The parasite Ommatokoita elongata probably made a few of you squeamish. If so, then you probably want to just close this page, too. Caligus oculicola is a recently described species of copepod that lives on the surface of the eye of tiger sharks (Galeocerdo cuvier). Although most species of Caligus infect teleost (bony) fish, not sharks, this copepod seems to have found an ideal habitat of the eyes. They have specialized structures that allow them to adhere, suction-cup style, to the eye and then they proceed to feed on the host's tissue through a scraping and swallowing kind of fashion.
Drawing of a male Caligus oculicola, modified from the original paper.
Thanks to Laurence Frabotta and Colleen Ingram for nominating this parasite.