Biodiversity Data Journal :
Taxonomic Paper
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Corresponding author: Diva J Amon (divaamon@gmail.com)
Academic editor: Bruno Danis
Received: 19 Jun 2017 | Accepted: 06 Aug 2017 | Published: 14 Aug 2017
© 2017 Diva Amon, Amanda Ziegler, Jeffrey Drazen, Andrei Grischenko, Astrid Leitner, Dhugal Lindsay, Janet Voight, Mary Wicksten, Craig Young, Craig Smith
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Amon D, Ziegler A, Drazen J, Grischenko A, Leitner A, Lindsay D, Voight J, Wicksten M, Young C, Smith C (2017) Megafauna of the UKSRL exploration contract area and eastern Clarion-Clipperton Zone in the Pacific Ocean: Annelida, Arthropoda, Bryozoa, Chordata, Ctenophora, Mollusca. Biodiversity Data Journal 5: e14598. https://doi.org/10.3897/BDJ.5.e14598
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There is growing interest in mining polymetallic nodules from the abyssal Clarion-Clipperton Zone (CCZ) in the tropical Pacific Ocean. Despite having been the focus of environmental studies for decades, the benthic megafauna of the CCZ remain poorly known. To predict and manage the environmental impacts of mining in the CCZ, baseline knowledge of the megafauna is essential. The ABYSSLINE Project has conducted benthic biological baseline surveys in the UK Seabed Resources Ltd polymetallic-nodule exploration contract area (UK-1). Prior to ABYSSLINE research cruises in 2013 and 2015, no biological studies had been done in this area of the eastern CCZ.
Using a Remotely Operated Vehicle and Autonomous Underwater Vehicle (as well as several other pieces of equipment), the megafauna within the UK Seabed Resources Ltd exploration contract area (UK-1) and at a site ~250 km east of the UK-1 area were surveyed, allowing us to make the first estimates of megafaunal morphospecies richness from the imagery collected. Here, we present an atlas of the abyssal annelid, arthropod, bryozoan, chordate, ctenophore and molluscan megafauna observed and collected during the ABYSSLINE cruises to the UK-1 polymetallic-nodule exploration contract area in the CCZ. There appear to be at least 55 distinct morphospecies (8 Annelida, 12 Arthropoda, 4 Bryozoa, 22 Chordata, 5 Ctenophora, and 4 Mollusca) identified mostly by morphology but also using molecular barcoding for a limited number of animals that were collected. This atlas will aid the synthesis of megafaunal presence/absence data collected by contractors, scientists and other stakeholders undertaking work in the CCZ, ultimately helping to decipher the biogeography of the megafauna in this threatened habitat.
deep-sea mining, polymetallic nodule, Clarion-Clipperton Zone, megafauna, atlas
The Clarion-Clipperton Zone (CCZ) is an abyssal region of the tropical eastern Pacific Ocean where deep-sea mining may take place in the near future (
Locations of megafaunal surveys during the ABYSSLINE cruises, AB01 and AB02, in the Clarion-Clipperton Zone. (a) The location of the UK Seabed Resources Ltd exploration contract area (UK-1) in the eastern Pacific Ocean. (b) The locations of the 30x30-km survey areas, UK-1 Stratum A and UK-1 Stratum B, in relation to the UK-1 exploration contract area and the AB01 ROV dive site, EPIRB, which was approximately 250 km east of the UK-1 contract area. (c) The locations of ROV dives within UK-1 Stratum A, indicated by purple tracklines labelled with the dive number (e.g. RV01). Stations where imagery was collected with a baited camera (CA01) and samples collected with a baited trap (TR04, TR05, TR06) are also indicated. (d) The locations of AUV dives within UK-1 Stratum B, indicated by purple tracklines labelled with the dive number (e.g. AV01). Stations where imagery was collected with a baited camera (CA02, CA06, CA07, CA08, CA09) and samples collected with a baited trap (TR08) are also indicated. All maps were created by Seafloor Investigations Ltd for the ABYSSLINE Project using ArcGIS software (https://www.arcgis.com/features/).
