (Malaysia and Thailand) do have longish tails. I have read elsewhere that identification is in order. This species burrow and feed on drift wood , the aquatic nymphs are favourite food for many types of fishes found in the reservoirs. I have seen the females ascending from sky in the morning and land on the water, and start fluttering (more like vibrating and sending ripples) its wing and dragging the egg sack attach via a strong silk like stuff to the end of the tail. It will keep fluttering until it attaches the egg sack to any structure dotting the shorelines and die there. The egg sag will absorb water and within days grow bulkier and look very much like frog eggs! Once the nymphs leave the clear jelly sack they start to look for drift wood to burrow and feed. Singapore is an seasonal country so this species lay eggs almost every morning with no particular peak season. I have been trying to find literature on this species to no avail for the last 2 decades. Save the short tail, they have very Mayfly like body anatomy (side fins along abs), which I therefore told my friends as much. That’s the story
Strangely I have yet to see the hatching and mating, only the spent stage as mentioned above. Where do you think I should look for the actions? I never see any shack so far! What a mystery Mayfly…. Regards,
Yu Hock
Hi Yu Hock,
Thanks for all the valuable information on this unusual Mayfly. Sadly, we are unable to provide you with any additional information.
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Posted 22 September 2005
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I was vacationing last week in Salt Creek, NY along the Wappinger Creek and took a double portrait of this bug which was resting nears it’s newly shed exoskeleton & just thought I would share.
Barry Hayman
Washington, D.C

Hi Barry,
What a wonderful photo of a newly metamorphosed Mayfly. Despite their name, Mayflies mature during other months as well. Adults only live a few days, long enough to mate..
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Posted 15 August 2005
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More unidentified critters
I photographed three of these on recent trips to Arkansas and one at a local park here in Southern Cal. Hoping you could help me identify them.
Thanks
Rus

Hi Rus,
This Mayfly is one of your Arkansas critters. Mayflies belong to the Order Ephemeroptera which alludes to the fact that they only live a day, though some live several days. May is not the only month they are found. When they emerge as adults, they usually do so in great numbers. Their nymphs or naiads are aquatic. Your photo is stunning, and will result in a new page for our site.
Identification Update:
(08/01/2005) The mayfly is a male subimago of the genus Hexagenia. The nymphs are burrowers in mud and debris in clean streams and rivers. This one is related to the mayflies that occasionally form huge emergence swarms on the upper Mississippi and the Great Lakes. Hope this helps.
Sincerely,
R. Wills Flowers
Center for Biological Control
Florida A&M University
Tallahassee, FL 32307
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Posted 28 July 2005
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