Marine Institute
SeaRover Dive Video

D535B Transect RB09 Dense Solenosmilia reefs. Steep slope/vertical walls with mixed corals and sponges. Priority. Features: Ridge, Wall, Escarpment, Mound, SAC. Water depth: -1700 m. TL: 1.5 km. SOL: 14° 32.099' W 55° 55.326' N

Highlights: Acesta excavata file shell & Solenosmilia Antipatharian coral & sea fans Sea fan & Anthomastus

The start of this dive has coral rubble and Solenosmilia colonies across rocky hard bottom. Gorgonians are abundant with brisingiids, encrusting sponges, Anthomastus sp., Bathypathes sp. and small glass sponges. This faunal community continued until a steep vertical cliff with some areas populated with of large patches of blue sponge, the stone coral Solenosmilia, the oyster Acesta excavata, (both living and dead), the soft coral Anthomastus sp. and brisingiids. Other areas of the cliff are relatively bare, with Stichopathes species protruding from crevasses in the rock. On the top of cliff, among the rubble, are large numbers of sponges and corals e.g. Jasonisis sp., Solenosmilia and Bathypathes sp. Coral rubble is evident for entire dive.

START VIDEO [00:00:00]/16:36 [1] Solenosmilia variabilis reef (mainly dead) on vertical wall boulder hosting several species of coral and sponge assemblages. First sight of Centrophorus squamosus. Suspended mud present. [00:01:00]-[00:02:00] the ROV moves up and down in the water column following a wiggly direction and it moves slowly for imagery. [00:05:00] the ROV moves uphill. Dominant species Ophiomusa lymani. [00:08:00] [2] Steep muddy bedrock with overhanging S. variabilis. Jasonisis sp. dominates. [00:15:00] The ROV hovers high in the water column to descend on the ground. Accidental mud cloud obscures the camera for a few minutes. The ROV moves in the water column to escape the mud cloud. [00:16:00] Visibility clear again. Muddy bedrock cliff hosting S. variabilis reefs with several species of sponges. [00:26:34]-[00:32:00] ROV stops for imagery, including Jasonisis sp. and S. variabilis zoomed images. [00:34:00] camera is using a dark light. [00:34:40]-[00:35:00] Quick shot of possible Coryphaenoides species eggs/nursery among S. variabilis reef (beneath Jasonisis sp.). [00:36:00]-[00:45:00] ROV stops for imagery and sampling (Porifera encrusting green OTU802). [00:45:00] The ROV hovers high on the ground. [00:47:00] ROV descends on the ground. [00:52:00] Images are dark. [00:54:00] ROV reaches the cliff edge; it changes direction by ~45 to the right and continues to investigate the summit. [00:58:00] Muddy and S. variabilis reef (mainly dead) on a moderate uphill. Mycale lingua is the dominant species. [01:01:00]-[01:16:00] ROV stops for sampling S. variabilis with porifera encrusting yellow OTU58 and Caryophyllia sp. OTU6 (This sample is not recorded in the log book neither in the sample images folder). [01:18:00] ROV zooms in revealing a dense patch of Stichopathes sp. OTU560 on muddy substrata. [01:21:00] Images particularly dark. [01:22:00] Images back to normal. [01:37:00] ROV moves up and down, showing blue water for a few seconds while spotting a C. squamosus just before END VIDEO [01:39:00]/18:15.

Progression Start Duration Code Name
1[00:00:00]00:06:27M.AtLB.Bi.CorRee.SolFraMixed coral assemblage on Atlantic lower bathyal Solenosmilia reef framework (biogenic structure)
2[00:06:28]00:06:28M.AtLB.Ro.MixCor.DisSolDiscrete Solenosmilia variabilis colonies on Atlantic lower bathyal rock and other hard substrata
3[00:12:57]01:26:29M.AtLB.Bi.CorRee.SolFraMixed coral assemblage on Atlantic lower bathyal Solenosmilia reef framework (biogenic structure)

Porifera
cf. Farreidae : 1142 : R
Mycale lingua : 171 : O
Porifera encrusting green : 802 : R
Porifera encrusting sp. 15 (yellow) : 58 : R
Porifera lamellate (Hexactinosida) : 1151 : R
Porifera lamellate sp. 10 : 1010 : R
Porifera lamellate sp. 9 : 606 : R
Porifera massive lobose sp. 22 (yellow cf. Hertwigia sp. ) : 616 : R
Porifera massive lobose sp. 32 : 1090 : R
Blue Porifera encrusting : 800 : R
Porifera vase (cf. Aphrocallistes) : 1162 : R
Cnidaria
Cerianthidae sp. 1 : 2 : R
Actiniaria sp. (large red) : 1120 : R
Actiniaria sp. 20 : 605 : R
Actinernus michaelsarsi : 554 : R
Actinoscyphiidae sp. 1 (pink) : 1047 : R
Actinostolidae sp. 1 : 132 : R
Liponema sp. : 1055 : R
Stichopathes sp. : 560 : R
Bathypathes sp. (brown) : 284 : R
Dendrobathypathes ( prev. Stauropathes sp. 1) : 1015 : R
Parantipathes sp. : 1042 : R

Telopathes sp. 2 (red) : 1181 : R
Caryophyllia sp. 2 : 6 : R
Caryophyllia sp. 5 (bullseye) : 584 : R
Solenosmilia variabilis : 700 : O
Zoanthidea sp. : 1149 : O
Anthomastus grandiflorus : 278 : R
Anthothela grandiflora : 311 : R
Acanella arbuscula : 585 : R
Eknomisis sp. : 649 : R
Keratoisis sp. (fine branching) : 1157 : O
Paramuricea sp. : 1050 : O
Gorgonacea sp. (pink, Solenosmilia assoc.) (Jasonisis) : 1070 : O
Kophobelemnon stelliferum : 442 : R
Hydrozoa (flat branched) : 56 : R
Arthropoda
Caridea (indet.) : 1077 : R
Munidopsis sp. : 1126 : R
Colossendeis sp. 1 : 1059 : R
Mollusca
Acesta excavata : 1062 : R
Graneledone verrucosa : 973 : R
Cirrata sp. (indet.) : 1180 : R
Bivalvia sp. : 9973 : R
Echinodermata

Pentametrocrinus atlanticus : 436 : R
Ophiomusa lymani : 551 : F
Ophiuroidea (indet.) : 1076 : R
Ophiuroidea sp. (orange deep) : 646 : R
Brisingidae sp. : 274 : R
Solaster endeca : 573 : R
Solasteridae sp. : 9978 : R
Pterasteridae sp. : 299 : R
Echinus sp. (deep, white/pink) : 1052 : R
Chordata
Ascidiacea sp. 2 : 20 : R
Centrophorus squamosus : 1048 : R
Chimaera opalescens : 653 : R
Trachyrincus sp. : 446 : R
Macrouridae sp. (cf. Coelorhynchus) : 1172 : R
Phycis blennoides : 1020 : R
Polyacanthonotus rissoanus : 552 : R
Cataetyx laticeps : 1111 : R
Neocyttus helgae : 563 : R
Actinopterygii sp. 3 : 930 : R

Number of species = 62

© Marine Institute, MERC Consultants, Bernard Picton 2022