The ABYSSLINE (ABYSSal BaseLINE) Project was designed to undertake benthic biological baseline studies in accordance with ISA environmental guidelines within the UK Seabed Resources Ltd (UKSRL) exploration contract area (UK-1) (
It is expected that nodule mining will drastically alter this unique deep-sea habitat with recovery expected to be slow (
Here, we present the second section (Annelida, Arthropoda, Bryozoa, Chordata, Ctenophora, and Mollusca) of an anticipated four-section image atlas of benthic megafauna that inhabit the UK-1 exploration contract area based on ROV and AUV surveys and samples collected during two cruises of the ABYSSLINE project. The first in this series (Echinodermata) has already been published (
The UKSRL exploration contract area (UK-1) is located in the eastern CCZ in the Pacific Ocean (Fig.
The ROV was equipped with two manipulators, four ROS QLEDIII lights, one 1Cam Alpha Component high-definition downward-looking "science" video camera (1080p video and 24.1 megapixel stills) and one standard-definition forward-looking “pilot” video camera. During surveys, the vehicle had substantial difficulty maintaining constant altitude, direction and velocity over the seabed, thereby limiting both the usable imagery and specimens collected.
The AB02 cruise focused on a 30x30-km stratum (UK-1 Stratum B) centered at 12°28' N, 116°36' W in the central portion of the UK-1 exploration contract area (Fig.
During both AB01 and AB02, two baited camera systems were also used to collect video of scavenging arthropods and fishes at random locations in both the UK-1 Stratum A and UK-1 Stratum B (
The ROV was the primary tool used to collect specimens on the AB01 cruise, however due to significant difficulties, few megafauna were successfully sampled (
All imagery from both "pilot" and "science" cameras on the ROV (covering roughly 8,000 m2) collected during AB01 was used during the creation of this atlas (
The criteria used for selection of megafaunal morphospecies during AB01 was that individuals were >2 cm in maximum dimension and that there was sufficient detail to identify them to a putative "species-level" morphotype (
This process estimated the number of annelid, arthropod, bryozoan, chordate, ctenophore and mollusc megafauna morphospecies in the UK-1 contract area and eastern CCZ, and will aid in delimiting species ranges in the CCZ. A concise list of morphospecies and their respective locations can be found in the Suppl. material
Seen on seafloor. No additional distinguishing features to place it beyond class Polychaeta.
Fig.
Distinct segments and thick parapodia visible. Pennate shape with body narrowing toward anterior and posterior. Often swimming near the benthos.
Fig.
Long, straight, and smooth tube emerging from seafloor with conical whorl of feathery tentacles at anterior.
Fig.
cf. Sabellidae morphospecies 1 observed in the UK-1 exploration contract area and eastern CCZ. Images (a-b) correspond with the relevant data above.
Thick tube seen protruding from sediment or attached to hard substrate. Whorl of feathery tentacles visible at anterior.
Fig.
White calcareous tube attached flat to hard substrate with feathery tentacles visible protruding from anterior end of tube.
Fig.
White calcareous tube seen projecting off hard substrate into water column with feathery tentacles visible from anterior.
Fig.
White calcareous tube with whorl of feathery tentacles visible from anterior end of tube seen on soft sediment.
Fig.
Distinct segments visible with long, paddle-like parapodia. Often swimming near the benthos.
Fig.
Colour is different so might be a different species than E. magellanicus but the body color in Eurythenes spp. varies according to the stage of the molt cycle.
Fig.
This and other amphipods can be distinguished from "true shrimp" (Order Decapoda) by having NO carapace, sessile eyes (no stalks) and three pairs of terminal appendages (uropods). Species of Eurythenes are the largest deep-sea amphipods and often are attracted to bait. Notice that there are large coxal plates at the bases of the legs - these are absent in decapod shrimps.
Fig.
Eurythenes magellanicus after collection via baited trap from the UK-1 exploration contract area. The carapace length of this specimen was 10 cm. Images (a-c) correspond with the data in (a) above.
The very large dorsal spines on the posterior part of the body are diagnostic. Often found on stalks in pairs.
Fig.
Red color, toothed rostrum, abdominal appendages very long and setose, antennal scale is round, not elongate-oval, able to swim readily. Likely to be H. spinidorsalis because this is the only species of the genus reported in this part of the Pacific.
Fig.
Hemipenaeus cf. spinidorsalis observed in the UK-1 exploration contract area. Images (a-e) correspond with the relevant data above.
Very long abdominal appendages, ability to swim, toothed rostrum, red color, elongate oval antennal scale. One of the largest deep-sea shrimp.
Fig.
Very large round eyes, stocky body, ridged margins on abdominal somites, short legs. In lateral view, carapace bears strong ridges (carinae).
Fig.
