Are Dobsonfly Dangerous? How To Get Rid Of Dobsonflies?

Dobsonflies are aquatic insects that spend nearly all their lives in water. But when they come out – are Dobsonfly dangerous? Their huge size and pincers certainly indicate so, but let’s be sure.

Huge pincer-like jaws on a giant insect are a clear indicator of how dangerous it is, right? Wrong.

The jaws may look dangerous, but the bigger the jaws are, the more effort it takes to generate a sharp, biting force.

Dobsonflies are the best example of this. These insects have extremely long jaws, but surprisingly, they can barely cause any damage to humans through their bites.

But the same is not true for all kinds of dobsonflies. Confused? Well, don’t be. In this article, we will discuss which dobsonflies can hurt humans and how dangerous they are.

Are Dobsonfly Dangerous
Female Dobsonfly

What Are Dobsonflies?

Dobsonflies are one of the largest insects found in various regions of North America. They have pincer-like mandibles that can almost grow up to an inch in length.

However, if you look closely, adult males have comparatively bigger mandibles than females. This gives them a scarier appearance.

The various species of dobsonflies are aquatic insects; they prefer to stay near clean water bodies.

Also, they are nocturnal in nature and are active throughout the spring and summer.

If we exclude the size of the jaws, an adult dobsonfly can easily range from 2-4 inches in length. The Eastern Dobsonfly has an enormous wingspan of 5 inches.

The overall appearance of the body adds to the frightening factor. They are usually dark in color and have grayish-brown wings with distinct vein-like patterns.

Male Dobsonfly

Are Dobsonfly Dangerous To Humans?

Male adult dobsonflies might look fearsome with their enormous mandibles, but these jaws are just for show.

The chewing muscles are not strong enough to transfer a strong enough force to the tip of the mandibles to generate a strong bite force.

The female has shorter mandibles and can hurt humans by biting.

Can They Bite Or Sting?

Yes, they can bite, but as mentioned above, the males are not capable of delivering painful bites. The female dobsonflies have smaller jaws and can generate enough biting force to break past the human skin and trigger pain.

Are They Poisonous?

No, dobsonflies are not poisonous. Yes, the bites from the female can be a little too painful to handle, but they won’t show any long-term fatal effects on your body.

Are They Dangerous To Pets or Other Animals?

No, these types of insects are not harmful to pets. The bites can be an alarming factor here, but they won’t have any long-term effects.

Since these insects live mostly around clean aquatic bodies, the chances of your pet encountering one are less.

Are Dobsonfly Larvae Dangerous To Humans?

Larvae of dobsonflies are called hellgrammites. These aquatic insects are underwater predators and are found in clean and cool bodies of water.

Hellgrammites prefer to hunt in high water currents. Unlike adult males, hellgrammites have small and sharp pincers.

Adding to that, they are blessed with strong chewing muscles that help them to generate strong biting forces.

Hellgrammite

This means dobsonflies, during their larval stage, can hurt humans through their bites.

But again, these bites are not poisonous, and moreover, you are unlikey to meet one unless you steup into water.

Symptoms of Larval Bites?

When a hellgrammite bites, you will feel a strong surge of pain near the wound. The bites are strong enough to cause bleeding, irritation, swelling, and redness.

Thankfully, these symptoms are temporary; the pain will subside quickly.

What To Do If You Get Bitten?

If you get bitten by a dobsonfly, there is no need to panic. Yes, you will feel pain, but it won’t last long. Wash the wound with clean water and apply some antiseptic to avoid allergic reactions.

How To Get Rid Of Dobsonflies?

We have already mentioned that these aquatic insects are not dangerous for humans. Therefore if you find them near your house, it is okay to leave them be.

They won’t cause any damage, and since they have a short life cycle as adults, they will disappear quickly.

Also, dobsonflies prefer to lay egg masses near water bodies. The chances of them laying eggs indoors are close to zero.

If you are hell-bent on driving them out instantly, you can use the and powdered insecticide.

Create a solution of it by mixing an ounce of the insecticide with one-gallon water. Put the solution in a spraying bottle and sprinkle it on areas where you spot these insects.

Also, they are attracted to light sources. Therefore try to keep the porch lights off at night to avoid them.

Western Dobsonfly

Frequently Asked Questions

What Is A Dobsonfly Good For?

Dobsonfly larvae can be used to determine the quality of water in various streams, ponds, lakes, and more. The insects prefer to live in clean waters and well-oxygenated waters.
If the water is polluted, the larvae won’t be able to survive. A good dobsonfly population in water is an indicator that the water is clean.

Why was a Dobsonfly in my house?

Dobsonflies usually do not enter homes, but if you find one loitering inside your house, it must have been lured in by lights.
These insects are nocturnal and get instantly attracted to a light source in the dark. As soon as they spot a source, they start flying toward it.

What does a Dobsonfly eat?

Adult dobsonflies do not eat. They prefer to survive using the fat storage built during the larval stage. The immature dobsonflies, on the other hand, are great hunters.
They live in fast-flowing water and are excellent at hunting small aquatic insects and fishes. They, too, have sharp pincers-like jaws to clamp the prey and tear to tear it down.

How painful is a dobsonfly bite?

Male dobsonflies are harmless. Despite having enormous mandibles, they can’t generate strong enough biting force to cause pain.
Female dobsonflies have shorter mandibles but can produce enough biting force to break past the human skin and cause bleeding.
The bites are painful, but they don’t cause any long-term fatal effects.
Lastly, the larvae, ie, hellgrammites, can bite and yes, their bites are painful as well piercing to the human skin.

Where do dobsonflies lay their eggs?

They always lay eggs near water bodies. Female dobsonflies prefer to lay eggs on various structures or objects flowing above the water surface.
Sometimes if they don’t find a nearby floating object, they switch to the rock near different clean water bodies like streams.

Wrap Up

Dobsonflies may look like tiny demons, but they are a classic example of why appearances can be deceptive.

The males in particular, are entirely harmless. The female can have the capacity to deliver painful bites, but these bites won’t cause any fatal injuries or illness.

Adding to that, these aquatic insects barely invade homes and will cause no damage to household items and crops.

In fact, they are great for determining the water of various streams and lakes.

Use the information given in the article to identify which dobsonflies can bite and try to be careful around them. Thank you for taking the time to read the piece.

Reader Emails

Female dobsonflies can leave a major pinch on your skin, and many of our readers have experienced it over the years.

Read through some of the emails, watch the pics, and also learn about some of these experiences that we have learnt from the precious letters from our audience.

Letter 1 – First Male Dobsonfly posting of the season

 

Subject:  What the hell?
Geographic location of the bug:  Connecticut
Date: 06/25/2021
Time: 07:41 AM EDT
Your letter to the bugman :  Found this in our yard, near our woods.
How you want your letter signed:  Dogmom

Male Dobsonfly

Dear Dogmom,
Because of their large size and frightening appearance, Dobsonflies are one of our most common summer identification requests.  Despite his scimitar-like mandibles, this male Dobsonfly is perfectly harmless.  The much smaller mandibles on the female Dobsonfly are more functional and she can produce a painful pinch that might even draw blood.

