Moths are a common sight in many households and outdoor areas, often seen fluttering around lights at night. A question that might come to mind is whether these seemingly harmless creatures can actually bite humans. The good news is that most adult moths are not physically capable of biting you, as their primary focus is on reproducing and finding food sources like nectar source.
However, there is an exception to this – caterpillars, the larvae stage of moths and butterflies. These creatures might cause skin irritation or other reactions upon contact due to their tiny, hair-like bristles source. Although adult moths are generally harmless, it’s important to be cautious around caterpillars if you happen to come across them in your daily life.
Do Moths Bite or Sting?
Moths vs Caterpillars
Moths are generally considered to be harmless creatures. The vast majority of adult moths do not have mouths and are incapable of biting or stinging1. However, it is important to note that moths start their life as larvae called caterpillars1. These caterpillars may cause skin irritation and other reactions when they come into contact with humans2.
- Can cause skin irritation
- Have mouths and might bite
- Eventually turn into moths
Adult moth features:
- Does not bite or sting
- Does not have a functional mouth
Moths and Adult Butterflies
Similar to moths, adult butterflies do not sting2. Both moths and butterflies belong to the Lepidoptera order, and both have caterpillar life stages that can cause contact reactions, known as lepidopterism2.
|Moth Caterpillars||Butterfly Caterpillars||Adult Moths||Adult Butterflies|
Some examples of harmless adult moths include the luna moth and the common millers3. Contrarily, vampire moths and calyptra moths like to feed on blood, but they rarely bite humans using their spiky proboscis4. Pestilent moths, such as the army cutworm, can be annoying when they get into homes, but they do not pose a threat since they do not breed indoors3.
In conclusion, moths and adult butterflies are generally harmless to humans, while their caterpillar life stages can cause skin irritation or allergic reactions. Overall, most moths and butterflies do not bite or sting, and pose no significant danger to humans2.
Moth-related Irritation and Allergies
Caterpillar dermatitis, also known as erucism, is a skin irritation caused by contact with the spiny hairs of certain caterpillars. These hairs can break off and embed themselves in the skin, causing symptoms like:
A well-known example of a caterpillar causing dermatitis is the browntail moth caterpillar, an invasive species found only on the coast of Maine and Cape Cod. Its tiny poisonous hairs can cause reactions similar to poison ivy in sensitive individuals.
Allergy-like Reactions from Moths
Moths themselves do not bite or sting, but they can still cause some irritation and allergic reactions. These can manifest as:
- Itchy or watery eyes
- Rash or hives
- Breathing difficulties
The allergy-like reactions are mostly caused by contact with moth scales or dust, which can become airborne and inhaled or come into contact with the skin. Moths are not typically dangerous, but sensitive individuals should take precautions to minimize exposure.
|Caterpillar Dermatitis||Allergy-like Reactions from Moths|
|Cause||Spiny caterpillar hairs||Moth scales and dust|
|Symptoms||Redness, swelling, itching, blisters||Sneezing, itchy eyes, rash, breathing difficulties|
|Example||Browntail moth caterpillar||General moth exposure|
Moths as Pests
Clothes moths are notorious for damaging natural fibers in your wardrobe, such as wool, cotton, and furs. They are drawn to dark, undisturbed spaces, and their larvae can chew through fabric.
To prevent clothes moth infestations:
- Clean your wardrobe regularly
- Use cedar blocks or sachets
- Store clothes in airtight containers
Pantry moths can infest grains, cereals, and flour, making them undesirable pests in the kitchen. They are especially common in stored food products and can easily taint food.
Pantry moth prevention methods include:
- Storing grains in sealed containers
- Keeping cereals refrigerated
- Routinely cleaning cupboards and pantry shelves
Garden moths may be a nuisance to gardeners, as some moth species’ larvae can cause damage to plants and fruits. For example, spongy moths can defoliate trees and harm vegetation.
Some garden moth prevention measures include:
- Using insecticides approved for garden use
- Introducing natural predators to the garden
- Installing moth-zapper or mosquito-killer devices
Fruit-piercing moths can cause significant damage to commercially grown fruits. Their larvae bite into fruit and feed on the pulp, which can lead to spoilage and loss in crop yield.
To protect crops from fruit-piercing moths:
- Utilize pheromone traps
- Implement biological control methods
- Schedule regular crop inspections
Preventing Moth Infestations
To keep moths at bay in general, take the following precautions:
- Seal gaps and cracks around doors and windows
- Use vinegar to clean surfaces and ward off moths
- Schedule regular inspections by a pest control service
Moth Behavior and Natural Defenses
Moths are mainly nocturnal insects, which means they’re active at night. They’re characterized by:
- Antennae: Feathery structures for sensing their environment
- Scales: Delicate, dust-like particles that cover their wings
Nocturnal moths play a role as pollinators by feeding on nectar from flowers. These flowers usually have traits such as:
- Pale or white color
- Copious, dilute nectar
Some moths are also known to be active during daytime hours.
