Currently viewing the category: "Asps and Flannel Moth Caterpillars"

Subject:  What is this bug?
Geographic location of the bug:  Pavement, TX
Date: 11/01/2017
Time: 05:01 PM EDT
This bug has been found in front of my house and I’d like to know what it is.
It’s really fuzzy and has a white underside.
How you want your letter signed:  Thanks, Orange


Dear Orange,
This is a Flannel Moth Caterpillar, commonly called an Asp.  It is a stinging species and here is a nice BugGuide image.

Subject:  Catepillar
Geographic location of the bug:  Taboga Island, off the coast of Panama
Date: 09/22/2017
Time: 08:49 AM EDT
This specimen was photographed at my parent’s property. I know it is a moth of some type; however, I have searched unsuccessfully for a photograph of an adult specimen to inlude identification.
How you want your letter signed:  Nature Enthusiast

Flannel Moth Caterpillar

Dear Nature Enthusiast,
This is a stinging Flannel Moth Caterpillar,
Megalopyge lanata, and it should be handled with extreme caution.  According to an article on Research Gate:  “Shinney is a colloquial term used to describe a hairy caterpillar in Trinidad and Tobago. There have been at least four instances in 2010 in which people were envenomated by shinneys in the Bon Accord region of Tobago.”

Flannel Moth Caterpillar

This was not Tobago it was Taboga, Panamá, one of the many islands off the coast of Panamá; but, considered part of the country.
I am sure your identification still remains the same.
Thanks!  I will look it up now to find an adult species.  Lots of stinging catepillars in Panamá!

We did catch the difference, however, they are in the same general vicinity and insects don’t respect national boundaries anyways.  Here is a Google Maps image of the area.

I knew that!!  🙂  I had sent those pictures elsewhere and was not satisfied with their identification.
I am confident with yours and quick too!  You certainly know your insects!!
Thanks Again!!

But we didn’t and now we and our readers know the difference and distance between the two islands with transposed letters.

Subject: WTB
Location: East of Shamrock Texas
August 24, 2017 10:31 am
found on one rose bush. I have 11 rose bushes. I only spotted one of these hairy cocker spaniel looking catepillars. I wont touch it.
Signature: cowchipper

Black Waved Flannel Moth Caterpillar

Dear cowchipper,
This is a Flannel Moth Caterpillar from the family Megalopygidae, a group that contains the infamous Asp.  You were wise not to touch as many Flannel Moth Caterpillars are capable of stinging.  We believe we have identified your individual as a Black Waved Flannel Moth Caterpillar,
Lagoa crispata, thanks to this BugGuide image.  According to BugGuide:  “Caution, Hairs on caterpillar highly irritating, as in all of this family!”

Black Waved Flannel Moth Caterpillar

Subject: Caterpillar?
Location: Southeast Missouri
August 1, 2017 2:50 pm
My cousin found this in her bed one evening! She had a few spots on her arm and leg that stung. Could this be a type of stinging caterpillar?
Signature: Brittany

White Flannel Moth Caterpillar

Dear Brittany,
This is a White Flannel Moth Caterpillar and they do sting.  Here is a BugGuide image for comparison.  According to BugGuide, the caterpillars feed on “A variety of hosts reported including black locust, hackberry and redbud.”  Are any of those trees growing near your cousin’s bedroom?

White Flannel Moth Caterpillar

Subject: Black waved flannel moth
Location: Fredericksburg, Virginia
June 30, 2017 12:46 am
I’m pretty certain that these photos are of the Black Waved Flannel Moth (checking against bug guide)(and reading that you have had endless photos of them). …I got no absolute confirmation from Bugguide but there were many photos of identical moths. The information I can’t seem to find, is what relationship these moths have to the Puss Caterpillar. They seem to be separate ….there are the megalopygea opercularis and then there are the species Lagoa crispata. Both Flannel Moths? Similar looking caterpillars?.
And the Puss Caterpillar is VENOMOUS but I can’t find information on how venomous the Lagoa crispata is. Or the specific caterpillar. The internet is conflicting. Are they venomous and are they AS venomous?
Signature: Susan Warner