You rock!!!
Thanks so much!
Ellen

You are most welcome Ellen, and thanks for acknowledging that we rock.

Letter 2 – Male Dobsonfly Corpse found in Maryland

 

Subject:  What’s this bug
Geographic location of the bug:  Maryland back yard Harford co
Date: 10/04/2021
Time: 08:15 AM EDT
Your letter to the bugman:  Found this dead bug in the yard never seen one before looks like it came from nars
How you want your letter signed:  G8R8RALL

Dead Male Dobsonfly

Dear G8R8RALL,
Your image of a male Dobsonfly corpse is quite impressive, but living male Dobsonflies are even more impressive.  Despite their fierce appearance, they are perfectly harmless, though the female Dobsonfly can bite (no venom) with her considerably smaller mandibles.  The larvae of Dobsonflies are known as Hellgrammites, and they might also bite.  They are considered prize bait by fishermen.

Thank you so much are They prevalent in Maryland literally this is the first one I’ve ever seen definitely never seen a live one how do they where do they hang out and how can you find them and thank you very much again

Hello again G8R8RALL,
Our original response contained links to additional postings on our site that should answer your questions.

Letter 3 – Dobsonfly from El Salvador

 

Strange and fierce bug
We found this on our window sill the other day here in San Salvador. Can you help me identify it? I’ve never seen anything like it.
Thanks,
Scotty

Hi Scotty,
You have an impressive specimen of a male Dobsonfly. I don’t know the exact species as I am only familiar with the species found in the continental U.S. We have gotten reports of male Dobsonflies that reach four inches in length. The males have the scary looking pincher jaws, but the smaller mandibles on the female are more capable of delivering a bite.

Thanks for the information. We do run across all sorts of strange stuff here that we can’t identify. Since we live up in a coffee plantation both my wife and I have been bitten by scorpions. Talk about a pop. 🙂 The Dobsonfly that we had was the length of a key. I’ll forward you another photo that shows his size. Again, thanks for the help.
Scotty

Letter 4 – Dobsonfly from India

 

A huge insect from North-East India
Mon, Apr 6, 2009 at 10:08 PM
Hi! This 14 cm long creature was calmly resting at the verandah of our hotel in Shillong, Meghalaya state (North-East India). Apparently he came attracted by very bright lights at night. He stayed at the same spot overnight, lazily responding to our attention with very slow motions of his head. In the morning, we took a piece of paper and managed to make him move and step on it, so that we could put him under a tree in the pine-tree forest which’s around. Half an hour later he was still there, but looked more jovial and was climbing over some grass.
Tatiana
Shillong, Meghalaya state; altitude: 1800 m.

Dobsonfly
Dobsonfly

Hi Tatiana,
Wow!!!! That is an impressive Dobsonfly. Beginning in May and continuing for a few months, We get reports of smaller Dobsonflies from North America. We have also had Central and South American specimens submitted to our site, but to the best of our recollection, this is the only Asian submission. Dobsonflies are impressive insects. Your specimen is a male, as evidenced by his greatly developed mandibles. The female Dobsonfly, though her mandibles are not as impressive, is a more adept biter, and she will bite if threatened, but all that will result is a pinching sensation. The insect is quite harmless. The aquatic larval stage is known as a Hellgrammite.  According to the New World Encyclodedia online, there are numerous species in India, and we cannot provide you with an exact species name.

Dobsonfly
Dobsonfly

Letter 5 – Dobsonfly from Ecuador

 

Large winged moth like thing with big pincery bits
Jul 11, 2009
Large winged moth like thing with big pincery bits
This is Arnold, who is larger than the palm of my hand and turned up every night at about 8pm when it was dark and the light was on, and seemed to really like landing on me. The pincery bits don’t appear to be mandibles, and are quite hard to the touch. Arnold brought his wife along one night, and she lacked the pincers. I have never seen anything like this, and would love to know what you think!
Leigh McIvor
Cloud Forest, 2000m.a.s North Western Ecuador

Male Dobsonfly Fly from Ecuador
Male Dobsonfly Fly from Ecuador

Hi Leigh,
Arnold is a male Dobsonfly.  Though we are uncertain of the exact species in Ecuador, it seems that Dobsonflies from around the world are quite easily identified.  Your photo showing the spread wings is quite impressive.

Letter 6 – Dobsonfly from Costa Rica

 

What the heck is this thing??
January 20, 2010
Hello a friend of mine who lives in Costa Rica took this photo while seeing a patient. He said it kept tapping the window cause it was trying to get in. He also said he could sense evil from it…
Alex Anico
Costa Rica

Dobsonfly

Hi Alex,
Despite looking diabolical, this male Dobsonfly is perfectly harmless.  The female with her smaller mandibles, on the other hand, might deliver a painful pinch if carelessly handled.

Letter 7 – Dobsonfly from Japan

 

Subject:  Biting Dragonfly?
Geographic location of the bug:  Fussa, Japan
Date: 07/14/2018
Time: 02:29 AM EDT
Your letter to the bugman:  I saw this big insect at church today. A Japanese man told me they call it a dragonfly and that it bites.
How you want your letter signed:  Ms. Beth

Dobsonfly: Protohermes grandis

Dear Ms. Beth,
This is not a Dragonfly.  It is a Dobsonfly or Fishfly in the family Corydalidae, and females have formidable mandibles that might even draw blood if they bite, but they are not considered dangerous.  We believe we identified the species as
 Protohermes grandis on The Royal Society Publishing site.  We verified that on Minden Pictures.

Reader Emails

24584

Letter 1 – Drawing of a Hellgrammite

 

Unusual Specimen April 29, 2010 Unfortunately I don’t have an actual picture. Me and my buddy were fishing up in the san luis mountains in colorado and were looking for bait under old downed logs. We hooked what we thought was a grub worm at first. After taking a closer look, the bug appeared to have sharp clamps that could latch onto things and refuse to let go, Ive looked everywhere to find what kind of bug this may be. nothing. Maybe someone here may have some insight on what this could be. Sorry i dont have a picture 🙁 im going back up there this summer and hopefully i can find another one. Jonathan Gage San Luis Mountains in Colorado
Hellgrammite
Hi Jonathan, Your excellent drawing and description leaves little doubt in our mind that you had an encounter with a Hellgrammite, the larva of a Dobsonfly, and one of the best live baits according to anglers who write to us.

Letter 2 – Cat and Dog curious about Hellgrammite

 

what IS this nasty thing!? May 6, 2010 i live in northeastern ontario, just south of algonquin park (minden, ontario). the other day, my cat brought one of these nasty uglies into the house. it was literally lunging at the cat and the dog. i scooped it into a cup and pitched it out into the yard. the next morning, a blue jay was attacking one in the front yard and having a hell of a time of it. that night, the dog brought one in. i’ve been told these are not native to my region – what gives?! threenorns minden, ontario
Hellgrammite fascinates dog and cat
Hi there threenorns, This picture is quite intriguing.  Your dog and cat are transfixed by a Hellgrammite, the larva of a Dobsonfly, and it is a local species for you.  Fishermen love to use Hellgrammites as live bait.  We are setting your letter and photo to post next Wednesday, the last day of our trip back to Ohio to visit with mom.

