Marine Institute
SeaRover Dive Video

D657 Transect 46 Muddy slope with sparse and scares epifauna, including white sea cucumbers and cerianthids. P1. Water depth: 1516m-1537m. Feature: Downhill slope.

Highlights: Sea pen Chimaera & white sea cucumbers Purple sea urchin Hexactinellid sponge - Hyalonema

Of note: Abundant and diverse fish species.

The seafloor consists of soft muddy bottom with many burrows and varying morphology, on a gentle slope. There is very little marine snow and limited current. Epifauna is scarce and consists mainly of cerianthids and very small sea pens (possibly Anthoptilium). Fish species included eels, grenadiers, a Bathypterios sp. and a chimerid. An enormous stalked hexactinellid (Hyalonema like), the head of which was at least 30 cm across was observed.

START VIDEO [00:00:00]/19:49. Muddy slope with sparse epifauna, including sea cucumbers and cerianthids. [1] The entire dive is located on muddy slope with sparse epifauna, including sea cucumbers and cerianthids. [00:01:00] ROV stops for sampling two pushcores. [01:22:00] ROV stops for imagery of Hyalonema sp 1. [01:26:00] Some animals tracks and burrows at this point on the seafloor. Burrows appear to be frequent in this section of the dive. END VIDEO [01:42:00]/21:28.

Progression Start Duration Code Name

Foraminifera
Syringammina fragilissima : 261 : R
Porifera
Hyalonema sp. 1 : 917 : R
Cnidaria
Cerianthidae sp. 1 : 2 : R
Cerianthidae sp. 1 : 2 : R
Actiniaria sp. (large red) : 1120 : O
Actiniaria sp. 20 : 605 : R
Adamsia sp. : 1066 : R
Caryophyllia sp. 5 (bullseye) : 584 : R
Flabellum sp. : 1056 : R
Epizoanthus sp. 1 (Paguridae associated) : 317 : R
Anthothela grandiflora : 311 : R

Kophobelemnon stelliferum : 442 : R
Arthropoda
Paguridae sp. : 205 : R
Mollusca
Hypsogastropoda sp. : 621 : R
Echinodermata
Crinoidea sp. 1 : 131 : R
Zoroaster fulgens : 988 : R
Pterasteridae sp. : 1115 : R
Echinothuroidea sp. : 1094 : R
Benthogone sp. : 432 : F
Chordata
Galeus melastomus : 1005 : R
Galeus sp. : 1305 : R

Chimaera monstrosa : 265 : R
Harriotta raleighana : 936 : R
Ipnopidae sp. : 1078 : R
Coryphaenoides rupestris : 566 : R
Trachyrincus sp. : 446 : R
Polyacanthonotus rissoanus : 552 : R
Notacanthiformes sp. 1 : 1012 : R
cf. Rouleina attrita : 1074 : R
Actinopterygii sp. 3 : 930 : R

Number of species = 30

© Marine Institute, MERC Consultants, Bernard Picton 2022