Black Waved Flannel Moth

Dear Susan,
All the images you provided are details.  We wish you had provided a standard dorsal view of the entire moth.  We believe your identification of the Black Waved Flannel Moth is correct, and the antennae indicate this is a male moth.  BugGuide does indicate:  “Caution, Hairs on caterpillar highly irritating, as in all of this family!”  So, the family Megalopygea includes both
Lagoa crispata and Megalopyge opercularis, but they are classified in different genera within the family.  According to an article on the Asp, Megalopyge opercularis, by David M. Eagleman on EaglemanLab:  “Envenomation from the spines of the caterpillar causes severe pain, burning, swelling, nausea, abdominal distress, and headache. … The best known venomous caterpillar in the American south- west is the puss moth caterpillar, Megalopyge opercularis, commonly called an asp, wooly asp, Italian asp, opossum bug, wooly slug, and el perrito. It is considered one of the most toxic caterpillars in North America.”  We agree with you that the two caterpillars look very similar, and it is entirely possible that some Asp postings on our site are misidentified, and are actually the caterpillars of the Black Waved Flannel Moth.  Regarding the relative venomousness of the two species, we cannot provide you with a scale or data, but we do know that irritation and reactions to stings and bites from insects vary from person to person.  Some folks are highly allergic to the sting of a Honey Bee while other folks are barely affected at all beyond the initial pain of the sting.  Some folks have tremendous reactions to the bite of a Lacewing, while others are not affected at all.  We would urge you to refrain from handling both species, though again, distinguishing between the two might be difficult.  It is also possible that the sting of the Black Waved Flannel Moth caterpillar has not been studied as extensively as has the Asp.  Of the entire Flannel Moth family Megalopygidae, the Auburn Agriculture page on Stinging Caterpillars states:  “Flannel moth caterpillars, like slug caterpillars, do not exactly fit the description of the typical lepidopterous larva. Structurally they differ in having seven pairs of prolegs rather than five (or less) pairs common to typical caterpillars. Most are clothed with fine, long, silky hairs. There are no conspicuous large, threatening, bristle-bearing “horns” to warn of danger; however, concealed within the hairy coats are venomous setae capable of producing severe reactions.”  While the Black Waved Flannel Moth is not discussed in the article, Auburn Agriculture does clearly state:  ”  Puss Caterpillar (Megalopyge opercularis) The puss caterpillar (the adult is called southern flannel moth) is our most ‘dangerous’ stinging caterpillar. Contact may produce severe reactions including: intense burning and nettling of the skin; severe pain; reddening and inflammation; development of pustules and other lesions; numbness; swelling, which may sometimes be extensive; and nausea. Pain may persist from one to twelve or more hours. In some instances, victims have required medical attention. The larva is urticating in all stages, but severity of the reaction is generally proportional to size. Also, newly molted skins retain stinging capabilities.”  There you have it.  According to Auburn Agriculture, the Asp is “our [North American] most ‘dangerous’ stinging caterpillar.”

Subject: supplement photo (dorsal)
Location: Frederericksburg
June 30, 2017 8:19 pm
I have a dorsal view of the moth…better overall….not just the detail….of the Black Waved Flannel Moth photo i sent, to help make an ABSOLUTE identification.
It seems that both the puss variety and this one are all something to avoid. I wanted to know if seeing this moth might indicate puss or super venomous caterpillars in the vicinity. A friend in the southwest once had to go to the ER after leaning on a puss caterpillar.
Subject: Black waved flannel moth
Location: Fredericksburg, Virginia
June 30, 2017 12:46 am
Signature: Susan Warner

Black Waved Flannel Moth

Dear Susan,
Thank you for sending in a supplementary dorsal view of a Black Waved Flannel Moth.

Subject: Caterpillar ID
Location: Northern Virginia
January 5, 2017 7:50 am
Found these in early fall in Northern Virginia. Can’t find a picture of it anywhere. Any idea what it is?
Signature: Chad

White Flannel Moth Caterpillars

Dear Chad,
You should handle these White Flannel Moth Caterpillars,
Norape ovina, with caution because according to BugGuide:  “Caterpillar has stinging spines.”