Letter 3 – Hellgrammite

 

Black, pinchers on head, looks like 20 legs,attracted to lantern May 24, 2010 I found this bug along a river in western Pennsylvania Glenn Connellsville, Pennsylvania
Hellgrammite
Dear Glenn, You have such a descriptive title.  This is a Hellgrammite, the larval form of the Dobsonfly.

Letter 4 – Hellgrammite

 

Unusual “Centipede”? May 30, 2010 I went camping with a troupe of friends and relatives. My friend and I went out for a walk while the others stayed behind at the cabin – on our return they beckoned us over to a cup where they produced this monstrosity. Apparently, while we were gone, this bug fell from above and into my mother’s hair. It is a miracle they rescued it alive – they are the type to kill nearly everything they come across – but I think perhaps it was its uniqueness that saved its life. I’ve never seen anything like it and I’ve lived in the same house all of my life. There are a few theories going around, the main contender is that it may be some unidentified form of centipede. I had a glance through your centipede pages but it did not look like a single one of them. It also seems to have a mouth meant to suck sap or juices from roots, so the second theory is that it may be a larvae stage for something… My friend who I went on a walk with had the chance to touch it after she released it. She said that it quickly burrowed in the ground (supporting the ‘it drinks from roots…maybe..’ theory), and that when she touched it it felt like snake skin. I did not get the chance to do so. I apologize about the quality of the pictures I’m sending, the cup which they’d trapped the bug in was reflective and the room was dark – so I needed to use flash, unfortunately. I included a coin (a penny) for comparative size in the third picture, though it may be a bit hard to see from over exposure. Please let us know what it is! Kaden James South-Eastern Connecticut, USA.
Hellgrammite
Hi Kaden, Your mystery creature is a Hellgrammite, the larval form of the Dobsonfly.  Hellgrammites are aquatic, but they can survive on land, and they are predatory.

Letter 5 – Hellgrammite

 

What North American swamp crawler is this? June 3, 2010 I found this scary little bugger crawling across the C&O Canal about 5 miles outside of D.C. It was probably 3 inches long, and all brownish black. It had a dull sheen to its exoskeleton. Although it appears to have many legs like a centipede, it only used the six longer legs (three on each side) on its thorax for movement. The other legs on the abdomen weren’t moving, and seemed to be spikes. The abdomen takes up half of the total body length, and seems very flexible in movement like a human tongue. On its head, were two proportionally large pinsirs. When provoked (by my shoe) it reared back a little into the air, and opened these pinsirs wide as a warning. When under attack, the abdomen was able to curl and launch the creature perfectly backwards away from my foot, in a fluent movement. It could repeatedly do this like a crawfish jets backwards with its tail. When crawling forwards normally, the bug did not have an “S’ movement, but was about to crawl perfectly straight, barely using its abdomen. It had no antennas also. What kind of bug is this? P.S. I have a video of the bug writhing backwards, but your site won’t allow me to upload it. Would you like it? Joey C. Washington D.C. on the C&O Canal
Hellgrammite
Hi Joey, You had an encounter with a Hellgrammite, the larva of a Dobsonfly.

Letter 6 – Hellgrammite

 

Ant Lion? June 4, 2010 Hi! We found this monster crawling from the edge of the Muskegon River in Michigan toward the wood line. I thought it was an ant lion, but I haven’t seen any pictures of ant lions that look like this thing. I have video, also, if you’d like to see the creepy way the thing ambulated… What the heck is it? It was HUGE! Eric Kincaid Newaygo, MI
Hellgrammite
Hi Eric, In the past week, we have been getting numerous photos of Hellgrammites like the one in your photo.  We are also beginning to get images of adult Dobsonflies, the winged form of this aquatic larva.  The male Dobsonfly possesses enormous saber-like mandibles, and if you think this Hellgrammite is frightening, wait until you see its daddy.  Hellgrammites and Dobsonflies are both harmless, though the mandibles of the larva and those of the female can deliver a painful pinch, and possibly even draw blood.  The foot is a nice use of scale.
Hellgrammite

Letter 7 – Hellgrammite

 

Centipede???? June 6, 2010 My daughter ran across this little guy and scared her to death. I told her it was a centipede. But after looking online I am starting to doubt my self. This guy lacks the large antenna all the other centipedes have. And his rear end is a single appendage, compared to most other centipedes with a split tail. Any help IDing this guy would be very appreciated. Sorry about quality took pic with camera phone. Pic taken on Apr 30 2010 Thanks Aaron West Virginia
Hellgrammite
Hi Aaron, The Hellgrammites are crawling out of the woodwork this year!!!  Actually, Hellgrammites do not live in woodwork, but the point we are making is that there is an unusually plentiful number of identification requests coming our way for both the larval form and the adult Dobsonfly.  We believe the Hellgrammite was the inspiration for the creature in the classic horror film, The Tingler starring Vincent Price.

Letter 8 – Hellgrammite

 

Strange bug found off shore of creek. June 6, 2010 Hi, I found a strange bug today (6/6/10) while fishing and I was wondering if you could help me idetify it. I turned over a rock that was about ten to fifteen feet from a creek and I saw this thing curled up in a little hole in the mud. It was on land not in the water. It almost looked like it had hatched there and grew because there was no real entry or exit from its location. There was a pretty tight seal because of the flatness of the rock. Also it wasnt moving almost like it was hibernating there. I scooped it up in a cup and it kicked around a little but all in all not real movement. It has big legs in the front but a long body so Im not sure how it would move. It has some pretty serious pincers on its mouth. It bit pretty hard onto a stick. I have no idea what t his thing is and neither does anyone I show it too. Any info would help. Thanks Matthew R. Boyer Southeastern Pennsylvania
Hellgrammite
Hi Matthew, Hellgrammite identification requests like yours have been pouring into our offices from around the country, as are images of the adult Dobsonflies the Hellgrammites will eventually metamorphose into.

Letter 9 – Hellgrammite

 

Centipede Perhaps? June 14, 2010 I am eight years old and I was at a lake and being the bug lover that I am I brought this home. I found this guy under a rock in the water at our town lake. Can anyone tell me what the heck it is? He is really neat. You can see him breathing and everything. He is quite amazing. He has little bushes between his legs that flare out when he breathes. I have tried to do some research on my bug but cant seem to find out much. One article I found was a bug dating back 2,000 years. So I am really interested in finding out what he is. What to grow up to be a bug man! Western Colorado
Hellgrammite
Dear future bug man, This appears to be a Hellgrammite, the larval form of the fearsome Dobsonfly.  Adults are harmless, though females may provide a painful pinch, like the larval Hellgrammites.  Hellgrammites are a favored live bait for many freshwater anglers. Update:  September 2, 2010 Based on research for a new letter, we should indicate that the Hellgrammite in this photo is probably the Western Dobsonfly, Corydalus texana, a species that ranges west of the Rocky Mountains based on information posted to BugGuide.

