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The bug of the week is a tiny beauty with an attitude. When I first spotted this bug I thought she might be an ant.

bethylidae wasp

But then I looked again. This insect was just not acting like an ant.  She was climbing around on a plant like she was searching for prey, more like a wasp.

bethylidae wasp bethylidae wasp

She doesn’t look quite like an ant either. Her antennae are not elbowed like an ant’s would be. Bug Guide has some pictures of bethylid wasps that look fairly similar to this one, although I couldn’t find an exact match.

Edit: I guess first impressions were best. Seems this is a Pseudomyrmex ant. Check this photograph of Pseudomyrmex pallidus. Thanks to Cameron for straightening me out.

Bethylid wasps are parasites* of caterpillars and beetles larvae. Even the small ones like this have a potent sting. They use their stingers to immobilize the host larva, and then lay their eggs on it. The wasp larvae that hatch from the eggs use the caterpillar or beetle grub for food. Because the hosts are often pests of crops, these bethylid wasps are considered to be beneficial insects. Just leave them alone if you are lucky enough to see one.

*A parasite uses one host that is bigger than itself for food. A predator catches and eats many smaller prey items for food.

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We were doing a bit of yard work when we came across this leaf-footed bug. These insects get their name from the leaf-like flanges on their hind legs.

leaf-footed bug

Note the light-colored zig-zag marking across the middle of its back.

Leaf-footed bugs have sucking mouthparts and sometimes feed of fruit such as cactus fruit, oranges or peaches. Although we do have citrus, I think this one is a visitor from our neighbors’ yard. Our neighbors have a pomegranate bush. Pomegranates are one of the leaf-footed bugs' favorite foods.

Like many of their relatives, these true bugs can give off an odor when handled.

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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