What White-lined Sphinx Caterpillars Eat

I was asked a question last week about what white-lined sphinx moth caterpillars eat. I had read that they eat wild relatives of the four-o’clock, a garden plant. A few weeks ago we visited Boyce Thompson Arboretum State Park and I got some great first-hand information about what kind of plants the caterpillars feed on.

At the arboretum we found caterpillars on a native plant that is being used as a landscape perennial called pink guara (Guara lindeimeri). I noticed, however, the caterpillars were only eating the flowers. Often the flowers lack toxins or feeding deterrents found in the leaves or stems, although I don’t know for sure this is the case here.

whitelined sphinx moth

Some of the caterpillars were working on a plant called white ratany (Krameria grayi).

whitelined sphinx moth

whitelined sphinx moth

I needed a friend’s help to identify that one. The plant has pretty purplish-pink flowers, but they are inconspicuous. She said the plant is a partial parasite that takes food from the roots of fellow desert plants like bursage or creosote bush. I also found out that the flowers produce an oily substance rather than nectar (weird!), but that some native bees will take it to mix with pollen.

whitelined sphinx moth

Finally, we cheered the caterpillars when we found this batch eating the noxious weed, spotted spurge. Go white-lined caterpillars, go! (Sorry, the photo isn’t all that great).

For more information about white-lined sphinx moths and their caterpillars, check these previous posts:

Raising Caterpillars, which also has a photo of the adult

More About White-lined Sphinx Moth Caterpillars

Bug of the Week:  White-lined Sphinx Caterpillars


  1. SuicidalBunny00

    Hello, I know this post is pretty old, but if you’re still around, I have some questions regarding Hyles Lineata.

    I have 4 of these in my backyard, the larval plant is a Jalepeno shrub. But they’re all so hungry all the time, they’re destroying my plants/peppers!! >_<

    Is there any way I can raise them away from the plant? Two of them are ~3"-3.5" (mature), the other two ~.75"-1" (immature). I'm not sure if, because they get so big, do I need to keep them in a giant container? I tried to use a pickle jar, but one of them died, and they didn't seem to like it at all.

    Get back to me via Email – (genevamueller@gmail.com), if you find this soon. Thanks,

    – G

  2. Bruce Bohl

    I have just removed two groups of these caterpillars from my Black Oak…they were devouring the leaves down to the veins….DEFINITELY green with yellowish stripes and a orange-ish mark on or near or the head. Is this feeding typical? I thought they were gypsy moth cats….but after close inspection DEFINITELY Hummingbird. Are they know to decimate an entire tree? They were in the lower branches, none seen higher…tree is 40 foot tall….40-50 years old….I know, I had it planted from the nursery. Please advise on any prevent measures and what my odds are for the future……

  3. Roberta

    Check this page to see if they are waved sphinx caterpillars; https://www.butterfliesandmoths.org/species/Ceratomia-undulosa?page=2

    If they are, they are fairly rare and aren’t likely to cause harm. Caterpillars that feed later in the year do much less damage because the trees are going to lose their leaves soon anyway. Also, most of these native caterpillars have natural enemies that keep them in check.

  4. Susan goody

    What do they eat that is around Mendon UT? I didn’t understand what exactly they eat. I have 3 that I am trying to raise, any tips on how to raise them right and what to feed them?

  5. Roberta

    Where were the caterpillars when you found them? Were they on or near a plant? Those would be the ones to try feeding them first. Plants in the primrose (example photo) and purslane families (an example photo) are known to be favorites, so see if there are any of those nearby. They also eat grape or apple leaves in a pinch.

    If the caterpillars are roughly three inches long they are likely full grown and looking for a place to pupate. Prepare a container with a few inches of moist soil (about the dampness of a wrung out sponge). Add caterpillars and some samples of plants from near where you found them. If they are hungry, they will likely eat at least one kind of plant. If they are ready to pupate, they will ignore the food and dig into the soil. Check the raising caterpillars post and comments for much more information http://blog.growingwithscience.com/2008/09/raising-caterpillars/

    Good luck!

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