Letter 10 – Possibly an encounter with a Hellgrammite

 

Centipede-like bug with pincers? Location:  Utah September 2, 2010 1:26 am I have been searching long and hard for a site where I could ask about a bug I found, so here goes! Unfortunately I don’t have a picture (but I drew it? haha) of it since I was too frightened to catch it and I didnt have my camera with me at the time. It was also very dark when I found it and I was in a river… I was swimming around, looking for tadpoles and frogs. And then much to my horror I shined my flashlight upon something that was definitely neither of those. I can’t remember exactly what it looked like but it had a very long centipede-like body with a lot of legs like one. I think it was white and black (but it was nighttime, and I wasn’t really paying attention to its color for obvious reasons) and it was coming out from under a rock. So it obviously lives in the water. And it had very sharp needle-like pincers that curved in and looked like it could chop your finger off if it got close enough. I’ve looked everywhere for one. All over the internet, and I can’t seem to find anything that looks even remotely close to it. I really wish I had taken a picture of it! Does something like this exist? Or is it some freak science-experiment gone wrong? I’m sorry, I wish I had a better explanation of what it looked like (and a better drawing!). The next day I went back hoping to catch it but I didn’t see it anywhere. Of course it only shows up when it isn’t wanted. Signature:  Maddie
Possibly a Hellgrammite
Hi Maddie, We were quite certain based on your drawing and your letter that you had an encounter with a Hellgrammite, the aquatic larva of a Dobsonfly, but we began to question that theory when we realized your sighting was in Utah.  The commonly encountered Eastern Dobsonfly does not range to Utah, but there are three other species that occur in western states.  According to BugGuide: “The only eastern species is Eastern Dobsonfly, Corydalus cornutus. Three other species apparently have very limited distribution in North America: Corydalus luteus – South Texas Corydalus texana – SW US west of the Rocky Mountains Corydalus bidenticulatus – Arizona Genus is restricted to the New World–other species in Central and South America.” We were unable to locate an image of a Western Dobsonfly, Corydalus texana, but a web search did lead us to a trout fishing page with a photograph of a Dobsonfly and a nice description.  The God of Insects website also has some information.  We are posting your letter with an image of the Hellgrammite of an Eastern Dobsonfly as we imagine the western counterpart must look very similar.
Hellgrammite
Interestingly, we did notice that one of our earlier postings is from Colorado, which would indicate there is a strong possibility that image is of Corydalus texana.

Letter 11 – Hellgrammite or Helljamite???

 

Scary River Centipede Location: Cahaba River, AL December 13, 2010 12:45 am Dear Bugman, I looked through many pictures, but because I am scared of things with so many legs I felt sick. All I can do is ask, what kind of bug is this? I found it while swimming in the Cahaba River by my Grandmothers house near Birmingham, Alabama in July. It was found inside the river and swam kind of fast…well, it squirmed through the water fast. The creature is four or five inches long. I was wondering if it might be what bit my foot while I was swimming the week before? The picture is what I got when I scooped it up with my cousin’s swim mask. Signature: Grossed out Nursing Student
Hellgrammite
Dear Grossed out Nursing Student, Though it looks very much like a Centipede, this Hellgrammite is actually an insect larva.  Imagine the winged adult male with saber-like mandibles an inch long, and you will have some idea of what the adult Dobsonfly looks like.  Hellgrammites can bite, and the bite might even draw blood, but the fierce looking creature is actually harmless.  Fishermen relish them as bait.  When he was researching his book, Daniel tried unsuccessfully to uncover the origin of the word Hellgrammite, but even without an origin, the name seems appropriate for this fascinating insect. Update:  June 20. 2021 We love the comment we just approved:  “They are called Helljamites…grandpa told us kids if one bites you you may live and helljamite not !!!”  

Letter 12 – Hellgrammite

 

Nymph Location: Cochise County, Arizona February 14, 2011 8:15 pm Dear Bugdude, A friend took these photos and gave me permission to send them in. She photographed the nymph in a stream in the Chiricahua Mountains, Cochise County, Arizona, it was about 2 – 2 1/2 inches in lenght. I’ve searched and searched the internet and cannot seem to locate a photo to identify this nymph. Signature: Huh?
Hellgrammite
Dear Huh?, This appears to be a Hellgrammite, the larva of a Dobsonfly or Fishfly in the family Corydalidae which you may compare to this image on BugGuide.  Most of our images of Hellgrammites are from the Eastern Dobsonfly, Corydalus cornutus, and BugGuide does not report them any further west than Texas, however, BugGuide does report a genus member being sighted in Arizona, and the information page on the genus on BugGuide does list four species, with this information:  “Corydalus texana – SW US west of the Rocky Mountains” and “Corydalus bidenticulatus – Arizona” indicating that this individual may be either of those species.

Letter 13 – Hellgrammite

 

Scaley bug with pinchers on head? Location: Hector, Arkansas May 2, 2011 2:05 am We ran across this bug at a Girl Scout campout. It cause quite the commotion as it was in one of the bath houses and most of the little girls wanted to squish it. (No, we did not allow that!) Other girls were facinated by this creepy crawly. All of us adults just want to know what is that big? Thanks for any help you can give. Signature: ~Jen from Arkansas
Hellgrammite
Hi Jen, This formidable larva is known as a Hellgrammite, and it will eventually metamorphose into the fierce looking, bug harmless Dobsonfly, a flying giant with substantial mandibles.  You can find countless images of both Dobsonflies and Hellgramites on our website including this one.

Letter 14 – Hellgrammite

 

what type of water bug is this? Location: Mariposa, California (Sierra Nevada) May 12, 2011 12:03 am Found this in our creek and called it a water centipede because it resembles a regular centipede so much. It has pretty big mandibles and tried to give a bite when picked out of the water. Rarely ever see these around here. What is it? Signature: Aiden
Hellgrammite
Hi Aiden, You have encountered the predatory larva of one of the members of the family Corydalidae, the Dobsonflies and Fishflies.  The larva of the Eastern Dobsonfly is known as a Hellgrammite, and though this is not the Eastern Dobsonfly, we feel the common name Hellgrammite should still apply.  We will try to determine the species.

Letter 15 – Hellgrammite

 

6 legs, large jaws, spikes over a long body Location: Riverdale NJ (northest US) May 19, 2011 7:36 am Dear Bug, I found this odd looking bug alog some railroad ties out back. He was very agressive (opening jaws) as we managed to catch him. I’ve never seen anything like this and was hoping you can identify his species and if we need be concerned of our son and his friends playing out back. Thanks, Bugfinder Signature: Paul Thank you!  Forgot to mention he/she is exactly 3 inches log from tip of jaw to end of tail!
Hellgrammite
Hi Paul, This is a Hellgrammite, the larval form of the Dobsonfly.  Despite all of our efforts, we have been unable to trace the origin of the name Hellgrammite, which nonetheless seems a very appropriate name for this unforgettable insect.

Letter 16 – Hellgrammite

 

puzzled in Pa? Location: western Pa May 22, 2011 10:00 pm My boyfriend and I were out walking along the shore of the Ligonier Creek in western Pa, we spotted a nice location to sit and talk on a couple of larger rocks. My boyfriend picked up a smaller rock to skip across the creek when we came accross this insect. We both love being outdoors but we never saw a bug like this before. So we picked it up put it in a container and brought it home with us for further analysis. WE ARE STUMPED!! Can you help? We would like to release it back into the wild tomorrow. Thanks alot! Signature: puzzled in Pa
Hellgrammite
Dear puzzled in Pa, This is a Hellgrammite, the larval form of a Dobsonfly.  If you think this larva is impressive, you should check out some images of adult male Dobsonflies in our archive.

