Representative images of the biotic zones on the Tasmanian seamounts.

a. Hormathiid-dominated volcanic rock, at 2400 m. The rubble surrounding the rock is predominantly shell plates of deep-sea barnacles. Live barnacles are visible as white objects amongst the greenish-brown anemones, and to the left, a branching Isidid colony. For scale, the anemones are about 5 cm in diameter. b. Reef-scape at 2600 m, showing the dominance of live and recently dead (white skeletons) gorgonians, most apparently in the genus Isidella. Hormathiids (greenish brown) and barnacles (white) are visible on the rock, along with a glass sponge (Hexactinellid) to the left. Note the hormathiids attached to the up-right dead coral skeletons. c. Deep barren volcanic rock at 2820 m. The laser points are 10 cm apart. d. Interface between deep rock and sand plain at 3990 m. All photos were taken on Jason dive 392.