Southern Emerald Moth caterpillar

I was looking at lots of wasps and dragonflies in this field when this tiny guy caught my eye. It looks like a clump of dry leaf or wilted flower, but was "inchworming" its way up the stem of a Bidens alba (Spanish Needles or Common Beggar's Tick.) As you can see this member of the Inchworms (Geometrid Moths) covers its body with bits of plant material to achieve a superb camouflage. It stopped moving when it noticing me taking pictures and would not move even when pushed a little. In the last pic, you can see the pieces of petals and seeds on it, and the tip of my index finger for an idea of size.