Letter 17 – Hellgrammite

 

found this while camping Location: North eastern PA in woods May 29, 2011 5:36 pm Hi, we found this bug at Promised Land State Park in PA. It was a moist morning and our neighbor found it on the cabin porch. He took a stick and was going to move it when it crawled on the stick but the darn thing started to fight with the stick!! It was about 3-4” long and later when I tried to move it, it backed straight back like an inch worm goes forward. Can you identify this critter?? thank you very much Signature: Sue Sacks
Hellgrammite
Dear Sue, We have no shortage of images and information on Hellgrammites on our website, and we hope you will do additional research using our excellent search engine since that will provide you with some specifics on this fascinating larval form of the Dobsonfly.  We love your observation regarding the Hellgrammite defending itself against the stick.

Letter 18 – Hellgrammite

 

Unfortunate circumstances in need of creature identification June 5, 2011 8:49 pm Dear Bugman, I found this creature alongside the winooski river in winooski, Vermont a few days ago. I found him out of water but moving very little. I attempted to instigate a fight between this behemoth we dearly call “Petunia” and a wolf spider. To my dismay there was no battle. Petunia retreated to a small pool of water and became more active. Perplexed by this creature I have adopted Petunia and am attempting to find out what to feed her. It may appear that she eats ants as she destroyed one when introduced to her pool. However due to her gills, which are on both sides of her below her legs, I am unsure if she is even an insect.  Bugman I hope you can solve this mystery as Petunia must be getting hungry by now. After writing you this letter I have realized I cannot attach images to your website from my iPhone and unfortunately it as all the internet access we have at my residence. If you respond I will send you the picture as an attachment with due haste. Signature: Jack D
Hellgrammite
Dear Jack, This is a Hellgrammite, the predatory larva of a Dobsonfly.

Letter 19 – Hellgrammite

 

Tattooed Bug? Location: South Texas Hill country July 3, 2011 2:26 pm My husband found this creature on the underside of a rock in the Guadalupe River this summer. We had never seen anything quite like it and our kids think it looks like it has been tattooed. It is about 3 inches long. Signature: The Walling Family
Hellgrammite
Dear Walling Family, This incredible creature is called a Hellgrammite, and it is the larval form of the Dobsonfly.

Reader Emails

24584

Letter 1 – Drawing of a Hellgrammite

 

Unusual Specimen April 29, 2010 Unfortunately I don’t have an actual picture. Me and my buddy were fishing up in the san luis mountains in colorado and were looking for bait under old downed logs. We hooked what we thought was a grub worm at first. After taking a closer look, the bug appeared to have sharp clamps that could latch onto things and refuse to let go, Ive looked everywhere to find what kind of bug this may be. nothing. Maybe someone here may have some insight on what this could be. Sorry i dont have a picture 🙁 im going back up there this summer and hopefully i can find another one. Jonathan Gage San Luis Mountains in Colorado
Hellgrammite
Hi Jonathan, Your excellent drawing and description leaves little doubt in our mind that you had an encounter with a Hellgrammite, the larva of a Dobsonfly, and one of the best live baits according to anglers who write to us.

Letter 2 – Cat and Dog curious about Hellgrammite

 

what IS this nasty thing!? May 6, 2010 i live in northeastern ontario, just south of algonquin park (minden, ontario). the other day, my cat brought one of these nasty uglies into the house. it was literally lunging at the cat and the dog. i scooped it into a cup and pitched it out into the yard. the next morning, a blue jay was attacking one in the front yard and having a hell of a time of it. that night, the dog brought one in. i’ve been told these are not native to my region – what gives?! threenorns minden, ontario
Hellgrammite fascinates dog and cat
Hi there threenorns, This picture is quite intriguing.  Your dog and cat are transfixed by a Hellgrammite, the larva of a Dobsonfly, and it is a local species for you.  Fishermen love to use Hellgrammites as live bait.  We are setting your letter and photo to post next Wednesday, the last day of our trip back to Ohio to visit with mom.

Letter 3 – Hellgrammite

 

Black, pinchers on head, looks like 20 legs,attracted to lantern May 24, 2010 I found this bug along a river in western Pennsylvania Glenn Connellsville, Pennsylvania
Hellgrammite
Dear Glenn, You have such a descriptive title.  This is a Hellgrammite, the larval form of the Dobsonfly.

Letter 4 – Hellgrammite

 

Unusual “Centipede”? May 30, 2010 I went camping with a troupe of friends and relatives. My friend and I went out for a walk while the others stayed behind at the cabin – on our return they beckoned us over to a cup where they produced this monstrosity. Apparently, while we were gone, this bug fell from above and into my mother’s hair. It is a miracle they rescued it alive – they are the type to kill nearly everything they come across – but I think perhaps it was its uniqueness that saved its life. I’ve never seen anything like it and I’ve lived in the same house all of my life. There are a few theories going around, the main contender is that it may be some unidentified form of centipede. I had a glance through your centipede pages but it did not look like a single one of them. It also seems to have a mouth meant to suck sap or juices from roots, so the second theory is that it may be a larvae stage for something… My friend who I went on a walk with had the chance to touch it after she released it. She said that it quickly burrowed in the ground (supporting the ‘it drinks from roots…maybe..’ theory), and that when she touched it it felt like snake skin. I did not get the chance to do so. I apologize about the quality of the pictures I’m sending, the cup which they’d trapped the bug in was reflective and the room was dark – so I needed to use flash, unfortunately. I included a coin (a penny) for comparative size in the third picture, though it may be a bit hard to see from over exposure. Please let us know what it is! Kaden James South-Eastern Connecticut, USA.
Hellgrammite
Hi Kaden, Your mystery creature is a Hellgrammite, the larval form of the Dobsonfly.  Hellgrammites are aquatic, but they can survive on land, and they are predatory.

Letter 5 – Hellgrammite

 

What North American swamp crawler is this? June 3, 2010 I found this scary little bugger crawling across the C&O Canal about 5 miles outside of D.C. It was probably 3 inches long, and all brownish black. It had a dull sheen to its exoskeleton. Although it appears to have many legs like a centipede, it only used the six longer legs (three on each side) on its thorax for movement. The other legs on the abdomen weren’t moving, and seemed to be spikes. The abdomen takes up half of the total body length, and seems very flexible in movement like a human tongue. On its head, were two proportionally large pinsirs. When provoked (by my shoe) it reared back a little into the air, and opened these pinsirs wide as a warning. When under attack, the abdomen was able to curl and launch the creature perfectly backwards away from my foot, in a fluent movement. It could repeatedly do this like a crawfish jets backwards with its tail. When crawling forwards normally, the bug did not have an “S’ movement, but was about to crawl perfectly straight, barely using its abdomen. It had no antennas also. What kind of bug is this? P.S. I have a video of the bug writhing backwards, but your site won’t allow me to upload it. Would you like it? Joey C. Washington D.C. on the C&O Canal
Hellgrammite
Hi Joey, You had an encounter with a Hellgrammite, the larva of a Dobsonfly.

