Optic mustard fungus

Found this growing on a loblolly pine stump yesterday:

In the morning it was brighter, sort of a cross between tennis-ball yellow and yellow ochre, and smoother in texture. By late afternoon, when I got around to borrowing my wife’s camera with the good macro lens, it was spongier and less obnoxiously colored. As dry as it’s been lately this hasn’t so far been a good summer for fungus, but this is a new one on me.