It’s a saddleback catapillar. The thorns have venom. Felt it on my neck. Never seen one before, but will definitely be on the lookout from now on.
Have been stung by a caterpillar, of all things, in my neck when I was young. It was mildly interesting that the affected area was more or less the pill-like oval shape of the caterpillar. Wasn’t too bad but I remember it itched like crazy.