Letter 6 – Hellgrammite

 

Ant Lion? June 4, 2010 Hi! We found this monster crawling from the edge of the Muskegon River in Michigan toward the wood line. I thought it was an ant lion, but I haven’t seen any pictures of ant lions that look like this thing. I have video, also, if you’d like to see the creepy way the thing ambulated… What the heck is it? It was HUGE! Eric Kincaid Newaygo, MI
Hellgrammite
Hi Eric, In the past week, we have been getting numerous photos of Hellgrammites like the one in your photo.  We are also beginning to get images of adult Dobsonflies, the winged form of this aquatic larva.  The male Dobsonfly possesses enormous saber-like mandibles, and if you think this Hellgrammite is frightening, wait until you see its daddy.  Hellgrammites and Dobsonflies are both harmless, though the mandibles of the larva and those of the female can deliver a painful pinch, and possibly even draw blood.  The foot is a nice use of scale.
Hellgrammite

Letter 7 – Hellgrammite

 

Centipede???? June 6, 2010 My daughter ran across this little guy and scared her to death. I told her it was a centipede. But after looking online I am starting to doubt my self. This guy lacks the large antenna all the other centipedes have. And his rear end is a single appendage, compared to most other centipedes with a split tail. Any help IDing this guy would be very appreciated. Sorry about quality took pic with camera phone. Pic taken on Apr 30 2010 Thanks Aaron West Virginia
Hellgrammite
Hi Aaron, The Hellgrammites are crawling out of the woodwork this year!!!  Actually, Hellgrammites do not live in woodwork, but the point we are making is that there is an unusually plentiful number of identification requests coming our way for both the larval form and the adult Dobsonfly.  We believe the Hellgrammite was the inspiration for the creature in the classic horror film, The Tingler starring Vincent Price.

Letter 8 – Hellgrammite

 

Strange bug found off shore of creek. June 6, 2010 Hi, I found a strange bug today (6/6/10) while fishing and I was wondering if you could help me idetify it. I turned over a rock that was about ten to fifteen feet from a creek and I saw this thing curled up in a little hole in the mud. It was on land not in the water. It almost looked like it had hatched there and grew because there was no real entry or exit from its location. There was a pretty tight seal because of the flatness of the rock. Also it wasnt moving almost like it was hibernating there. I scooped it up in a cup and it kicked around a little but all in all not real movement. It has big legs in the front but a long body so Im not sure how it would move. It has some pretty serious pincers on its mouth. It bit pretty hard onto a stick. I have no idea what t his thing is and neither does anyone I show it too. Any info would help. Thanks Matthew R. Boyer Southeastern Pennsylvania
Hellgrammite
Hi Matthew, Hellgrammite identification requests like yours have been pouring into our offices from around the country, as are images of the adult Dobsonflies the Hellgrammites will eventually metamorphose into.

Letter 9 – Hellgrammite

 

Centipede Perhaps? June 14, 2010 I am eight years old and I was at a lake and being the bug lover that I am I brought this home. I found this guy under a rock in the water at our town lake. Can anyone tell me what the heck it is? He is really neat. You can see him breathing and everything. He is quite amazing. He has little bushes between his legs that flare out when he breathes. I have tried to do some research on my bug but cant seem to find out much. One article I found was a bug dating back 2,000 years. So I am really interested in finding out what he is. What to grow up to be a bug man! Western Colorado
Hellgrammite
Dear future bug man, This appears to be a Hellgrammite, the larval form of the fearsome Dobsonfly.  Adults are harmless, though females may provide a painful pinch, like the larval Hellgrammites.  Hellgrammites are a favored live bait for many freshwater anglers. Update:  September 2, 2010 Based on research for a new letter, we should indicate that the Hellgrammite in this photo is probably the Western Dobsonfly, Corydalus texana, a species that ranges west of the Rocky Mountains based on information posted to BugGuide.

Letter 10 – Possibly an encounter with a Hellgrammite

 

Centipede-like bug with pincers? Location:  Utah September 2, 2010 1:26 am I have been searching long and hard for a site where I could ask about a bug I found, so here goes! Unfortunately I don’t have a picture (but I drew it? haha) of it since I was too frightened to catch it and I didnt have my camera with me at the time. It was also very dark when I found it and I was in a river… I was swimming around, looking for tadpoles and frogs. And then much to my horror I shined my flashlight upon something that was definitely neither of those. I can’t remember exactly what it looked like but it had a very long centipede-like body with a lot of legs like one. I think it was white and black (but it was nighttime, and I wasn’t really paying attention to its color for obvious reasons) and it was coming out from under a rock. So it obviously lives in the water. And it had very sharp needle-like pincers that curved in and looked like it could chop your finger off if it got close enough. I’ve looked everywhere for one. All over the internet, and I can’t seem to find anything that looks even remotely close to it. I really wish I had taken a picture of it! Does something like this exist? Or is it some freak science-experiment gone wrong? I’m sorry, I wish I had a better explanation of what it looked like (and a better drawing!). The next day I went back hoping to catch it but I didn’t see it anywhere. Of course it only shows up when it isn’t wanted. Signature:  Maddie
Possibly a Hellgrammite
Hi Maddie, We were quite certain based on your drawing and your letter that you had an encounter with a Hellgrammite, the aquatic larva of a Dobsonfly, but we began to question that theory when we realized your sighting was in Utah.  The commonly encountered Eastern Dobsonfly does not range to Utah, but there are three other species that occur in western states.  According to BugGuide: “The only eastern species is Eastern Dobsonfly, Corydalus cornutus. Three other species apparently have very limited distribution in North America: Corydalus luteus – South Texas Corydalus texana – SW US west of the Rocky Mountains Corydalus bidenticulatus – Arizona Genus is restricted to the New World–other species in Central and South America.” We were unable to locate an image of a Western Dobsonfly, Corydalus texana, but a web search did lead us to a trout fishing page with a photograph of a Dobsonfly and a nice description.  The God of Insects website also has some information.  We are posting your letter with an image of the Hellgrammite of an Eastern Dobsonfly as we imagine the western counterpart must look very similar.
Hellgrammite
Interestingly, we did notice that one of our earlier postings is from Colorado, which would indicate there is a strong possibility that image is of Corydalus texana.

Letter 11 – Hellgrammite or Helljamite???

 

Scary River Centipede Location: Cahaba River, AL December 13, 2010 12:45 am Dear Bugman, I looked through many pictures, but because I am scared of things with so many legs I felt sick. All I can do is ask, what kind of bug is this? I found it while swimming in the Cahaba River by my Grandmothers house near Birmingham, Alabama in July. It was found inside the river and swam kind of fast…well, it squirmed through the water fast. The creature is four or five inches long. I was wondering if it might be what bit my foot while I was swimming the week before? The picture is what I got when I scooped it up with my cousin’s swim mask. Signature: Grossed out Nursing Student
Hellgrammite
Dear Grossed out Nursing Student, Though it looks very much like a Centipede, this Hellgrammite is actually an insect larva.  Imagine the winged adult male with saber-like mandibles an inch long, and you will have some idea of what the adult Dobsonfly looks like.  Hellgrammites can bite, and the bite might even draw blood, but the fierce looking creature is actually harmless.  Fishermen relish them as bait.  When he was researching his book, Daniel tried unsuccessfully to uncover the origin of the word Hellgrammite, but even without an origin, the name seems appropriate for this fascinating insect. Update:  June 20. 2021 We love the comment we just approved:  “They are called Helljamites…grandpa told us kids if one bites you you may live and helljamite not !!!”  

