Currently viewing the category: "Leaf Skeletonizers"
What's That Bug? does not endorse extermination

Beautiful Blue Bug
Sun, May 10, 2009 at 1:44 PM
These blue fellows showed up in late April, proceeded to make a love shack of my grapevines, and disappeared shortly after. A couple of weeks later my vines are covered with these cute, little yellow and black caterpillars. I’m assuming the two are related but I can’t seem to find them on any of the internet searches I’ve done.
Thanks for any info, Rebecca
Mesa, AZ

Western Grape Leaf Skeletonizer

Western Grape Leaf Skeletonizer

Hi Rebecca,
We are so happy to have your photos of the adult moth as well as caterpillars of the Western Grape Leaf Skeletonizer, Harrisina metallica , in the same letter.  According to BugGuide it is:  “Native to southwestern USA and northern Mexico. Occurs from California to Texas, north to Colorado and Utah ” and “Larvae are a severe pest in some California vineyards.”  A very similar species, the Grape Leaf Skeletonizer, Harrisina americana, is found in the eastern U.S.

Western Grape Leaf Skeletonizer Caterpillars

Western Grape Leaf Skeletonizer Caterpillars

What's That Bug? does not endorse extermination

little worms on grapevine
I think you guys are great. I would love to know what these little worms are. They really don’t seem to move, but I’ve found evidence that they’ve been around. Where did they come from and do they need to be destroyed or do they turn into something good? I found them on my grapevine. Thanks,
Lois Cain

Lois
These caterpillars are Grape Leaf Skeletonizers, Harrisina metallica. The caterpillars are a major defoliator on grape vines.

What's That Bug? does not endorse extermination

Whats this?
Hy, I am Don from Franklin, La, and I have a second year growth of Thompson White Seedless grape vines that have and still has this pocket of caterpillars, they start with a group of egg pockets cluster about the size of a quarter and grow to small caterpillars and eat away at the leaves, I sprayed with daconil and also use seven dust (which is better) than daconil. What is it and what is the best control? I also saw a leafhopper.
Don

Hi Don,
These are Grapeleaf Skeletonizers, Harrisina americana. The caterpillars will eat the leaves to the veins. We don’t provide extermination advice.

What's That Bug? does not endorse extermination

caterpiller
WTB, you guys are wonderfull. I had a question about an Orange Dog a while back @ you guys got back to me right-a-way. Thank-you. I have another Caterpiller I’m curious about. I didn’t see any other pictures of them, so hopefully you’ll get this one I’m sending. (Computer illiterate) I live in Chandler, AZ. ( Phoenix area). Our neighbors have some grape vines growing over our fence. I was very excited that we were going to have fresh grapes until I noticed they were covered by these yellow, black & blue stripped caterpillars. They don’t really seem to be eating the grapes, just the leaves. The plant does seem to be dying however, I don’t know if its from these little guys or just neglect. The one I took a picture of is one of the larger ones. About a 1/2 in. Any-way, what are they? Will they go for any of our other plants, for example, our orange tree? Are they poisonous if eaten by our dogs? Could they be killing the grape vines, & should I be concerned about them? Thanks again,
Cindy

Hi again Cindy,
We have been away and are just catching up on letters. This caterpillar is a Western Grape Leaf Skeletonizer, Harrisina brillians. This is a new caterpillar for our site. They are a major defoliating pest of grapes and will not spread to your other trees. If they are numerous, they will completly strip a vineyard of leaves. This will not kill the vines, but it will not be a good year for grapes. They will not poison your pets.

What's That Bug? does not endorse extermination