Highlights: 00:30:16 Solenosmilia reef 00:37:10 Sea fan & Solenosmilia 00:42:05 Hexactinellid sponge 00:49:00 Polymastiid sponge on Solenosmilia 01:10:00 Close-up of sea fan

The substrate of the canyon floor (1800 m) is soft sediment with pebbles. Xenophyophores are common here with the occasional sea pen. Towards the side of the canyon the sediment is rippled, sand waves occur at the foot of the canyon wall. A terraced wall begins at 1750 m and contains dense areas of Solenosmilia variabilis; midway up this terrace very large bamboo corals occur. Several species of sea pens are noted throughout the sediment, pebbles and rocks of the terraces. The black coral cf. Parantipathes sp. is frequent on the cliffs and terraces. Brisingids and anemones are present among the stone coral Madrepora oculata; brisingids also occur in clusters on rocks. On a 500 m hard incline, sponges are frequent as are the black coral Stichopathes sp., anemones and the occasional stalked crinoid. Common fish species included grenadier and oreos. Coral species, including the stony corals M. oculata and S. variabilis and black corals are abundant.

START DIVE 05:25 [1] Xenophyophres (Syringammina fragilissima) on mixed gravel/mud sediment. Carbonate protrusion with lamellate sponge (not large enough area to be biotope). 00:27 [2] Area of mixed corals dominated by Chrysogorgiidae sp. with mixed sediment including cobbles and boulders. 00:29 [3] pebbles/gravel and xenophyophores, sometimes sparse. 00:35 Small area with lamellate sponges on cobbles. (not large enough for biotope change) HD VIDEO [00:00:00]/05:46 continued xenophyophores on gravel and pebbles. Pebbles become sparser. [00:02:00] [4] sand sometimes with shell hash/gravel component, with sparse sea pens (species hard to discern as they are small). [00:03:00] sand becomes rippled [00:07:00] sand waves, continued pens. [00:10:00] no more sand waves. [00:15:00] [5] Vertical /sloping rock with light mud veneer and some cobbles boulders, uncoiled Stichopathes sp. (OTU560) dominates, mixed corals/sponges. [00:17:00] [6] Solenosmilia rubble on slope, 100% dead, although rubble associated globose sponges (OTU1051) are plentiful. [00:18:00] [7] vertical rock and shelf with attached mixed corals and living Solenosmilia colonies. ROV traverses left along the crest of the ledge until reaching [00:20:00] cobble/boulder slope then continues uphill. Mosaic of mixed coral assemblages dominated by either Stichopathes sp. (slope/boulders) or discrete Solenosmilia variabilis colonies (especially overhangs). [00:25:00] traverse right along a ledge, [00:30:00] stop for imagery (Keratoisis sp.). [00:34:00] [8] continue forward overledge up slope of S. variabilis reef, ~10% living with associated fauna up to [00:36:00] [9] another series of alternating ledges and cobble/boulder slopes with discrete S. variabilis colonies / Stichopathes sp . dominated mixed corals. [00:42:00]-[00:43:00] stop for imagery (cf Farreidae sp) [00:44:00]-[00:46:00] stop for imagery (Parantipathes sp.). [00:51:00] [10] Xenophyophores on pebbles/mud, some cobbles. [00:54:00] [11] Sparse mixed corals on (denser) pebbles/mud with cobbles and boulders. [00:55:00] [12] again less dense with xenophyophores, [00:58:00] [13] cobbles boulders/ buried ledges/vertical/sloping rock with mixed corals, Stichopathes/Solenosmilia dominated mosaic again. [01:04:00] [14] more sloping Solenosmilia reef, again ~10% living with associated fauna. Some islands of Stichopathes on sloping rock. [01:06:00] [15] mosaic of mixed coral Stichopathes dominated cobbles/boulder areas, and xenophyophore fields on pebbles/mud. [01:09:00]-[01:11:00] stopped for imagery (Keratoisis sp). [01:11:00] [16] mud/sand with scattered pebbles hosting xenophyophores, Pennatula aculeata and Ophiomusa lymani. [01:14:00] [17] richer Solenosmilia reef (10-25% living), mixed corals also associated, globose sponge co- dominates (OTU1051). [01:19:00] [18] sometimes sparse Stichopathes dominated mixed corals on sloping rock with mud/gravel/pebble veneer, cobbles/boulders, vertical rock, and broken sloping rock/carbonate, with some white boulders encountered . [01:24:00] [19] increasing coral rubble on boulder/broken rock slope, with discrete living Solenosmilia colonies. [01:27:00] [20] continues mixed corals on rock mosaicked with Solenosmilia reef 25-50%. [01:40:00] [21] Climb over ridge onto large rich Solenosmilia reef 25-50% living, with many framework associated corals and sponges continuing up a gentle slope until [02:04:00] [22] mud/pebbles and xenophyophores. ROV stops, then END VIDEO [02:05:00]/07:51.