Letter 12 – Hellgrammite

 

Nymph Location: Cochise County, Arizona February 14, 2011 8:15 pm Dear Bugdude, A friend took these photos and gave me permission to send them in. She photographed the nymph in a stream in the Chiricahua Mountains, Cochise County, Arizona, it was about 2 – 2 1/2 inches in lenght. I’ve searched and searched the internet and cannot seem to locate a photo to identify this nymph. Signature: Huh?
Hellgrammite
Dear Huh?, This appears to be a Hellgrammite, the larva of a Dobsonfly or Fishfly in the family Corydalidae which you may compare to this image on BugGuide.  Most of our images of Hellgrammites are from the Eastern Dobsonfly, Corydalus cornutus, and BugGuide does not report them any further west than Texas, however, BugGuide does report a genus member being sighted in Arizona, and the information page on the genus on BugGuide does list four species, with this information:  “Corydalus texana – SW US west of the Rocky Mountains” and “Corydalus bidenticulatus – Arizona” indicating that this individual may be either of those species.

Letter 13 – Hellgrammite

 

Scaley bug with pinchers on head? Location: Hector, Arkansas May 2, 2011 2:05 am We ran across this bug at a Girl Scout campout. It cause quite the commotion as it was in one of the bath houses and most of the little girls wanted to squish it. (No, we did not allow that!) Other girls were facinated by this creepy crawly. All of us adults just want to know what is that big? Thanks for any help you can give. Signature: ~Jen from Arkansas
Hellgrammite
Hi Jen, This formidable larva is known as a Hellgrammite, and it will eventually metamorphose into the fierce looking, bug harmless Dobsonfly, a flying giant with substantial mandibles.  You can find countless images of both Dobsonflies and Hellgramites on our website including this one.

Letter 14 – Hellgrammite

 

what type of water bug is this? Location: Mariposa, California (Sierra Nevada) May 12, 2011 12:03 am Found this in our creek and called it a water centipede because it resembles a regular centipede so much. It has pretty big mandibles and tried to give a bite when picked out of the water. Rarely ever see these around here. What is it? Signature: Aiden
Hellgrammite
Hi Aiden, You have encountered the predatory larva of one of the members of the family Corydalidae, the Dobsonflies and Fishflies.  The larva of the Eastern Dobsonfly is known as a Hellgrammite, and though this is not the Eastern Dobsonfly, we feel the common name Hellgrammite should still apply.  We will try to determine the species.

Letter 15 – Hellgrammite

 

6 legs, large jaws, spikes over a long body Location: Riverdale NJ (northest US) May 19, 2011 7:36 am Dear Bug, I found this odd looking bug alog some railroad ties out back. He was very agressive (opening jaws) as we managed to catch him. I’ve never seen anything like this and was hoping you can identify his species and if we need be concerned of our son and his friends playing out back. Thanks, Bugfinder Signature: Paul Thank you!  Forgot to mention he/she is exactly 3 inches log from tip of jaw to end of tail!
Hellgrammite
Hi Paul, This is a Hellgrammite, the larval form of the Dobsonfly.  Despite all of our efforts, we have been unable to trace the origin of the name Hellgrammite, which nonetheless seems a very appropriate name for this unforgettable insect.

Letter 16 – Hellgrammite

 

puzzled in Pa? Location: western Pa May 22, 2011 10:00 pm My boyfriend and I were out walking along the shore of the Ligonier Creek in western Pa, we spotted a nice location to sit and talk on a couple of larger rocks. My boyfriend picked up a smaller rock to skip across the creek when we came accross this insect. We both love being outdoors but we never saw a bug like this before. So we picked it up put it in a container and brought it home with us for further analysis. WE ARE STUMPED!! Can you help? We would like to release it back into the wild tomorrow. Thanks alot! Signature: puzzled in Pa
Hellgrammite
Dear puzzled in Pa, This is a Hellgrammite, the larval form of a Dobsonfly.  If you think this larva is impressive, you should check out some images of adult male Dobsonflies in our archive.

Letter 17 – Hellgrammite

 

found this while camping Location: North eastern PA in woods May 29, 2011 5:36 pm Hi, we found this bug at Promised Land State Park in PA. It was a moist morning and our neighbor found it on the cabin porch. He took a stick and was going to move it when it crawled on the stick but the darn thing started to fight with the stick!! It was about 3-4” long and later when I tried to move it, it backed straight back like an inch worm goes forward. Can you identify this critter?? thank you very much Signature: Sue Sacks
Hellgrammite
Dear Sue, We have no shortage of images and information on Hellgrammites on our website, and we hope you will do additional research using our excellent search engine since that will provide you with some specifics on this fascinating larval form of the Dobsonfly.  We love your observation regarding the Hellgrammite defending itself against the stick.

Letter 18 – Hellgrammite

 

Unfortunate circumstances in need of creature identification June 5, 2011 8:49 pm Dear Bugman, I found this creature alongside the winooski river in winooski, Vermont a few days ago. I found him out of water but moving very little. I attempted to instigate a fight between this behemoth we dearly call “Petunia” and a wolf spider. To my dismay there was no battle. Petunia retreated to a small pool of water and became more active. Perplexed by this creature I have adopted Petunia and am attempting to find out what to feed her. It may appear that she eats ants as she destroyed one when introduced to her pool. However due to her gills, which are on both sides of her below her legs, I am unsure if she is even an insect.  Bugman I hope you can solve this mystery as Petunia must be getting hungry by now. After writing you this letter I have realized I cannot attach images to your website from my iPhone and unfortunately it as all the internet access we have at my residence. If you respond I will send you the picture as an attachment with due haste. Signature: Jack D
Hellgrammite
Dear Jack, This is a Hellgrammite, the predatory larva of a Dobsonfly.

Letter 19 – Hellgrammite

 

Tattooed Bug? Location: South Texas Hill country July 3, 2011 2:26 pm My husband found this creature on the underside of a rock in the Guadalupe River this summer. We had never seen anything quite like it and our kids think it looks like it has been tattooed. It is about 3 inches long. Signature: The Walling Family
Hellgrammite
Dear Walling Family, This incredible creature is called a Hellgrammite, and it is the larval form of the Dobsonfly.

Reader Emails

24584

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Hellgrammite from Honduras

 

I belive this may be some type of anthropod but not really sure. April 20, 2010 My wife and I took a cruise and after leaving Roatan, Honduras I saw this bug crawling in the hallway outside our room. It was approximately 4 inches long and was not moving very fast. I was able to get two shots of it before the cabin steward came and squashed it. James Babcock Roatan, Honduras
Hellgrammite
Hi James, You encountered a Hellgrammite, the larval form of the winged Dobsonfly.  This is such a magnificent and unforgettable insect, we believe there must be some colorful name for it in Spanish as well.

