I think that is a camouflaged cocoon of a moth species, but not of Psychidae which have a clear axis of cylindrical or conical symmetry, nor Butterflies which have a naked pupa, nor many moth families which have naked cocoon (eg. Limacodidae) or attach it smoothly to a stem (Nolidae) nor bury it underground (eg. Geometridae) or between leaves of the foodplant (eg. Lasiocampidae).
Don the only three things I can add are: 1. It was proximate to fresh herbivory on a leaf but I did not actually see it feeding. 2. There were several on the same small euc. 3. It was mobile.