Name this critter

I spent the afternoon wading thigh-deep in eelgrass beds, and I'm tired, sunburnt, and somewhat wound up. I'll have photos and a report as soon as I finish sorting.

Meanwhile, just a bit of silliness.

Can you identify this ten-legged thing I found? Or take a wild guess?

I've removed the background, because that would make it too easy, since I've already given you a hint.

And that's a second hint.

Third hint: it's about an inch across.

I'll give you a couple of days to come up with ideas, then post the whole photo.