A few weeks ago, I took my camera across town for a walk in a small local prairie. There were numerous flowers blooming, but the stiff sunflowers (Helianthus pauciflorus) were stealing the show. I shot quite a few photos of them from various angles.
I noticed that a few sunflowers seemed to have their “petals” (technically speaking, they are the ray flowers) folded in toward the center of the flower. I’d seen this quite a few times before, but this time I decided to investigate. I gently pulled the petals apart and found they’d be held down with what appeared to be silk. Beneath them, an insect larva was hiding and, presumably, feeding on pollen or other flower parts.
I’m not expert enough with insect larva identification to know for sure, but I’m guessing the larva is a moth larva – I know at least some of those have the ability to make silk. Some of you reading this will surely know more about them and comment below. (Thanks for your help.)
A few days later, I ran across some similarly closed up flowers in a different prairie. When I opened those up, there was another larva inside, but it was much darker in color. I wonder how many different species have this behavior?
The larva I found was just one of many examples of insects that create safe hiding places for their young to feed in. Spittle bugs and gall-forming insects are two others that are common in prairies. Of course, for every great hiding strategy, there is at least one predator that has developed a counter strategy. I don’t know what eats the petal-tying larvae, but I bet there’s something out there. I’m pretty sure guys-with-cameras are not the only ones who can find them. Fortunately, for the larva I found, I wasn’t hungry at the time.
The Iowa Insects Listserve, or bugguide.net might help you get identification of the caterpillars.
Maybe this table will help you.
I had the same thing happening in my Black -Eyed Susan’s this year. The caterpillars were light green.
I suspected they were White cabbage butterfly larva as I observed several adults laying their eggs on them through the month of August.
Had small wasps come in to investigate. Watched one push her way under several of the folded ray flowers. Did not observe her carry away any larva though.
I’ve seen similar caterpillars in grassland daisies here in Australia. Mostly yellow flowered ones such as Podolepis. Hey you could always mesh bag the flowers and return to see what moth it becomes.
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