D538 Transect RB15 Very diverse. Mixed sediment with sponges and coral gardens on hard substrate and xenophyophores on mud. Non Priority. Features: Escarpment, Mound, SAC. Water depth: -1150 m. TL: 4 km SOL: 14° 51.899' W 55° 42.829' N
Highlights: ROV collects bamboo coral - Acanella Antipatharian coral & chirostylids Antipatharian coral - Leiopathes?
Dive begins on soft sediment with some coral gravel. Acanella sp., cup corals and occasional cerianthids are present. Rocks hosting encrusting and lamellate sponges and xenophyophores become abundant where soft sediment occurs. The ground transitions to stony reef where black corals, including Leiopathes sp., Phanopathes sp., Dendrobathypathes sp. and Stichopathes sp. are frequent. Exposed bed rock contains black corals, anemones, glass sponges including Venus flower basket Euplectella aspergillum. A final transition to soft sediment with pebbles with encrusting sponges and urchins occurs. Two large boulders with Leiopathes sp. and black plastic rubbish are observed at end of transect.
START VIDEO [00:00:00]/10:03 [1] Gravel/sand/mud substrate with dominant Ceriantharia OTU1069 on moderate slope. Suspended sediment. [00:00:00]-[00:06:00] 1 pushcore sampling. [00:18:00]; [00:52:00] Centrophorus squamosus. [00:23:00] [2] Boulders, gravel and mud. Porifera co-dominate with Leiopathes sp. on hard substrata; Ceriantharia sp. OTU1069 dominates mud/gravel sediment. Throughout the transect, a variety of Porifera and Actinopterygii are encountered. [00:42:00] Bedrock, boulders with mud sediment. Porifera (mainly Porifera lamellate Hexactinosida) dominates. [00:51:00] [3] Bedrock, pebbles, mud sediment. Caryophyllia sp. dominate on mud/gravel; porifera lamellate Hexactinosida and Phekallia ventilabrum OTU202 co-dominate on pebbles and bedrock. [11:00:00] Now is bedrock and mud on steep slope with frequent cobbles and boulders. [01:20:00] Now no boulders, instead mixed sediment (mud, gravel). [01:23:00] [4] bedrock again intersperse with mud and gravel. Leiopathes sp. is dominant species. [01:28:00] [5] No bedrock recorded here, mud and gravel takes its place again with Xenophyophora (Syringammina fragilissima) abundant in this part of the transect. [01:50:00] ROV stops for imagery. [01:52:00] ROV leaves the bottom. END VIDEO [01:53:00]/11:56.
Progression | Start | Duration | Code | Name |
---|---|---|---|---|
1 | [00:00:00] | 00:24:41 | M.AtMB.Mx | Atlantic mid bathyal mixed sediment |
2 | [00:24:42] | 00:30:28 | M.AtMB.Ro.MixCor | Mixed cold water coral community on Atlantic mid bathyal rock and other hard substrata |
3 | [00:55:11] | 00:29:42 | M.AtMB.Ro | Atlantic mid bathyal rock and other hard substrata |
4 | [01:24:54] | 00:07:55 | M.AtMB.Ro.MixCor | Mixed cold water coral community on Atlantic mid bathyal rock and other hard substrata |
5 | [01:32:50] | 00:21:02 | M.AtMB.Ro.MixCor | Mixed cold water coral community on Atlantic mid bathyal rock and other hard substrata |
Foraminifera
Syringammina fragilissima : 261 : R
Porifera
