Snakefly – All You Need to Know

In this article, we tell you everything that you would like to know about snakefly.

The first thing you need to know about a snakefly is that it is neither a snake nor a fly. It is a neuropterous insect and is closely related to lacewings. 

Snakeflies are an old species that have been around and unchanged for a long time.

As per fossil records, they have been around for more than 50 million years

Read on to get these and more interesting facts about snakeflies.


What Are Snakeflies?

Belonging to the order of Raphidioptera, snakeflies are a group of small, black, predatory insects that flourish across the world. 

The body of the snakefly has three separate segments.

The second segment, called the prothorax, is long and ends in a flattened head. The elongated prothorax lends it a snake-like appearance and, consequently, the name. 

They have thin, translucent wings with a network of visible veins, just like lacewings. Their bodies are shiny black in color, with 2 compound eyes. The larvae are reddish to gray in color. 

Evolutionary History of Snakeflies

To date, scientists have identified around 200 species of snakeflies. In fact, as recently as 2009, H. Aspöck & U. Aspöck discovered two more new species of snakeflies. 

As we said earlier, snakeflies have been around for much longer than humans, and as per the latest fossil studies, we believe they might have been here even 50 million years ago. 


Despite this, the extant snakeflies we see today are quite similar to the ones found in the Jurassic period.

Moreover, fossil records also show that there was a time when these bugs used to live in the tropical regions of the world. 

However, over time they have moved away and now live only in places where the climate is much colder. 

Today, cold weather has become a major part of their lifecycle. 

It is believed that the very change from cold to slightly less cool weather triggers their metamorphosis from larvae to adults.

Scientists are not sure when or why this happened and why snakeflies did not keep their ability to live in warmer climates.

Where Do They Live?

Snakeflies are found all over the world, mostly in colder climates.

Their distribution ranges from Europe to Asia, Africa, and parts of Central and North America.

Most of the population concentration is in East Asia. The only continents they do not inhabit are Antarctica and Australia

They are commonly found in coniferous forests, living on trees, or in the soil. Larvae nest beneath tree barks or loose piles of leaves.



What Do They Eat? 

Both adult snakeflies and larval instars are predators. They prey on smaller, soft-bodied insects, aphids, caterpillars, insect eggs, and mites. They are an important predator in the forest ecosystem and are beneficial in orchards.

Especially in pear orchards, they feed on the pear psylla – a pest that sucks out the sap from pear fruits and trees. 

Studies show pollen in the digestive tracts of snakeflies. But whether they actually drink nectar or not is unclear. Their behavior is territorial and predatory. 

What is the Lifecycle of Snakeflies

Females lay eggs that are long and cylindrical in shape. The larva that emerges is flattened, shiny, and has large, projecting mandibles.

The instar stage of the snakefly larvae is quite interesting. Unlike other insects that have a fixed number of instar stages (usually 3 or 4) – snakeflies can go through as many as required. 

They remain in the larval stage for as long as three years and can go through 10 instar stages. 

Snakefly Larva

Larvae feed on smaller insects and finally go into a pupa. The pupa is active, which means it is capable of reacting by biting or walking upon sensing danger. 

The mandible of the larvae also helps it to chew its way out from the pupae. 

Depending on the temperature, the larvae mainly remain within the pupa for many months waiting for the ideal temperature. 

When scientists subject the larvae to a constant temperature range, they sometimes end up in a stagnant state where they never undergo chrysalis. 

But under ideal circumstances, as the temperatures rise, adult snakeflies emerge.

Female snakeflies are bigger than males and have an ovipositor at the end to deposit eggs within barks or the soil. An adult snakefly is smaller than an inch

Do They Bite or Sting Humans? 

The mouthparts of both adults are larvae that are non-specialized but are strong and capable of biting. The larvae also have projecting mandibles

Having said this, they do not usually bite humans. They are beneficial for orchards and plantations as they help keep mites and aphids in check. 