Pale color, no pigment in eyes, short but strong pincers, three pair of walking legs (pereopods) on each side (not four, as would be seen in a true crab, Brachyura). Mouthparts do not cover oral field (as they usually do in true crabs). To identify the species, one would need a dorsal view.
Fig.
Enormously long and slender legs and antennae, slender body, toothed rostrum (not visible in dorsal view), abdominal appendages usually not visible in dorsal view.
Fig.
cf. Nematocarcinus morphospecies observed in the UK-1 exploration contract area. Images (a-b) correspond with the relevant data above.
Short rostrum with few teeth, slender abdomen, very long thread-like legs, second abdominal somite does not overlap first or third somite.
Fig.
Hymenopenaeus cf. nereus observed in the UK-1 exploration contract area. Images (a-d) correspond with the relevant data above.
Elongate setose legs and rostrum, abdominal appendages do not protrude laterally, shrimp is pale pink, not red, posture is with front of body angled slightly upward from sediment surface.
Fig.
Like amphipods, isopods lack a carapace and have eyes set into the head. Very long spider-like legs and compact body. Distinguished from true sea spiders (Pycnogonida), which have a long anterior proboscis and a segmented slender body.
Fig.
cf. Munnopsidae morphospecies observed in the UK-1 exploration contract area. Images (a-b) correspond with the data in (a) above, whereas image (c) corresponds with the data in (b) above.
Ovate upper area (the capitulum) and large uncalcified areas between plates.
Fig.
Fixed-erect colonies with solid bifurcating branches possessing alternately arranged zooids facing in the opposite directions.
Fig.
cf. Smithsonius morphospecies observed in the UK-1 exploration contract area and eastern CCZ. Images (a-d) correspond with the relevant data above.
Rooted arborescent colonies with delicate bifurcating branches interconnected by transverse parallel series of chitinous tubes (fibers).
Fig.
cf. Notoplites morphospecies observed in the UK-1 exploration contract area and eastern CCZ. Images (a-d) correspond with the relevant data above.
Rooted arborescent, lightly calcified colony with slender, bifurcating branches.
Fig.
Fixed-erect colony with relatively short stem followed by four solid dichotomous branches.
Fig.
cf. Lepralielloidea morphospecies (small white colony nearest to bottom of the image) attached to a polymetallic nodule on the seafloor in the UK-1 exploration contract area. Image corresponds with the data above. Scale bar is 10 cm. Image attribution: DJ Amon & CR Smith, University of Hawai’i.
Elongate phlebobranch ascidian. A branching transparent stolon to the left of the ascidian may be part of the individual, but this is not certain.
Fig.
Very transparent ascidian approximately twice as long as it is wide. Larger incurrent siphon points anteriorally. Smaller atrial siphon points to the side. Rows of bright white spots are probably not part of the ascidian.
Fig.
cf. Phlebobranchia morphospecies 2 attached to a polymetallic nodule on the seafloor in the UK-1 exploration contract area. It is attached to another organism that resembles a narrow stalk. Image corresponds with the data above. Image attribution: DJ Amon & CR Smith, University of Hawai’i.
Attached to polymetallic nodules by a short, thick stalk of transparent tunic. Expansive incurrent siphon appears as a smiling mouth on the side of the animal. Large incurrent (atrial) siphon on top appears as a transparent region when open. Nearly circular in shape when viewed from above.
Fig.
cf. Dicopia morphospecies observed in the UK-1 exploration contract area and eastern CCZ. Image (a) corresponds with the data in (a) above whereas images (b-c) correspond with the data above in (b).
Round transparent ascidian on a thick stalk of tunic that stands higher off the bottom than Dicopia. Excurrent siphon is also much smaller than that of Dicopia.
Fig.
cf. Megalodicopia morphospecies observed in the UK-1 exploration contract area and eastern CCZ. Images (a-b) correspond with the relevant data above.
Large transparent ascidian most often attached to the side of a rock by means of a short but stout tunic stalk. In contrast to Dicopia or Megadicopia, this species is somewhat elongated laterally. The excurrent siphon is smaller in diameter than that of Dicopia.
Fig.
cf. Situla morphospecies observed in the UK-1 exploration contract area. Images (a-c) correspond with the relevant data above.
Rounded head with large rounded pectoral fins tapering to a thin tail.
Fig.
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Synaphobranchidae morphotype".
Elongated eel-like body with small pectoral fins and large jaws extending well past eye. Dorsal fin insertion before anus. Generally white to grey. No prominent lateral line pores. Notch near the end of the anal fin.
