Bristletail: All You Need to Know in a Quick Guide

Bristletails are fascinating insects with a rich history dating back millions of years.

Belonging to the family Machilidae, these ancient critters have left their tracks in Permian rock, which is between 290 and 248 million years old.

With a global presence, there are approximately 350 to 450 species of Bristletails, and they can be found in diverse habitats, from the Arctic to the desert.

Known for their distinctive three long tail-like appendages at their hind end, Bristletails often dwell in leaf litter, bark, and rock crevices.

Though they usually live outdoors, they can sometimes become a nuisance when they enter homes, especially in damp areas such as kitchens and bathrooms.

For those intrigued by the incredible world of insects, understanding Bristletails provides a glimpse into the evolutionary history of these captivating creatures.

As you delve deeper into the topic, you’ll discover just how remarkable these insects are and the adaptations they’ve developed to survive in various environments.

Bristletails: What Are They?

Origins and Classification

Bristletails, belonging to the group Archaeognatha under the class Insecta, have ancient origins.

Tracks of these insects can be traced back to the Permian period, nearly 290 to 248 million years ago.

They are closely related to silverfish, yet, silverfish falls under a different group, called Zygentoma.

Physical Characteristics

• Bristles: Bristletails and silverfish both have three long tail-like appendages, which give them the name “bristletails.”
• Body appearance: Both have elongated, flattened bodies.
• Size: Range from 0.5 to 2 centimeters in length.

Wingless Insects

Being wingless insects, bristletails navigate through their habitat by jumping or crawling.

They reside in diverse environments, from the Arctic to the desert, and are commonly found in leaf litter, bark, or rock crevices.

In contrast, silverfish are typically found in moist areas such as kitchens and bathrooms when they enter homes.

Comparison Table

Aspect	Bristletails	Silverfish
Group	Archaeognatha	Zygentoma
Habitat	Leaf litter, bark, rock crevices	Moist areas like kitchens, bathrooms
Size	0.5 to 2 cm	Similar to Bristletails
Bristles	Three long tail-like appendages	Also have three tail-like appendages
Wings	Wingless	Wingless

Behavior and Habitat

Adaptive Features and Abilities

Bristletails are wingless insects with several unique adaptive features and abilities, which help them thrive in a variety of environments.

Some of these features include:

• Long antennae for sensing their surroundings, even in dark crevices
• Light-reflecting scales for camouflage
• Powerful legs that enable them to jump considerable distances

These adaptations make Bristletails well-suited to explore and live in different types of habitats.

Range and Habitats

Bristletails belong to the order Thysanura, which includes two main families: Machilidae and Meinertellidae.

Both families have a wide range of habitats:

• Machilidae prefer areas with higher humidity and can often be found in soil, leaf litter, underneath stones, and around moss and lichen
• Meinertellidae are mostly found in drier environments, such as crevices and decaying plant matter

A common feature in the habitats of Bristletails is the presence of algae, which serves as their primary food source.

Additionally, they can be found living alongside other small invertebrates, such as springtails and ticks.

Here’s a brief comparison of the two main Bristletail families:

Family	Habitat Preference	Food Source
Machilidae	Humid environments	Algae
Meinertellidae	Drier environments	Algae

While Bristletails may not be widely known, understanding their adaptive features, abilities, and habitats contributes to our broader knowledge of the insect world and the diverse range of creatures that inhabit our planet.

Diet and Feeding Habits

Natural Sources of Food

Bristletails are small insects that primarily feed on:

• Lichen
• Moss
• Other organic material

They also consume other small arthropods such as:

• Arachnids
• Mites
• Flies

Their mandibles are well-adapted for breaking down their food, allowing them to process different sources like lichens and mosses effectively.

Infestations in Human Structures

Bristletails can sometimes be found in human-made structures. In these cases, their diet may include:

• Cereals
• Books
• Paper
• Wallpaper

This can lead to damage to valuable items and structural materials. To prevent bristletail infestations, it’s crucial to store cereals and similar products properly and maintain low humidity levels in buildings.

