I didn't know lamprey's could grow that large. I've seen them in various documentaries before, but they always were smaller, attached to fish, sharks, ect. What's he feed on, a whale? Lol. Also, it does look like the worm from Prometheus (though it'd actually be the reverse as lamprey's have been around longer, heh).
The other pic is misleading. Those are called camel spiders, which are solpugids. Anyway, that pic was taken really close up making them look much larger than they are. When I saw that pic a few years ago I looked it up. Still doesn't stop them from being ugly up close. Google them, and take a look at close shots of their hairy faces. Now I just have this nice, comfy thread of death, and horror to bring the freaky things, and information to me.