Fig.
Histiobranchus cf. bathybius observed in the UK-1 exploration contract area. Image (a) corresponds with the data in (a) above, whereas images (b-d) correspond with the data in (b) above.
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Bathysaurus mollis".
White to grey/silvery body with flattened, depressed head and gold to green, round reflective eyes. Large mouth with jaw extending past eye and prominent teeth. Typical posture is perched on substrate with all fins extended.
Fig.
Bathysaurus cf. mollis observed in the UK-1 exploration contract area. Images (a-b) correspond with the data in (a) above, whereas image (c) correponds with the data in (b).
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Ipnops morphotype".
Thin slender, black body with large, bright, reflective, plate-like eyes and large mouth.
Fig.
Ipnops cf. meadi observed in the UK-1 exploration contract area. Images (a-b) correspond with the relevant data above.
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Coryphaenoides morphotype".
Includes both species C. armatus and C. yaquinae. Both species have been recovered from the CCZ but are not readily distinguishable in photographs. Prominent snout and small chin barbel. First dorsal fin prominent and separated from the second dorsal fin which tapers to tip of whip tail. First pelvic fin ray elongated. Body color ranges from white to dark gray often with darker areas around fin insertions and eyes.
Fig.
cf. Coryphaenoides morphospecies observed in the UK-1 exploration contract area. There may be two species, Coryphaenoides armatus and Coryphaenoides yaquinae, in the in situ images, however specimens are required for identification. Images (a-b) correspond with the data in (a) above, whereas image (c-f) correspond with the data in (b-e) above.
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Halosaur morphotype".
Very slender, long body with slender, pointed head. Long whip-like tail. Head often slightly darker than rest of body. Colors range from white to blue/grey. Distinguishable by swimming pattern: majority of slender body nearly completely straight with propulsion driven by flexion of terminal ¼ to ½ of body.
Fig.
cf. Halosauridae morphospecies observed in the UK-1 exploration contract area. Images (a-b) correspond with the relevant data above.
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Ophidiidae morphotype 1".
A single dorsal fin begins in line with the pectoral fins and continues full length of body. Angular, near rectangular snout.
Fig.
cf. Ophidiidae morphospecies 1 observed in the UK-1 exploration contract area. Images (a-b) correspond with the relevant data above.
Angular head with lighter coloration along lower jaw. Rectangular body shape that maintains near maximum body depth for most of standard length. Dark contiguous dorsal and anal fins. Observed to drag body over sediment and leave a trail.
Fig.
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Ophidiidae morphotype 3".
Slender fish with large and distinctive pectoral fins. Usually a grey in colour.
Fig.
Rounded bulbous head. Blue/purple to brown coloration.
Fig.
cf. Ophidiidae morphospecies 4 observed in the UK-1 exploration contract area. Images (a-b) correspond with the relevant data above.
Bright white coloration. Small head. Dorsal fin insertion at half body length.
Fig.
cf. Ophidiidae morphospecies 5 observed in the UK-1 exploration contract area. Images (a-b) correspond with the relevant data above.
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Ophidiidae morphotype 2".
Often bright white or mottled white/brown. Head small with distinct snout and curved downturned mouth. Relatively deep-bodied. Pelvic fins reduced to two rays each and under head forward of gill slit. Readily distinguished from other ophidiids by head morphology and body depth.
Fig.
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Ophidiidae morphotype 4".
Large round, bulbous head with a tadpole-like body morphology. Reduced eyes. A variety of colormorphs exist ranging from beige to dark brown. May have lighter spots. Single dorsal contiguous with anal fin. Pelvic fins reduced to one ray each and below head. Distinguished from other ophidiids by the large rounded head.
Fig.
Bassozetus cf. nasus observed in the UK-1 exploration contract area. Images (a-c) correspond with the data in (a) above, whereas images (d-e) correspond with the data in (b-c) respectively.
Very long tapered body. Usually golden brown in color. Lower rays of pectoral fins free and stronger than upper ones. No prominent spines on head. Pelvic fins reduced to two rays each and below head. Easily distinguished from other ophidiids by the large length to body depth ratio and the free pectoral fin rays.
Fig.
Bathyonus cf. caudalis observed in the UK-1 exploration contract area and eastern CCZ. Images (a-b) correspond with the data in (a) above, whereas image (c) corresponds with the data in (b) above.