Identification and Classification

Physical Features

Jumping Bristletails are ancient insects with some unique physical features:

• They have elongated, cylindrical bodies.
• Their head has compound eyes.
• They possess three distinct tail-like appendages called cerci.

These traits help in their identification and classification within Class Insecta.

Subgroups

There are two families of jumping bristletails, with about 20 species found in North America:

1. Family Machilidae
2. Family Meinertellidae

These families comprise 350 to 450 worldwide species, residing in various habitats like leaf litter, bark, rock crevices, and Arctic to desert environments.

Related Species

Comparing jumping bristletails to some related species:

Insect	Features
Jumping Bristletail	Elongated body, cerci, compound eyes, ancient lineage
Silverfish	Wingless, flat body, similar to bristletails, found indoors

For further science and image galleries on jumping bristletails and their related species, visit the respective links provided.

Reproduction and Life Cycle

Sexual Maturity and Mating

Bristletails reach sexual maturity after several molting cycles. Males deposit a spermatophore that females pick up to fertilize their eggs.

Firebrats:

• Reach maturity faster
• Prefer warm habitats

Silverfish:

• Mature slower
• Can inhabit cooler areas

Molting Process

Bristletails go through numerous moltings even after reaching sexual maturity. Molting allows them to grow and repair damaged tissues.

Molting process:

1. Bristletail stops feeding
2. Old exoskeleton splits
3. Bristletail emerges
4. New exoskeleton hardens

Comparing Firebrats and Silverfish molting:

	Firebrats	Silverfish
Frequency	More frequent	Less frequent
Habitat	Warm environments	Cooler environments

Life Span of Bristletails

Bristletails have evolved to have a relatively long lifespan compared to other small insects.

Their lifespan consists of the following stages:

Egg: The eggs take several weeks to hatch, depending on environmental conditions.

Nymph: Once hatched, the young Bristletails resemble miniature versions of the adults but lack some of the mature features.

This nymph stage can last for several months to a year, depending on the species and environmental factors.

Adult: As adults, Bristletails can live for several years.

In total, depending on the species and environmental conditions, a Bristletail can live anywhere from 3 to 7 years, making them one of the longer-lived insects.

Prevention and Control

Environmental Coping Measures

Bristletail prevention begins with environmental coping measures.

Reducing moisture levels in various areas such as floors, walls, and humid environments is crucial.

Use a dehumidifier or increase ventilation to combat high humidity.

Address spills and excess liquid promptly to avoid attracting these arthropods.

Seal any cracks in walls and floors to prevent bristletails from entering indoor areas, especially kitchen areas and near the refrigerator.

Predators of Bristletails

Due to their small size and ground-dwelling nature, bristletails face a variety of predators and threats in their natural habitats.

These predators can be used to remove them easily.

• Spiders: Many spider species prey on Bristletails, using their webs to trap these insects or actively hunting them in leaf litter.
• Birds: Ground-dwelling birds, especially those that forage in leaf litter or bark, often consume Bristletails as part of their diet.
• Ants: Some ant species, especially those that hunt individually, can overpower and consume Bristletails.
• Centipedes: These agile predators often hunt Bristletails in the same habitats, using their venomous bite to subdue their prey.

Chemical Methods for Eradication

When it comes to eradicating bristletails, insecticides can be useful. Apply these chemicals to crevices and corners where bristletails may hide.

Be cautious around food preparation areas, and consider using glue traps as a non-toxic alternative around kitchen spaces.

Method	Pros	Cons
Insecticides	Effective	Can be toxic; may harm other wildlife
Glue Traps	Non-toxic	Limited coverage; may not be effective for large infestations

Remember, bristletails, also known as silverfish, are small arthropods characterized by:

• Three long tail-like appendages, called cerci and styli
• Lack of wings
• Compounded eyes absent or reduced, along with ocelli (simple eyes)

By implementing a combination of environmental coping measures and chemical methods, you can effectively prevent and control bristletail infestations in your home.

Conclusion

Bristletails, ancient insects with a lineage dating back to the Permian period, offer a captivating glimpse into the evolutionary journey of arthropods.

With their distinctive three tail-like appendages and a preference for habitats ranging from leaf litter to rock crevices, these creatures have adapted to diverse environments worldwide.

