Highlights: 00:11:29 Black sea urchins 00:19:34 Echiuran worm - Bonellia viridis 00:25:51 Soft coral - Drifa and hydrocoral 00:35:57 Chimaera 00:42:29 Lophelia, sea urchin Cidaris cidaris & cerianthid anemones

This transect occurs along a series of mounds. The substrate varies moving over the mound from sand with pebble and stones at the base to carbonate sediment, terraces and cliffs. The density of stony corals increases from small single clumps to large dense patches, with occasional coral rubble. Both Lophelia pertusa and Madrepora oculata are present, and in some areas both the orange and white morphologies are seen together. Where these coral areas are less dense cerianthids occur in between the clumps.

Throughout this site the fish Lepidion eques, the echinoids cf. Calveriosoma fenestratum and Cidaris cidaris are common, with both C. cidaris and black cerianthids present in very dense patches on occasion. Other species include the hydroid coral Pliobothrus symmetricus, the black corals (Bathypathes sp., Parantipathes sp. and Stichopathes sp.) echiurans and the ophiuroid Gorgonocephalus sp.

START VIDEO [00:00:00]/ 21:28pm [1] The transect starts on a moderate slope of coarse sediment with occasional cobbles and boulders and many Hairtail (Trichiurus lepturus) being encountered. [00:06:00] [2] For the next hour two biotopes dominate although the sediment types vary. Discrete coral colonies occupy cobbles and boulders, and sometimes protruding terraced carbonate rock.

Madrepora oculata dominates, but Lophelia pertusa occurs too along with occasional other corals. The coarse sediment, of sand and gravel or coral gravel, forms a thin veneer over the carbonate rock slope between the hard substrate areas/ terrace step features, and mainly hosts (in varying densities) cerianthid anemones, Cidaris cidaris urchins, and Bonellia viridis echiuran worms. [01:01:00] [3] A carbonate terrace gives rise to a Lophelia pertusa reef which the ROV climbs up and over. [01:02:00] [4] Behind (and below) the reef returns to the previous mosaicked landscape of coarse substrate with discrete coral colonies on cobbles/boulders/carbonate. [01:08:00] [5] after climbing a small cliff of carbonate with a couple of holes eroded into it, the next terrace again hosts Lophelia pertusa reef, although sparser than before then at [01:09:00] [6] returns back to a gently undulating landscape of coarse sediment and discrete colonies on cobbles/boulders. [01:15:00] [7] the landscape levels off to a large area of sand with sparse fauna (mainly the echinothurid urchin Araeosoma fenestratum) and occasional pebbles [01:19:00] [8] but again this returns to varying substrates (coarse coral gravel/sand sediment veneered steep carbonate, or cobbles/boulders on coarse coral gravel/sand sediment) hosting the dominant biotope mosaic. END VIDEO [01:41:00]/23:10