Authors

    by
  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

    View all posts
  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

    View all posts

29 thoughts on “Are Dobsonfly Dangerous? How To Get Rid Of Dobsonflies?”

  1. Thank you so much for responding is such a timely manner on my insect query. Now that my knowledge of this type of insect is a little broader, I was shocked to see how common it was. Once again thank you.

    James B.

    Reply
  2. WOW, I HAVE FOUND BOTH THE HELLGRAMMITE AND THE MATURE DOBSONFLY THIS YEAR. I THOUGHT I HAD SEEN ABOUT EVERYTHING IN OHIO, BUT THIS BUG REALLY SHOCKED ME AT IT’S SIZE. GREAT TO HAVE FOUND SUCH A NEAT SITE WITH OTHERS SO INTERESTED IN THE LITTLE CREATURES.

    Reply
  3. We were fishing with them and one of the guys with us thought he had a bite but when he got it on land the hellgrammite had a bluegill pinched right between its eyes, he walked around showing all the other fishers and the hellgrammite wouldn’t let go.

    Reply
  4. We had one of these crawling on our tent the other night near the Colorado River, 7 miles NW of Moab, UT. Scary looking guy.

    Reply
  5. I found somthing simular in color and species here in iowa back when we had very bad flooding eccept we caught one and it had hind pincers and was very fast and aggressive it might have been a hellgrammite species.

    Reply
  6. Found one under the rocks in the water in Stxy River Alabama of Co Rd 64. It was about 21/2 or 3 inches. I have been swimming in the river most of my life. I am almost 50. First one I ever saw. Took a bit to research and find out what it was. Nice to know they indicate whether water is polluted which is what I read on another bug site. Freaky lookin bug. Nice to know they are good for fishing…just think I may have a hard time finding enough. Thanks CJ

    Reply
  7. Dear friends, I have encountered that exact same insect and had video of it. I will dig it up if you ask it was 4 years ago and I have been searching ever since. Only thing is I saw it along the Delaware river just north of Easton Pennsylvania with my family. I took note because it seemed aggressive and it ran near my stepson. It’s size was large to me at the time, seemed to be rough guess 6 to 8 inchest long but looks exactly like the picture.

    Reply
  8. I’m 64 and as far back as I can remember my family gathered these for bait. The critter has skin tougher than shoe leather. Accordingly it’s not unusual to catch several fish on just 1. They were also referred to as rock lice. But regardless of the name..they are hands down one of ..if not the best .. bait in the stream.

    Reply
  9. I saw one of these in vermont while trying to find a crayfish to use as bait…..it was under a rock tried to get a pic but lost it in the Rapids I didn’t want to touch it cause didn’t know what the he’ll it was

    Reply
  10. We always called them leatherheads where I grew up in northern California. They are great for catching trout in the creeks. We always called salmonfly nymphs hellgermites.

    Reply
    • Thanks for providing an alternative spelling for Hellgrammite, a name with a murky origin, though the sound of the name is quite fitting for the creature.

      Reply
  11. They live under rocks along the South Branch of the Potomac in WV. The big ones are ugly and scary. They fly toward flourescent lamps in gas stations at night.

    Reply
  12. So is it a Hellgramite? We just caught one in my garage and I need to know if I should just burn down the garage or if it would be safer to burn down the entire block. So far it is still alive because none of us have the fortitude required to enter into battle with it. Really would like a solid answer as to what this thing is.
    Update: As I was typing this up my friend Taco Dave went after it with a blow torch and a throwing axe. It is still alive and well but Taco Dave is not. Well he’s alive but he is not the same person he was going into this. He is pacing around outside repeating the phrase “Ive seen things man”. Taco’s little brother Burrito Bob is suiting up next. He has chosen a garden shovel and a 5lb sledge hammer. Update coming once the battle has ended. Send help if I dont post a reply within 45 minutes. There is a school 500 yards away ,the ball field can handle helicopters and some jets with short take off and landing capabilities. If we dont reply to people yelling within 5 minutes let the napalm fly. Godspeed

    Reply
    • Omg!!! LMAO!! This was hysterical!???? I live in NE PA and just found a dead hellgrammite in my carport. Not sure how it got there? We do live near wetlands so it may have washed down the road during a heavy rain and wandered the 30ft to my carport??? Not sure what insect got to it first but it was filled with very large maggots! All that was left was the outer shell and the head!! Would’ve really liked to find it alive!!

      Reply
  13. So is it a Hellgramite? We just caught one in my garage and I need to know if I should just burn down the garage or if it would be safer to burn down the entire block. So far it is still alive because none of us have the fortitude required to enter into battle with it. Really would like a solid answer as to what this thing is.
    Update: As I was typing this up my friend Taco Dave went after it with a blow torch and a throwing axe. It is still alive and well but Taco Dave is not. Well he’s alive but he is not the same person he was going into this. He is pacing around outside repeating the phrase “Ive seen things man”. Taco’s little brother Burrito Bob is suiting up next. He has chosen a garden shovel and a 5lb sledge hammer. Update coming once the battle has ended. Send help if I dont post a reply within 45 minutes. There is a school 500 yards away ,the ball field can handle helicopters and some jets with short take off and landing capabilities. If we dont reply to people yelling within 5 minutes let the napalm fly. Godspeed

    Reply
    • Omg!!! LMAO!! This was hysterical!? I live in NE PA and just found a dead hellgrammite in my carport. Not sure how it got there? We do live near wetlands so it may have washed down the road during a heavy rain and wandered the 30ft to my carport??? Not sure what insect got to it first but it was filled with very large maggots! All that was left was the outer shell and the head!! Would’ve really liked to find it alive!!

      Reply
  14. We found two of these in Dinosaur National Monument this past weekend. We were in Utah and on the Green River. They were both long, fast and somewhat agressive. we do have a picture but its very similar to the one you have.

    Reply
  15. I saw them a lot in Virginia Madison Heights/Monroe area, especially further up in the mountains. There it’s teeming with them, and they get massive. We used to fight them lol they were pretty aggressive. I just moved to Clayton, NC, and saw one got in the house, so I think I’ll he seeing more!

    I was surprised when nobody else I showed knew what it was.

    Also I learned I was taught wrong by that kid at camp (mountains, where it was teeming haha). He told me they were “Hellkemites” and another said “Hellgamites”.

    Most everyone there did call them Hellkemites though.

    I was confused when the search engine was like wtf is this?

    Reply
  16. I saw them a lot in Virginia Madison Heights/Monroe area, especially further up in the mountains. There it’s teeming with them, and they get massive. We used to fight them lol they were pretty aggressive. I just moved to Clayton, NC, and saw one got in the house, so I think I’ll he seeing more!

    I was surprised when nobody else I showed knew what it was.

    Also I learned I was taught wrong by that kid at camp (mountains, where it was teeming haha). He told me they were “Hellkemites” and another said “Hellgamites”.

    Most everyone there did call them Hellkemites though.

    I was confused when the search engine was like wtf is this?

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    • I just saw one for the first time in 20 years of swimming in the virgin river at zion. Took a while to find out what it’s called

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