While they primarily feed on organic materials like lichen and moss, they can sometimes venture into human habitats, necessitating preventive measures.

As we explore the world of Bristletails, we gain a deeper appreciation for the intricate web of life and the myriad species that have stood the test of time.

Reader Emails

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

Letter 1 – Bristletail and a Mouse Encounter

Subject:  What’s That Bug?
Location:  Ventura, California
April 28, 2017
Dearest Bugman,
I live in Ventura, Ca a small coastal city about an hour north of LA. My home is on the hillside and I enjoy the small ecosystem in my neighborhood with a variety of birds (some of which sing morning and night), lizards, other critters I often do not encounter inside my home and a large variety of “bugs” of all types.

I often have silverfish in my home and my practice is to acknowledge them and let them be, but I spotted this guy the other night on my kitchen floor and he looked a little different. I got down on the floor for an intimate photoshoot with this little fella, and also noticed that when I got close he would flutter small wings, but never really took flight.

I snapped these shots with my iPhone and hopefully got enough details for you to determine just who my new friend is…  30 seconds after I switched off the kitchen light and sat down in the other room (with a view of the kitchen) I saw a mouse run across the very kitchen floor I had just been down and dirty on!

Of course I screamed as this was my very first ever experience of any type of four legged animal in my domicile. I considered leaving for the evening and returning in daylight hours, but decided that it is my home and I will be a decent hostess even to the most unsavory of uninvited guests for a night or two.

It took 3 nights and about 15 have a heart traps set in my kitchen by a professional, but the good news is it appears that there are no longer unwanted mammals in my home… which brings us back to the question at hand: have you seen this before?
Signature:  Melanie On the Irish Chain

Dear Melanie on the Irish Chain,
The Bristletail in your images is a primitive insect that was once classified with Silverfish and several other groups that have since been taxonomically divided, with Bristletails now being classified in the Order Microcoryphia. 

BugGuide has some wonderfully detailed images of Bristletails.  Based on this BugGuide information on habitat:  “outdoor grassy or wooded environments: under bark, in leaf litter, rock crevices, or under stones; not normally found in homes, does not breed indoors, and not considered a pest” we would not classify this posting as a Household Pest, but considering your encounter with the rodent, we feel the tag is appropriate.

Letter 2 – Jumping Bristletails

Whats My Bug?
Hello!
I hope these photos will suffice – afraid I cant seem to get a closer one. These little guys show up every time we put the sprinkler on or when it rains.They are in our house – as well as being all over outside. These little guys look grey, but have a very pretty gold to them in the sunlight.

They are about 1/2 inch long. They are soft bodied and don’t seem to have a “shell”. They like to jump – about 2-3 inches – when you disturb them. They seem to like darkness and move a lot during the night. The top right photo is a scan of the underside of the bug.

The rest are digital pictures taken with a webcam. I live in Williams Lake, British Columbia, Canada, and I appreciate any insight you might have as to identifying and controlling (read: keeping out of basement!) these little guys. Thanks alot!
Christina

Hi Christina,
You have Jumping Bristletails, Family Machilidae, relatives of Silverfish. They usually live under stones and leaf rubble.

Letter 3 – Bristletail

Found in my kitchen but not in my bug books
Sat, Mar 7, 2009 at 4:25 PM
I found this guy trapped inside a casserole bowl in my kitchen. It looks something like an earwig, but the pincers in front and what looks like likes wings on the back.
Rich Guthrie
upstate New York – near Albany

Hi Rich,
This is a Bristletail in the order Microcoryphia.  It is a primitive insect related to Silverfish.  Bristletails are nocturnal and secretive, generally found outdoors, though some species are found in houses.  Current taxonomy has Bristletails and Silverfish in distinct orders, but some old texts lump them together.

Letter 4 – Bristletail

Stumped!
Hi Daniel,
I’ve spent the last hour or so on your site, BugGuide, and other places, but I’ve obviously been looking, subject-wise, in all the wrong places.  Can you please help me identify this small one?  It’s 1¼” from tip to tip (body’s ¾”).
Thanx for being there!
R.G. Marion
Cosby, TN
Great Smoky Mountains

Dear R. G. Marion,
This is a very primitive insect that is classified in the order Microcoryphia, the Bristletails.  We don’t have many images on our site, and we lump them together with another primitive order, the Silverfish. 

