This caterpillar from a nearby park with head held low seems resigned to its fate as a parasitoid host. OK, I know that’s a normal position — allow me to anthropomorphise a bit.
You can see some white eggs on its back. I assume a tachinid fly left those, placing them close enough to the head that they couldn’t be removed.
In this next image, you can see there are also some already hatched eggs, sealing this little guy’s doom.
I know tachinid fly larvae have breathing tubes that pierce the host’s skin. Could those long fibers amongst the eggs be those breathing tubes? I wouldn’t think they would be so long. I’m more inclined to think those are just bits of debris that maybe got stuck to whatever holds the eggs in place.