Ommatokoita elongata

Also known as Greenland Shark Eye Parasite

Adult females of this parasitic copepod anchor permanently into the corneal tissue of Arctic sleeper sharks, dangling conspicuously from the host's eyes. Their deep tissue attachment causes severe keratitis and extensive corneal scarring, rendering many mature sharks functionally blind. Because these slow-moving deep-sea hosts rely overwhelmingly on acute olfactory and mechanical cues in dark polar waters, the ocular infection appears to cause minimal disruption to their survival.