When I noticed the beetle there was something else on the leaf, I figured it was another insect. Then I looked for a yellow Tortoise Beetle on the internet but the black spotted yellow tortoise beetle looked quite different. It's shell was more clear and antennae and legs were mostly yellow not black. I found out Tortoise beetle larvae are prickly - then I figured it out - I think!
The picture shows both the shell from the Argus Tortoise Beetle pupa and the newly morphed beetle - you can see the impression of the shell on the white membrane material and the spines are now facing the leaf.
I do have several pictures showing orange colored Argus Tortoise Beetle from the same area. Could exposure to the sun or eating milkweed cause it to darken to orange?

The last picture shows the hours old shiny and slick new Argus Tortoise Beetle. It is probably only yellow because it is newly hatched and will darken into a bright orange color later.