Had trouble ID'ing this at first, b/c it's in a weird family: Cossidae!
mothphotographersgroup.msstate.edu/fast.php?plate=7&s...
bugguide.net/node/view/566434
Tiny insect (larva?) feeding on spores of Tomentella crust fungus growing on underside of Quercus branch
Video here:
https://www.youtube.com/channel/UClvfAu8vOX_54G_nsRMH_Jw
Tiny larvae ( <.5 cm ) inside decayed wood, carrying brown orbs, occasionally depositing them. Is it a frass shield like in some Coleoptera larvae? Are they diptera larvae instead??
Bearing a striking resemblance to a slime mold.