In this macro view of the reef, a triplefin stares at the camera as it rests on a pair of blue tunicates. The near tunicate has its sphincters constricted, inhibiting the flow of water-- a typical reaction if the animal is disturbed, even if only by the passing of a shadow. At left are a translucent species of tunicate with dark spots, along with a green-colored species (note the constriction of the small siphons). Tunicates, also known as sea squirts, have a nerve cord, making them the invertebrates most closely related to the vertebrates. They are often confused with sponges, but are unrelated. |
Identification: |
Rhopalaea sp. (blue tunicates) |
Atriolum robustum (green tunicates) | |
Clavelina moluccensis (clear tunicates with spots) |