Thursday, September 15, 2011

Goldenrod Soldier Beetle

Towards the end of summer, it’s not unusual to find an abundance of insects visiting the blooms of the many late season prairie flowers. Sometimes a single insect species will become so numerous that you find one in every flower you examine. That’s the case this year with the Goldenrod Soldier Beetle, Chauliognathus pensylvanicus. Here’s one visiting a Western Sunflower.

You’ll certainly find this beetle on its namesake goldenrod, but it’s definitely not limited to that one genus. I’m seeing Goldenrod Soldier Beetles on about every flower across the prairie, but they seem to have a decided preference for those of the Aster family, what my generation always called the composites.

These beetles are quite animated and are certainly entertaining to watch. They tend to stay still only when they’re eating and even then it’s only a few seconds at a time. They always seem to be on watch, cocking their heads back and forth as though scanning the surrounding area for trouble. The fact that I got so many close-up shots of them suggests that they don’t perceive me as a great threat. This one has paused atop a White Snakeroot to take a quick look around.

They feed on pollen and nectar. Flowers of the Tall Boneset are a particular favorite.

Of course, anything that wades around in flowers can also serve as a pollinator. The beetle feeding on this Wingstem has collected pollen on about every part of its body. The legs appear to be carrying the greatest load. The black and yellow coloring of the Goldenrod Soldier Beetle, especially the striping on the abdomen, makes me think that that there’s a little wasp mimicry going on here.

There were also many couples working to ensure a large crop of beetles for next year. Eggs are laid on the ground and the larvae spend their time in the organic layer on the soil surface.

This pair doesn’t seem content to stay on the Blazing Star. They seem transfixed by the Ashy Sunflower just out of reach. Reminds me of so many young married couples dreaming of things they can’t yet have.


  1. That's not the beetle I was looking for.

  2. Replies
    1. Thank you so much for the picture of this bug. I have looked and looked to find out what this bug is called. There are lots of them and I will be glad when they are gone. It has been such a problem to keep them out of my swimming pool. I guess the high winds here in South Texas knock them out of the air. This is the first year I have ever seen them.

    2. Thank you for your picture of this bug. I have looked and looked to find out what it is. I have so many of them that keep falling into my swimming pool. I really hate them. Maybe the strong winds were are having is causing them to fall out of the air. I cannot wait until they are gone. I surely do not need them.

  3. Hi Linda. Glad I could help. I hope your beetle problem clears up soon.