Sunday, October 3, 2010

American Dagger Moth Caterpillar, Acronicta americana

As I was walking on the Little Miami Trail earlier this week, I saw this fuzzy yellow caterpillar with black tufts hustling across the pavement. I knew what it was right away--a young American Dagger Moth Caterpillar. The early instars of this caterpillar are bright yellow like this one, but the later instars get paler and paler, until they can be almost white. American Dagger Moth caterpillars are so fuzzy, cute and cuddly you just want to pick them up and let them crawl on you...but don't! I know this from experience. When Matty was about 2 years old, we were on the back deck when a big, beautiful white Dagger Moth caterpillar crawled in his path. He let the caterpillar climb up his arm and on his leg, and he was laughing...and loving the little thing, but I wasn't too keen on it, so I walked Matty to a tree and let the caterpillar climb onto a leaf. Good thing I did because wherever those fuzzy little hairs had touched his delicate baby skin a huge red welt appeared. I can't remember if the welts appeared within hours or the next day, but when I took him to the pediatrician, she knew right away what had happened to him. "Has Matty been playing with a fuzzy white or yellow caterpillar?" D'oh! When I got home, I looked up the caterpillar and learned all about him. A week later, an article appeared in the newspaper advising people to beware the cute, fuzzy white caterpillars roaming about. A week too late for us, but we always do tend to learn things the hard way...

A young American Dagger Moth Caterpillar (Acronicta americana) looking dapper in his bright yellow and black bristly hairs (setae).

...he is soft, he is fuzzy, but don't touch! Those silky looking hairs and tufts can leave stinging welts!

The American Dagger Moth caterpillar doesn't sting like a wasp or bee. It doesn't have a stinger at all. The fuzzy hairs (setae) are hollow, and when they touch the skin, they break away releasing toxins from poison glands to which they are attached. (Click here for details on "stinging" caterpillars.)

The toxin-wielding setae make me think of deadly little straws...like something out of James Bond...sort of. It's not like these caterpillars are "attack" caterpillars. They don't release their toxins on purpose. The toxins just spill out when the hair is broken.

...not all species of dagger moths have "stinging" setae or spines, but do you want to risk it? :-) Move along little caterpillar. Hope to see you again some day as a moth!

38 comments:

Roy said...

Interesting! I've seen plenty of these around, but I've never picked any up. Now I'm glad I didn't!

Chris said...

Wow quite an interesting funny looking creatures.... What a funny hear style!!! Good pictures of a funny creature!

Out on the prairie said...

Glad to never have tried one for bait,I seem to react big to insect stings.Sometimes when I trout fish I have tried recent hatch that are around.Nice macro and post.I was on Lake Miami today here in Iowa.

Angela said...

What a fuzzyy little creature.

Laure Ferlita said...

Such a fascinating combination of cute and toxic!

Love the captures even if I don't get to play with the cute little bug!

Montanagirl said...

Wow, I had never heard of such a thing! We obviously don't have them here that I know of. He sure is pretty though.

Abraham Lincoln said...

I like to see these but am half afraid to touch them. I don't know if mother said not to pick them up or not but must have.

Louise said...

Beautiful. I've never seen one around here. I think I'll stick with my woolly bear caterpillars.

Wanda..... said...

Now I know...not to even think of touching these caterpillars!

Nicole MacP said...

Funky looking little critter! Your pics are incredible!

Susan said...

Love that you led Mattie to a tree so the caterpillar could escape (sort of like the Zen of mothering)..I've seen them here too, but never picked one up.

Betsy from Tennessee said...

Well for goodness sakes, I have never seen anything quite like that... Isn't he 'purdy'?????? Glad you saw that one... It's definitely new to me... So pretty!!!!

Thanks, Kelly.
Hugs,
Betsy

Adrienne in Ohio said...

I love seeing these, but I'm always wary, too. I love that when you look at them close up, you notice that their skin is actually bright green. Very colorful!