However, there do exist records of people being bitten by the larvae (read the emails section)! 

If you see them indoors, just dispose of them with a vacuum. They cannot sting, though the females have an ovipositor which may look similar to a stinger. 

Square Headed Snakefly

What To Do If They Bite? 

A snakefly biting a human is quite rare. But we do have records of both larvae and adults biting our readers, and the bites are said to be quite painful. 

Adults, especially females, can be aggressive if they sense danger and resort to biting. 

While the bite can be painful, you can simply pick off the insect and dispose of it. Treat the bite with a cold compress, followed by an antibacterial solution and ointment. 

Are They Poisonous or Venomous?

Snakeflies are not poisonous or venomous to humans. Their bites are painful but do not cause any additional swelling. 

No medical visit is necessary. The pain is similar to being pricked by a large ant. However, it goes away soon, even without any treatment. 

Are They Harmful to Humans as Pests? 

Snakeflies are not considered pests. Pests attack plants and crops, feeding on fruits, flowers, and plant sap. 

They are predatory and do not harm crops in any way. On the contrary, they are a good addition to your garden since they eat up smaller pests. 


Are They Beneficial?

Generally, they are beneficial for gardens, plantations, and orchards. They destroy the eggs, larvae, and pupa of many smaller insects like mites and aphids, which feed on plant sap. 

A good garden ecosystem will have enough of these predatory insects to keep the crops in check. 

Can They Come Inside Homes?

It’s quite possible for adult snakeflies to fly into homes. If you happen to see some, do not touch them with your bare hand. It’s best not to squash them. 

Instead, use cardboard to swat them away and dispose of them outside. In gardens, you can spray insecticides on plants if you suffer from a snakefly infestation. 

The insecticide will kill their food source and eventually starve the snakeflies. 

What Are They Attracted To?

Snakefly adults are nocturnal. They are attracted to light. This could be one of the reasons why you end up finding some in your home. 

Scientists also use pheromones that attract them to trap them in black boxes and use them for studies. 

How To Get Rid of Them? 

Ideally, you need not get rid of snakeflies. If they enter your home, the first step should always be to remove them from there and leave them in the garden. 

To prevent them from entering your home, seal all crevices and use screens on your windows. Put a mesh around any other opening or ventilation space. 

However, if there is an infestation in your garden, you can spray your plants with a narrow-spectrum insecticide. 

The lack of smaller insects as food will cause the snakeflies to starve or move elsewhere. 

You can also spray the insecticide on tree bark or the top soil layer where the adults lay their eggs. 

But beware – that lack of predatory insects can cause plant-eating insects to rise in number once the insecticide wears off. 

Interesting Facts About Snakeflies

  1. Snakeflies have been around since the Jurassic period.
  2. They are very clumsy fliers. Their flight patterns are unruly, and they often bump into things.
  3. Snakeflies lick themselves thoroughly before mating in an effort to groom themselves!
  4. Snakefly larvae can move both forward and backward using a process called undulation.

Frequently Asked Questions 

What does a snakefly do?

Snakeflies mainly spend their lives feeding on other insects. Both adults and larvae are predatory and pretty good ones at that. 
They are very territorial and aggressive, even during the pupal stage. The pupa can even bite if disturbed!

What do snake flies look like?

Larval snakeflies have a dark red to gray segmented body with a large mandible. Adults are black with an elongated thorax and a flattened head. 
Their wings are transparent, riddled with veins, and form a roof-cover-like structure when they rest. 

Can a snake fly in the sky?

All species of snakefly adults have papery thin wings that allow them to fly. However, they are weak flyers and mostly focused on hunting than flying in the sky. 
Larvae look very different from adults. They are wingless and flightless.

Are drain flies harmful to humans?

Drain flies are commonly found grey flies that breed in moist areas like sinks and sewers. They cannot bite or sting and are non-toxic. 
However, they carry pathogens from foraging around in the trash and can transfer those to humans. They can also cause allergic reactions. 