Hyalonema sp. 1 : 917 : R
cf. Pheronema sp. (Rock possibly Aphorme horrida) : 1084 : R
Asconema sp. : 1038 : R
Asconema sp. (Porifera massive globose 14) : 650 : R
Aphrocallistes beatrix : 264 : R
cf. Phakellia ventilabrum : 202 : R
cf. Geodia baretti (Porifera massive globose sp. 11) : 601 : R
Porifera cylindrical sp. 2 : 1075 : R
Porifera encrusting sp. 1 (white) : 1 : R
Porifera encrusting sp. 15 (yellow) : 58 : R
Porifera lamellate (Hexactinosida) : 1151 : O
Porifera massive lobose sp. 18 (cf. Farrea sp. ) : 576 : R
Blue Porifera encrusting : 800 : R
Porifera vase (cf. Aphrocallistes) : 1162 : R
Cnidaria
Cerianthidae sp. 1 : 2 : R
Actiniaria sp. 18 : 582 : R
Actiniaria sp. 20 : 605 : R
Actiniaria sp. 30 : 1099 : R
Bolocera tuediae : 12 : R
Actinoscyphiidae sp. 1 (pink) : 1047 : R
Antipathes dichotoma : 1187 : R
Stichopathes cf. gravieri : 283 : R
Phanopathes sp. 1 : 330 : R
Chrysopathes sp. Trissopathes sp. : 540 : R
Leiopathes sp. : 305 : R
Bathypathes sp. (brown) : 284 : R
Bathypathes sp. 1 : 328 : R
Dendrobathypathes ( prev. Stauropathes sp. 1) : 1015 : R
Parantipathes sp. : 1042 : R
Caryophyllia sp. 2 : 6 : R
Caryophyllia sp. 5 (bullseye) : 584 : R
Lophelia pertusa : 250 : R
Madrepora oculata : 251 : R
Zoanthidea sp. : 1149 : R
Acanthogorgia cf. armata : 608 : R
Pseudoanthomastus sp. : 1080 : R
Pseudoanthomastus sp. : 1080 : R
Chrysogorgidae sp. 1 : 1008 : R
cf. Clavulariidae sp. : 289 : R
Acanella arbuscula : 585 : R
Acanella arbuscula (firtree) : 991 : R
Gersemia sp. 3 : 1022 : R
Pennatula aculeata : 1046 : R
Umbellula sp. : 581 : R
Annelida
Bonellia viridis : 267 : R
Serpulidae sp. 1 : 106 : O
Arthropoda
Munida tenuimana : 339 : R
Caridea (indet.) : 1077 : R
Cirripedia sp. 1 : 82 : R
Mollusca
Graneledone verrucosa : 973 : R
Echinodermata
Pentametrocrinus atlanticus : 436 : R
Crinoidea sp. : 1072 : R
Crinoidea sp. 1 : 131 : R
Ophiuroidea (indet.) : 1076 : O
Ophiuroidea sp. 7 - yellow : 340 : R
Brisingidae sp. : 274 : R
cf. Henricia sp. (deep) : 1154 : R
Ceramaster/Peltaster/Plinthaster sp. 1 : 234 : R
Solaster endeca : 573 : R
Solasteridae sp. (white) : 9977 : R
Pterasteridae sp. : 299 : R
Velatida sp. 1 : 199 : R
Asteroidea cf. sp. inulosida : 1186 : R
cf. Echinus (deep pink spine) : 1129 : R
Cidaris cidaris : 211 : R
Hygrosoma sp. : 1125 : R
Echinothuroidea sp. : 1094 : R
cf. Psolus sp. : 1049 : R
cf. Amperima sp. : 628 : R
Holothuroidea sp. (pink deep) : 1179 : R
Chordata
Ascidiacea sp. 2 : 20 : R
Galeus melastomus : 1005 : R
Rajiformes sp. 1 (Neoraja caerulea?) : 652 : R
Centrophorus squamosus : 1048 : R
Hydrolagus cf. mirabilis : 1024 : R
Chimaera opalescens : 653 : R
Synaphobranchus kaupii : 440 : R
Molva dypterygia : 245 : R
Coryphaenoides guentheri : 577 : R
Trachyrincus sp. : 446 : R
Macrouridae sp. (cf. Coelorhynchus) : 1172 : R
Lepidion cf. guentheri : 1160 : R
Mora moro : 349 : R
Cottunculus microps : 128 : R
Neocyttus helgae : 563 : R
Actinopterygii sp. 3 : 930 : R
Number of species = 87
© Marine Institute, MERC Consultants, Bernard Picton 2022