Pagurus hirsutiusculus The Hairy Hermit!
It was the kind I took pictures of before. It says in the book, that the Hairy Hermit Crab is "very agile and likes to occupy small, light shells which, especially in adult males, do not completely cover the abdomen." I know a few of you asked about that. I suppose it's a normal thing for these guys. They are like the sprinters of the hermit crab olympics. It also says that they are parasitized by hermit barnacles and bopyrid isopods. I am wondering if having a tiny shell makes them an easier target? Probably.