Marine Institute
SeaRover Dive Video

D689 Transect 6 Uniform biotope of gentle/moderate slope with occasional aggregations of echinoids. P1. Water depth: 21182020m. Feature: Slope

Highlights: White echinoids White sea cucumber Cup corals Octocoral polyps Brisingid starfish

Of Note: Occasional dense patches of small white echinoids.

The seafloor was uniformly soft sediment with burrows. Fauna include ophiuroids, holothurians, stalked crinoids, and the occasional sea pen. Anemones including cerianthids and Phelliactis are common, with cup corals occurring frequently. Fish are not common and include eels and grenadiers.

START VIDEO [00:00:00]/11:21. Uniform biotope of gentle/moderate slope with occasional burrows and echinods. [1] [00:01:00] ROV stops for sampling 2 pushcores. [00:10:00] [2] Sparse epifauna including Ophiomusa lymani, Holothuroidea sp. 2, Ceriantharia and Echinus sp. on mud. [00:49:00] [3] Here sea urchin are frequently encountered living on mud. [00:50:00] Here aggregations of sea urchins dominate on soft sediment. Muddy slope continues for the rest of the dive. END VIDEO [01:23:00]/12:45.

Progression Start Duration Code Name
1[00:00:01]23:59:59M.AtUA.Mu.UrcComUrchin dominated community on Atlantic upper abyssal mud
2[00:10:50]00:38:10M.AtUA.MuAtlantic upper abyssal mud
3[00:49:01]00:34:19M.AtUA.Mu.UrcComUrchin dominated community on Atlantic upper abyssal mud

Porifera
Porifera encrusting sp. 1 (white) : 1 : R
Cnidaria
Cerianthidae sp. 1 : 2 : R
cf. Halcampoididae sp. : 984 : R
Adamsia sp. : 1066 : R
Phelliactis sp. 1 : 255 : R
Caryophyllia sp. 2 : 6 : R
Flabellum sp. : 1056 : R
Pennatulacea (indet.) : 1114 : R
Kophobelemnon stelliferum : 442 : R
Pennatula aculeata : 1046 : R
Umbellula sp. : 581 : R

Rhodaliidae sp. 1 : 950 : R
Arthropoda
Chaceon affinis : 254 : R
Paguridae sp. : 205 : R
Eucarida sp. : 1106 : R
Echinodermata
Democrinus sp. : 1103 : R
Ophiomusa lymani : 551 : C
Brisingidae sp. : 274 : R
Zoroaster fulgens : 988 : R
cf. Hymenaster (yellow) : 1174 : R
Echinidae sp. (white) : 559 : C
Phormosoma placenta : 555 : F

Benthogone sp. : 432 : C
Chordata
Synaphobranchus kaupii : 440 : R
Ipnopidae sp. : 1078 : R
Hoplostethus atlantica : 651 : R
Coryphaenoides rupestris : 566 : R
Antimora sp. : 1301 : R

Number of species = 28

© Marine Institute, MERC Consultants, Bernard Picton 2022