no hermit crabs dontsleep with their eyes open
crabs have eyes on stalks :)
Yes they can
The stalk of the crabs eyes if cut off or got eaten, the crab is able to grow one back same to the crab's eyes.
hermit crabs can have up to 6 eyes
Their eyes are on stalks and the crabs can move them independently.
Well it is really their eyes.
Fiddler crabs have clear scales over their eyes, but they do not have eye lids that move like we do.
To an extent, yes, it depends on the species of crab Dungeoness crabs, and blue crabs (The most common in seafood resturaunts) have bristle like things around the edge of the sockets that brushes the debris from the eyes. Land crabs like Patriot crabs and ghost crabs have foldable "Mouth Hands" that are basically like little windshield wipers. The exeption to the land crabs is the Halloween Crab which have eye mor similar to Dungeoness crabs. Hermit crabs and subsequently crabs with similar front structure like Japanese spider crabs can fold their eyes down and also have "Mouth Hands" although all crabs have a thin, nearly invisible, coat of skin covering their eyes if you wish to see it I suggest looking for molted crab skins on the beach. Hope this helped!
Of Course they do they have black balls on top of there head those are eyes.
Antennea's they are on stalks, like a bugs.
Horse shoe crabs have a total of 10 eyes, which are spread across their bodies. They have two compound eyes on their front shell for detecting light and movement, and several simple eyes on their body and tail for detecting motion and orientation.