This nurse shark is about six feet in length; I squeezed into the small cavern in which it was resting to get this photo, as my friend Erick looks through the opening. The cavern was tucked into a vertical "wall" on the reef, at a depth of about 60 feet. If this were a more aggressive breed of shark I wouldn't have risked being so close-- for this photo my wide-angle lens was only about 1-2 feet from the subject, and my back was bumping into the cavern wall behind me. Identification:  Ginglymostoma cirratum (?)