I have seen this giant bloody caterpillar since I was a kid but I don’t know what it is. And I can see them being stepped to death almost everyday. I just have to know this insect.

It’s called goat moth.

Goat moth caterpillar This image is taken by Wikimedia user BabelStone.

Three fun facts about goat moth: the first is they get the name because the larva smells like goat, I dare not verify this. The second is they may live up to five years inside a tree before get to the ground and pupate. Since they eat wood which doesn’t contain much nutrition, no wonder they grow so slow. The third is even though adult moths can’t feed, they can sense tree sap. The reason is damaged bark is easier for their kids(larvae) to penetrate.

They are regarded as pest since they can kill a tree in several years. I highly suspect those old willow trees beside the road are chopped down because goat moths empty the trunk thus endanger the pedestrians.

Why there are so many British websites in the search results of this moth?