Busy Bee Suz said...

He is so cute and unusual looking!!!!

Margaret Bednar said...

"Move Along, Little Caterpillar" Sounds like a title of a book. Such an amazing yellow - great photo captures.

dAwN said...

Very interesting..I certainly will remember not to touch that one!

troutbirder said...

Beautiful but dangerous. Interesting post!

Roy said...

It does have that, "Touch me if you dare' look about it Kelly.

Eve said...

Now that my internet is a bit faster I really need to stop here more often Kelly! Your photos are fantastic and paintings just beautiful! Thanks for stopping by my place again!

holdingmoments said...

A real beauty Kelly.

Warren Baker said...

It does look cute though Kelly. :-)

Carol Mattingly said...

Love Love Love this post and photos. Carol

Elaine said...

This guy is new to me. He's very pretty even though he's an untouchable.

Ben and Carrie Tracks said...

love love love caterpillar photos! As wildlife biologists we have really grown to appreciate the art of capturing wildlife via photo- thanks for sharing and excited to have run across your blog to follow :)

Daniel said...

I got stung by one of these in northern Michigan once. It fell onto my tee shirt sleeve from a tree and crawled onto the inside of my elbow without my knowledge. The next time I bent my arm, OUCH! My arm swelled to twice its size and my stomach was covered with hives for about a day. That was an exceptionally severe case, but none the less these things are not to be trifled with.

CuriousAboutNature said...

I saw a pair of these today and wondered what kind of caterpillar. When I tried to pick up the first one it didn't curl like others it actually went into defense mode like it was going to bite me. So I picked it up with a stick and moved it off of the sidewalk so it wouldn't get stepped on...now I'm curious to see what it will look like when it grows up.

RickT said...

One of these guys got in my shirt somehow. My wife got it out, but all day I felt a prickly irritating feeling in my shirt. The next day my back was covered in welts. I have hundreds of them and they are horribly itchy! I would stay away from this cute little guy!!!

Donald Vowell said...

Thank you for making this site i knew they was dangerous but wasn't sure how bad my wife and i live in east Tennessee in blount county and have seen quite a few of them lately

chessiesays said...

Thanks to your photo, was able to identify the caterpillar I saw today on a beach trail in Greenwich, CT.

was not in my guide, Caterpillars of Eastern North America, so my thanks!

did not try to touch, since it looks like this one makes an effort to discourage interference!

chessiesays said...

Thanks to your photo, was able to identify the caterpillar I saw this morning on a beach trail in Greenwich CT. Did not touch, since it looks like this one works hard to discourage interference!

Nicholas Butovich said...

The kids and I saw an American Dagger Moth caterpillar on the sidewalk in Chicago a few days ago.

Nicholas Butovich said...

The kids and I saw an American Dagger Moth caterpillar on a sidewalk in Chicago a few days ago.

Zeebo said...

One of these was crawling on my ankle at a cookout last night. Today it looks like I got 50 mosquito bites where it was. Guess I didn't flick it off in time.

Zeebo said...

One of these was crawling on my ankle at a cookout last night. Today it looks like I got 50 mosquito bites where it was. Guess I didn't flick it off in time.

Zeebo said...

One of these was crawling on my ankle at a cookout last night. Today it looks like I got 50 mosquito bites where it was. Guess I didn't flick it off in time.

Candace Ryberg said...

Saw one of these furry guys on my door frame yesterday, and for some reason I decided just to let it go on it's way after photographing it. I had thought about moving it to a tree, bur decided he would know better how to get to where he wanted to go. Now I'm glad I didn't pick him up! Nature and intuition know best!

Candy Durphey said...

Cute! We learned the hard way when grandpa found this cute little guy and gave it to my 6 and 4 year old. They also ended up with red spots.

Candy Durphey said...

Cute! We learned the hard way when grandpa found this cute little guy and gave it to my 6 and 4 year old. They also ended up with red spots.