A week ago we found a very distinctive caterpillar that we were confident
could be identified immediately.  Alas we are stumped.  Hope someone out
there can help.  It was found on flat topped white aster and has been
consumming such.

It is black with full body length strips starting with red at the feet,
then yellow, then 3 thin blue strips with a yellow to orange strip down the
middle of the back.  That middle strip has since turned to gray/violet.  It
is not hairy.

It is pupating into a green cocoon ? chrysalis?    Any ideas?   Can anyone
suggest a good caterpillar reference?

Thanks,  Ruth

E. Dorset, VT