Often times, a commen theme of sci-fi are wacky creatures with fully-formed eyes attached to thin stalks. I must ask why are there no vertebrates on this planet that have such eyes? One reason I could think of is that nerve signaling would take a little longer. Another reason I might think is that it is too water-costly. Vertebrates like terrestrial amphibians and mudskippers have such protruded eyes, but when there isn't a lot of water, they close their eyes to conserve the water they have.
Of course, we have stalked eyes on Earth in arthropods and mollusks, but why not vertebrates?
Regards, Isaac.