Poisonous Plants and Moth Caterpillars
Moth caterpillars feed on leaves from various plants. Certain species consume leaves from poisonous plants, which can cause adverse reactions when touched. Contact can lead to skin or systemic reactions (called “Lepidopterism”), even though the adult moths themselves don’t bite or sting.
Predators and Prey
Moths face predation from various animals, including:
Moths have several strategies to defend themselves:
- Toxins in caterpillars
- Spiny hairs
|Pros and Cons of Moth Pollination||Comparison|
|Contributes to plant reproduction and diversity||Sometimes consume garden plants, fruits, and leaves|
|Assists in the production of fruits and seeds||Can be a source of allergens for sensitive individuals|
In summary, despite moths not biting or stinging, they do have some negative aspects due to their feeding habits and toxic attributes in caterpillars.
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 – Dark Spotted Palthis
My husband and I are building a house in the middle of the woods in Lancaster, Ohio. Being new to the country environment, I have been both frightened and amazed at the creators and critters that live in the woods. I recently found your site while trying to identify a snake outside my back door, and have been able to put a name to a variety of these critters that have made there presence know to me. This one, however, seems to be rather elusive, as I have not yet been able to find it’s photo or give it a name. Although not more than 1/2 – 3/4 inch long, it has a rather strange spaceship-like appearance. I found it on the side of the house in mid September as I was putting on the siding. Do you know what it is? … Thanks,
We are not really convinced that this is one of the Snout Moths in the Superfamily Pyraloidea and Family Crambidae, but that is our best guess at the moment. We are late for work and haven’t the time to research further this morning. Perhaps one of our readers can provide a definite answer.
Well, I recognized the moth, so I went to Bugguide and by shear luck I found it: The “dark-spotted Palthis,” Palthis angulalis, is the most likely candidate. Certainly it is in the Palthis genus (family is Erebidae, one of the Noctuoidea moth families, unrelated to crambids).
It’s a “deltoid” noctuid in the subfamily Herminiinae, in the genus Palthis, most likely (judging from where it was found) the Dark-spotted Palthis (Palthis angulalis). The forewing markings are out of focus (but a great shot of the head!) so I can’t be 100% sure, but the second species in the genus occurs farther south from where this one was photographed.
A Slightly Different Opinion
Hi What’s that Bug People:
I’m an aspiring entomologist/arborist from Shelton, CT and decided to try my luck with the unknown moth. I think I found it…the Faint Spotted Palyhis, Palthis asopialis. Looks like it is in residence in Ohio. Let me know if I’m right if you have time, or post my email in an update. I check the site practically everyday, you rock! Thanks for entertaining me and scaring the crap out of my husband. Sincerely,
Letter 2 – Datana species
can you identify this creature?
I’m not sure if this is a moth or a bat, but it looks like a dead leaf. If you could identify this, I’d really appreciate it. It was about one inch long. Please see the attached photos. Thanks,
This is a moth in the genus Datana. They have very distinctive caterpillars that have unusual colorations, patterns, and postures.
Letter 3 – Delicate Cycnia
Pic of Delicate Cycnia Moth
Daniel, Offering you this pic of what I believe is a Delicate Cycnia Moth, Cycnia tenera. Didn’t see one on your site. Hope you like it.
Union Bridge, MD
Hi again Larry,
Nice research. We are happy to add to our data base with this Tiger Moth that feeds on milkweed and Indian hemp.
Letter 4 – Elyria Canyon Moth Night: July 27, 2013
2nd Annual Moth Night
July 27, 2013
Location: Elyria Canyon Park, Mount Washington, Los Angeles, California
The Mount Washington Homeowners Alliance partnered with the Santa Monica Mountains Conservancy, the Mountains Recreation and Conservation Authority and What’s That Bug? on the second annual Moth Night on the evening of Saturday, July 27 in Elyria Canyon Park. Julian Donahue, retired lepidopterist from the Natural History Museum of Los Angeles County and Mount Washington Homeowners Alliance President Daniel Marlos co-hosted the evening. The night began with Julian giving a crowd of approximately 50 excited participants some scientific background on moths and their place in the complex ecosystem of plants and animals, including significant predators. Julian also explained why moths are attracted to lights and discussed the black light and mercury vapor lights being used to attract the moths.
Once the sun set and darkness descended, the creatures of the night began to emerge, and the crowd was thrilled as the sighting of a pair of Great Horned Owls perched in a dead walnut tree and the crowd was mesmerized by the nighttime web building activities of a large nocturnal orb weaving spider. Then the artificial lights began to attract a variety of small moths and other insects, and excited began to mount among the dozen youngsters, their parents and other adults present at the event.