Wrap Up

Snakeflies are found in abundance but are still interesting insects to study. They are one of the few insects that can form a pupa that is capable of biting and movement. 

Their lifespans are long, and the larvae can keep growing until a suitable season for pupating. There are still ongoing studies to know more about them. 

Thank you for reading.

Reader Emails

Their unique appearance and rich history have meant that snakeflies have always had admirers in the bug lovers community.

Read through some of the emails below from our readers, and the pics and .

Letter 1 – Snakefly


You mentioned that you didn’t have a lot of photos of Snakeflies. Here’s a great shot that my son took with a digital camera of a Snakefly on an 3/16 inch diameter irrigation drip tube. We didn’t know what it was when he took the picture and he named it the “Dragon Bug”.

Hi Bill,
Thanks for sending in a wonderful photograph.

Letter 2 – Snakefly


Howdy there!
Just discovered your excellent site and really enjoyed all the hard work you have done putting the wonderful site together. I wish there was an identical site for flowers and plants. There are a few close ones but nothing as easy and extensive as yours. I have always enjoyed learning about insects and the rest of the critters around us every since I was able to talk I think. Should have done it for a living but here I am doing what I can to share the knowledge of such things. It is with great appreciation to have a site like yours to search and share alike. Thank YOU! As a graphic designer and web designer I am with an understanding of what it takes to pull off the task you guys are managing. I also have a freelance blog with the local paper here in Redding, California which today I included a link to your wonderful site.
Thanks again and feel free to use the attached images if you like.
Best regards,
Duane Langshaw

Hi Duane,
Thank you for your glowing compliments and also your wonderful photo of a Snakefly.

Letter 3 – Snakefly


I took pictures of this bug and then was able to identify it using your website. When I saw the word ‘Snakefly’ I knew I had my bug. For once, something was aptly named. I observed this bug for awhile before I let it go. It was fascinating. It hop-flies. I used my crummy little digital to get a picture of it. I improved upon the macro by taking the picture through a jeweler’s loupe. It worked great! He started posing for me, I swear. Here’s the pic. Thanks for your website. You’re a gem!
Kay Herndon
Spicewood, Texas

Hi Kay,
We are very impressed that you properly identified your Snakefly through our site. Thank you for the sweet letter and also your great photo. We haven’t many Snakefly images and your is a welcome addition.

Letter 4 – Snakefly


“Giraffe” bug?
Hi there,
I encountered this interesting bug on a recent hike, and would LOVE to know what the heck it is. Thanks for your time and your excellent service.

Hi Numlok,
We were a little too busy to answer mail yesterday, and we are thrilled that you used the site to identify your Snakefly without any further assistance from us.

Letter 5 – Snakefly


What’s this bug? lol
I got the link to this site from the GardenMessenger Group on Yahoo and have just become so fascinated with your site. Lots of great info. Well, I came looking because I found a bug I’ve not seen before and it seems to frequent my passion flower vine and fuchsias. The passion vine seems to be getting nibbled more so. From looking at your site, I’m guessing it is some kind of Ichneumon Wasp. The photo I managed to get is of one with a slightly thicker body. I’ve seen others that are completely twig thin. The necks are also elongated with the head at the end. Anyway, picture is enclosed, and am wondering if this is the leaf-eating culprit or if it’s good at eating the leaf-eaters. Oh, and I’m in Spokane, Washington if that helps too.
Best Wishes and Thank You-

Hi Andrew,
Your insect is a Snakefly from the family Raphidiidae, within the Nerve Winged Insect Order Neuroptera. Adults are predators, not plant eaters. They are probably helping to control the aphids and scale insects on your plants.

