We’ve featured queen butterfly caterpillars before, but each time we observe them, we learn something new.

How many caterpillars do you see on this young rush milkweed plant? Where are they on the plant and what are they doing?

We’ve noticed queen caterpillars often feed on the unopened flower buds. Those are the parts that disappear first.

This photograph has a few extra features. Let’s look more closely.

What’s that shiny white bump at the base of the bud on the top of the stem?

That is a hatched queen butterfly egg. Bonus points if you can find the shed exoskeleton from a previous molt.

The caterpillar in the lower middle of the first photograph of this post has finished off the flower buds. What does it have to eat?

What is the caterpillar doing?

It is crawling out to the tip of what serves as leaves on a rush milkweed.

Now it begins to eat. Any guesses why it might start at the tip?

It doesn’t take long. By the time I’ve taken a few more photographs, the “leaf” is gone.

If you’d like to see the rest of the life cycle, try the queen butterfly emerges post.