Though the larger moths that were hoped for including Sphinxes and the Black Witch never materialized, a wealth of small and colorful moths representing the families Tineidae, Tortricidae, Pyralidae, Noctuidae, Acrolophidae and Geometridae. Of especial note was a beautiful tortricid moth with the metallic band across the forewing, the Filbertworm Moth (Cydia latiferreana). The larvae feed inside acorns (small holes in hollow acorns are where the adults emerged), Catalina Cherries (present in Elyria Canyon) and quite possibly on SoCal black walnut nuts, although this may not have been documented yet. Another tiny gem was a small pyralid, Dicymolomia metalliferalis, that held its wings with their double staggered row of silver-crowned black spots in a tent-like manner over the body. The larvae are reported to feed in the seedpods of lupines.
Julian and Daniel look forward to hosting additional nighttime events in Elyria Canyon Park to further expose the curious public to the wealth of life that abounds in one of our local open, natural habitats.
Letter 5 – Euprepia oertzeni from Israel
I thought this one was cool
I believe this one is a Euprepia oertzeni, thought it was cool, and wanted to share. Thanks,
Tel: (202) …
Thanks for sharing your photo, but you really didn’t share much else. We were not familiar with this species, so we googled the name your provided. All indications are that it is an old world species. We then googled your area code and it is Washington D.C. We don’t know if you took this photo in our nation’s capitol, or on a vacation abroad, or if you even took the photo. Our readership thrives on information, not just lovely photos.
I actually live in Jerusalem, Israel. I found it in my kitchen, and had absolutely no idea what it was, so we nicknamed it the cow moth. I found a bug identification website, and Bob Patterson of the Moth Photographers group gave me this link: http://www.nature-of-oz.com/arctiidae.htm I have no idea what eupropia eortzeni means, but the hebrew word for it is dooboan menumar, which means leopard moth. Apparently it belongs in the Arctiidae category. Thanks,
Letter 6 – Fanmail from a Homebody
Thanks for the amazing site!
April 6, 2010
Being homebound from illness can be very, very boring. I decided to use this time to do something contructive, overcome my fear of some insects (namely moths). I had no idea how thrilling the world of Entomolgy is and really, how downright cute most insects are. You folks do good work, I applaud you. When medical bills aren’t causing me to live in poverty, I will make a donation for sure!
Stircrazy in Washington
Thanks for the kind message. We wish you a speedy recovery, because even with internet connectivity, cabin fever is no fun.
Letter 7 – Day Flying Moth from Solomon Islands
December 16, 2009
I tried sending these photos last week but I don’t think they uploaded so I’m trying again. I encountered these butterflies while hiking along the Tenaru River near Honiara in the Solomon Islands. These images are frame-grabs from a video. Hope you can help identify them.
Bruce Carlson, Atlanta
Solomon Islands, Guadalcanal
The quality of two of your images is quite poor, with cropping lines, and we would request that you resend them without the marks, one at a time, and with any description that is relevant. Our already confusing archives are easier to organize if individual species get their own postings, or if postings are confined to closely related species. Meanwhile, we will post the image of the unknown yellow butterfly in the hopes that one of our readers is able to identify it. We can tell you that the third image you sent contains a Milkweed Butterfly.
Thanks. The images are frame grabs from an HDV video converted to jpeg. I can try to de-interlace them and will resend as you suggest one at a time.
Thanks for your help with this!
Update from Karl
December 18, 2009
It really is a lovely creature, but I don’t think it is a butterfly. The shape of the antennae suggests that it is a moth and I think it may belong to the family Callidulidae, the Old World butterfly-moths. There are only three subfamilies and eight genera, restricted to tropical regions stretching from Madagascar to the Solomom Islands. If I am right, then this one probably belongs to one of four genera in the subfamily Callidulinae. According to Wikipedia “The mainly day-flying Callidulinae can be distinguished by their resting posture, which is the most butterfly-like, with the wings held closely over the back. Resembling the butterfly family Lycaenidae, these moths can be told apart by their antennae which taper to a point or may be very subtly clubbed.” Most species are Asian and not as brilliant as the one in Bruce’s photo, but Pagenstecher (1902; in German) described at least two species from the Solomons that are characterized as mostly yellow on the underside, with outer red bands. The underside of both wings of Callidula [=Cleis] hypoleuca is described as predominantly golden yellow with a reddish/blackish distal band, and the yellow areas marked with distinct black spots. A narrow submarginal band of pearly-white spots is also described for several species. His list and description of species is incomplete so I can’t be certain, but I think this is very close. Callidulidae images on the internet are almost all of Asian species which look very similar to Bruce’s photo, except for coloration. As an example you can check out Callidula attenuata from Taiwan. Regards.