Letter 6 – Snakefly


Weird bug looks like a dobsonfly and yellow jacket mixed
My wife and I found this bug in our house on the curtains. I have never seen one before so there’s no worries or anything, I was just curious and wanted to find out what it was. I looked all over the internet and can’t find it, but after coming across your site, I figured maybe you could help? We live in the Willamette Valley in Oregon. I saw pictures of dobsonfly’s and it looks similar to that but it has a longer neck and a body like a yellow jacket with a long tail (maybe a stinger???). I look forward to hearing from you!
P.S. Thanks for the great website, I find it very fascinating! 🙂

Dear Andy,
You have taken a photograph of a Common Snakefly, Agulla species. They can be recognized by their elongated prothorax and projecting head. Adults feed on small soft-bodies insects including young scale insects, aphids and mites, and are beneficial to farmers and gardeners. They are members of the order of Nerve-Winged Insects, Neuroptera that also include Dobsonflies.

I got busy and never had a chance to reply and thank you. Thank you for identifying the insect and replying so quickly! I love your site and hope you continue to run it for years to come. You provide a very unique and excellent service. Thanks again.

Letter 7 – Snakefly and Tips on Getting our Attention!!!


Strange dinosaur bug in Carmichael CA —–What could it be?????????????
I found this winged bug sitting on my car’s window this afternoon. It immediately caught my attention because -seriously- it looked reptilian. It’s colors were dark green, yellow and it had orange legs. It really looked like it had scales. It’s neck and antenna are long and it has a long tail too that I thought at first was a stinger. But the longer we looked at each other the more I started to doubt that that’s what it was. Anyway, as soon as I saw this little guy, I thought of you and ran back upstairs to get my camera. I’m sending you several images of it. Sadly, the image from the side is blurry -my camera just couldn’t focus. But I’m sending it anyway because you can still see the arch of it’s long tail. I know you guys can’t answer every email but please answer mine? This bug is just so pretty! And I really want to know what it is. The way it moved was just so graceful! It’s long neck seemed so flexible when it would bend and it’s little head was just so…let’s just say that it was checking me out as much as I was checking it out! It was so cool. Please help me identify it? Thanks so much! I love your site!!!!!!!
Jen in Carmichael CA

Hi Jen,
It is true that we cannot answer every email. We are not proud to admit it, but when we get swarms of emails, and our real lives cannot allow us the luxury to post to the internet, we delete many emails without even opening them. No subject in the subject line will most certainly wind up in the trash. You, on the otherhand, know how to catch our attention. How could we even try to ignore a letter that starts with “Strange dinosaur bug in Carmichael CA —–What could it be?????????????”? The answer is we just can’t. Another big pet peeve of ours is not including a location, and your letter even included that in the subject line. Catching our attention when we are scanning letters can be likened to a one sentence pitch for a movie script. You need to grab our attention and intrigue us. You Jen, did just that. Before we even opened the email and read it, we started to wonder just what bug you thought looked like a dinosaur. Well, this is a female Snake Fly. The tail is her ovipositor. Snakeflies are Neuropterans, and there are some other monstrous members in the order. Just take a look at our Dobsonfly page. Snakeflies are in the suborder Raphidiodea. Thanks for a descriptive letter that is fun to read, a catchy subject line, and a nice photo to complete the package. This is our favorite type of letter to post.

Letter 8 – Snakefly


new bugs
Enclosed are a few things I thought you might like. The first is an interesting little grasshopper I found at work with very long back legs. The second is a TINY praying mantis nymph I found right outside my door. The third is something I’ve never seen before, and I have yet to locate one on your website. I have no idea what it is, but I would chance that it is female, as it has an enlarged abdomen and a possible ovipositor. I would love to know what this is. I really like it, and it’s one of the better pictures I’ve taken. Any help would be appreciated. Thank you!

So I looked around some more, and I guess that it’s a snakefly. I had never heard of them before, but I finally came across it because I realized it reminded me of a lacewing. Oh well. In any case, I hope you like the picture! Thanks!

Hi Cat,
We are very happy to hear that our site enabled you to identify your own Snakefly. We love promoting research empowerment. Your photo is also a much welcomed addition to our site.

