I raised over a dozen luna moths late last fall, and they overwintered. Three have emerged, and the two females were visited by males early in the night, but didn't leave me any spill-over eggs.
The other day, I found a cocoon on an old magnolia leaf, one of those leaves that will likely be shed this year, once the new growth has fully formed. At first I assumed it was a luna moth, since that's mostly what I see here. But after looking at the color, I thought it might be a polyphemus moth. I pulled the silk off the leaf and laid it in the cage with the home-raised lunas and noticed that it was considerably heavier than the luna moth cocoons. Also, this one has what might have been a 'bag' when it was spun, but was dessicated over the winter. Could the long straight thing at the top have been the top of the cecropia 'bag'? I would be happy to see a polyphemus moth, not having seen one in a while, but I'd completely flip over a cecropia - they're EXTREMELY rare here.
Anyway, this picture shows the luna cocoon on the right, and the mystery cocoon on the left -
It might be that the color difference comes from the fact that this one was outside, instead of in the cage on my porch, not being affected by rain. But on this rainy day I'm wondering about it.
Anybody have any ideas as to the ID of the the cocoon on the left?