BugGuide, the more scientific insect website, has them in a distinct classification and you can compare your photo to the images posted there.

Letter 5 – Bristletail

Subject: NorCal bug coming up drain (septic system)
Location: San Francisco Bay Area
November 5, 2016 12:27 pm
I’ve seen a few of these alive in my bathroom sink. They seem to be coming up from the drain. They are fast-moving, and this one is about 1.5″ long.

I live in the San Mateo hills south of San Francisco, and we are on a septic system here. These bugs have been spotted in September and October.
Signature: Adam

Dear Adam,
Based on this BugGuide image, we are confident that this is a primitive insect in the order Microcoryphia, known as a Bristletail. 

According to BugGuide:  “outdoor grassy or wooded environments: under bark, in leaf litter, rock crevices, or under stones; not normally found in homes, does not breed indoors, and not considered a pest” and their food is “algae, lichen, moss, decaying vegetation; usually feed at night.”

Letter 6 – Bristletail from Singapore

Subject: Singapore prawn-like insect
Location: Singapore
March 30, 2014 9:49 pm
Hi Daniel
If we ever needed proof that all life on earth originated from the sea then this insect surely must be it. I found it in a wooded area far away from any water source. It looks more like a prawn than an insect.

Would you have any idea what it is ? It was about an inch in length and moved quite fast. It was sitting on a leaf as you can see from the photo.
Signature: David

Hi David,
This is a primitive insect in the order Microcoryphia, and the members are commonly called Bristletails.  Compare your individual to this Rock Bristletail pictured on BugGuide. 

According to BugGuide, Bristletails are:  “wingless; body cylindrical, brownish or yellowish with darker mottling or irregular pattern; thorax arched dorsally; tip of abdomen with 1 long medial filament and 2 shorter lateral cerci; long thread-like antennae with many segments; eyes large and meet in middle; mandibles articulate at one point only; short lateral styli (rudimentary appendages) on abdominal segments 2-9; able to jump up to 10 cm by snapping abdomen against ground”

and they inhabit “outdoor grassy or wooded environments: under bark, in leaf litter, rock crevices, or under stones; not normally found in homes, does not breed indoors, and not considered a pest.”

Letter 7 – Jumping Bristletail

Subject:  Grey mystery bug
Geographic location of the bug:  Potosi, Wisconsin
Date: 10/03/2021
Time: 01:50 PM EDT
Your letter to the bugman:  So I found this critter in a shed in Wisconsin.  It’s about an inch long (maybe more).  It doesn’t look like anything I’ve seen, and it was able to hop, almost like a cricket.
How you want your letter signed:  Mark Beshel

Dear Mark,
This is a Jumping Bristletail in the family Machilidae which we identified on BugGuide.  Bristletails are primitive insects and according to BugGuide the habitat is:  “outdoor grassy or wooded environments: under bark, in leaf litter, rock crevices, or under stones; not normally found in homes, does not breed indoors, and not considered a pest”

Letter 8 – Jumping Bristletail from Switzerland

Subject: Swiss alpine bug at 4000m altitude
Location: Swiss Alps
July 30, 2016 1:08 am
What interesting bug did I see at 4000m/13000ft altitude on rocks in the Swiss alps? The pic is of the back end of the bug as it was very quick to get away.

It jumped with a distinctive flicking motion in which it arched it’s back up and down. Reminiscent of a shrimp and silverfish. Pic taken at midday on 29th July 2016, in sunshine, air temperature probably 5 degrees C.
Signature: Ash

Dear Ash,
We believe this is a Jumping Bristletail in the family Machilidae, a group of insects that are quite similar to Silverfish. 

According to BugGuide, a North American site, the habitat is:  “outdoor grassy or wooded environments: under bark, in leaf litter, rock crevices, or under stones; not normally found in homes, does not breed indoors, and not considered a pest.”  Here is a very similar looking image from Alamy. 

Awesome! Thank you so much for your story response.
Best.