Letter 9 – Snakefly


Winged But with Long Neck
Sat, Feb 28, 2009 at 11:43 AM
Hi! I’ve seen this guy three times in the last week and finally got him to sit still for a picture. He seems to be alone, there is no swarm. He hangs out on walls and flies only as a last resort. We’ve just had some spring rains, so maybe that has something to do with his appearance now. Thanks for your help!
Santa Barbara, CA


Dear STW,
Over the years, we have had countless letters from people who want buts identified. Perhaps it is the proximity of the g to the t on a keyboard. This is a Snakefly. Snakeflies are in the order Raphidioptera and according to BugGuide: “Formerly Raphidioidea, a suborder of Neuroptera. ” That means we need to reclassify all the Snakefly postings on our site to conform to the new taxonomy. Adults and larvae are both predatory.

Dear Daniel,
Thank you so much for the Snakefly info.  And I also appreciate your kind treatment of my lack of typing skills!
You’ve got a great site.


Letter 10 – Snakefly


Unknown Northern California Bug
Sun, Apr 5, 2009 at 3:06 PM
Hello. We live in Palo Alto, CA and have recently stumbled across this ugly bug. It is approximately an inch long, has what looks like a stinger, long wings, and a long neck. My husband thought it might be a sort of baby praying mantis, but after looking at it longer, we agree it must be something else. Does it sting is my question. We recently had a really bad gnat problem on our balcony and I feel like these bugs are living off of the dead gnats. Here is a picture, I hope it helps!
Concerned Stanford Family.
Palo Alto, California, USA


Dear Family,
There is no cause for concern or alarm.  This is a Snakefly in the insect order Raphidioptera.  Both larval and adult Snakeflies are predators so they are beneficial insects.  The “stinger” is actually the ovipositor of the female insect, and is used in the egg laying process.  It is not an organ of defense and the Snakefly does not sting.

Letter 11 – Snakefly


Jaws of a beatle, wings of a cicda, and a needle like tail?
Wed, Apr 8, 2009 at 12:59 PM
I happened to notice something in my door jamb so I grabbed my camera a took a couple of photos. I didn’t mess with it because it looked like it could bite or sting me, lol. I live in Concord, CA and there is an abundence of insects that I have never seen. This being the most interesting one I’ve ever seen. I hope the image will provide enough info for you.
Thank you so much for looking, Brodie
Northern California Concord, CA


Hi Brodie,
This is a female Snakefly in the order Raphidioptera.  Snakeflies are harmless predators and the stinger is actually the ovipositor of the female insect.

Letter 12 – Snakefly


Long neck, not a mantis?
Sun, Apr 19, 2009 at 6:41 PM
Stanford university, tall grass, mixed oak woodland, middle of a hot spring day. On my leg, probably from the grass.
Dave H
Palo Alto, Ca, USA


Hi Dave,
This is the third Snakefly image we have posted from California in a short period of time.  Perhaps it is a more plentiful year for this harmless predator, or perhaps people are just more closely observing the other creatures we share this troubled world with.

Letter 13 – Snakefly


Weird Flying Insect
Tue, May 12, 2009 at 10:23 AM
I was in Reseda, California on Sunday which is in Los Angeles and a strange bug caught my eye. It landed on a bright pink table cloth and started walking around. i noticed it’s long stinger and pattern on it’s wings and quickly grabbed a camera, It did not mind me coming in close, so I shot a few images.
It may be very common, but I have not seen anything like it before. What is it?
My kids would like to know too 🙂
Joel Lipton
Los Angeles, Ca


Hi Joel,
What a wonderful photo of a Snakefly in the order Raphidioptera.  The subject has such personality.  These are very distinctive insects and they are not easily confused with anything else.  Your female has a stinger-like ovipositor.

Letter 14 – Snakefly


What is this one???
April 12, 2010
Hi, I hope al is well I sent a message a week ago. But, did not get response regarding a bug that I am trying to identify? Is this a Mantis or a Termite
Thousand Oaks (Southern California)


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