White to grey stout, eel-like body. Small body size. Very rounded head. Usually adopts a curled body position. Distinguished by small size and head morphology.
Fig.
Stout eel-like body. Distinguished from Pachycara nazca by relatively more pointed, slender head and dark dorsal and anal fin edges.
Fig.
cf. Zoarcidae morphospecies 2 observed in the UK-1 exploration contract area. Images (a-b) correspond with the data in (a) above.
Large, deep-bodied eel-like shape. Large prominent lips and small rounded eyes. Large, rounded bulbous head. Smooth, scale-less appearance. Very round, large pectoral fins. Colors range from grey to white. Distinguished from other zoarcid morphospecies by large size, rounded head and pectoral fins.
Fig.
Pachycara cf. nazca observed in the UK-1 exploration contract area and eastern CCZ. Image (a) corresponds with the data in (a) above, whereas images (b-c) correspond with the data in (b), and images (d-f) correspond with the data in (c-e) above.
Two long tentacles with filamentous side branches. Elongate body (length >twice width) tinged red throughout with gut darker. Comb rows extending over almost whole body length. Aboral end from which tentacles protude with sunken statocyst.
Fig.
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Unknown Ctenophora morphotype 1".
Whitish to transparent body with large, fleshy, rounded oral lobes but lacking auricles. Body flattened in tentacular plane. Stomodaeum not pigmented.
Fig.
Transparent body with large, rounded oral lobes. Body small in comparison with lobes. Possible pigmentation in canal system.
Fig.
Smoky pigmented body with very large, rounded oral lobes. Body width less than one-fourth of lobe width. Benthopelagic with lobes facing upwards.
Fig.
cf. Lobata morphospecies 3 observed in the UK-1 exploration contract area. Images (a-d) correspond with the relevant data above.
Dark red pigmented body flattened in tentacular plane. With no long filamentous tentacles. Long comb rows.
Fig.
Infaunal, two-valves that meet at line; view in Fig. 53 a, c virtually into expanded siphon which is extended; Fig. 53b shows closed valves. Valve length enigmatically large (ca. 3-4 cm) for these depths, essentially 50% larger than expected.
Fig.
cf. Bivalvia morphospecies observed in the eastern CCZ. Images (a-c) correspond with the relevant data above.
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Cirroteuthis morphotype".
Octopod with large paired fins emerging from lateral mantle, secondary web between the arms and primary web, and two rows of long cirri lateral to single row of arm suckers. Head about the same width as mantle. Mantle notably elongate, vague translucence. Distal arms often coiled aborally, exposing the secondary web.
Fig.
cf. Cirroteuthidae morphospecies observed in the UK-1 exploration contract area. Images (a-d) correspond with the relevant data above.
In the “Atlas of Abyssal Megafauna Morphotypes of the Clarion-Clipperton Fracture Zone” created for the ISA (http://ccfzatlas.com/), this morphospecies is listed as "Grimpoteuthis morphotype".
Octopod with moderate-sized paired fins emerging from lateral mantle, simple interbrachial web, often two-toned with light mantle, darker arms/web, and two rows of cirri lateral to arm suckers. Arms often held nearly straight. Often seen near or on the seafloor.
Fig.
cf. Grimpoteuthis morphospecies observed in the UK-1 exploration contract area. Images correspond with the data above.
Finless, benthic octopod with two rows of arm suckers, head narrower than mantle, arms coiled aborally when still, extended into sediment when walking. Swimming is propelled by mantle jets, not by fins. Ventrum often darker than dorsum, but not necessarily.
Fig.
Although many of the morphospecies included here remain taxonomically ambiguous, we provide the first image atlas of annelid, arthropod, bryozoan, chordate, ctenophore and mollusc morphospecies inhabiting the UK-1 exploration contract area and the eastern CCZ. At least 55 distinct morphospecies (8 Annelida, 12 Arthropoda, 4 Bryozoa, 22 Chordata, 5 Ctenophora, and 4 Mollusca) were observed, although this is likely an underestimate given the poor image quality and presence of cryptic species (
The numbers of annelid morphospecies in this study are similar to those in the only other CCZ megafauna study that includes annelids (
The rarer megafaunal phyla in the CCZ appear to be the Bryozoa, Ctenophora and Mollusca but this study has recorded the highest diversities thus far for each of these phyla (four, five and four morphospecies respectively). Only one other megafaunal CCZ study has included bryozoans, with one species recorded (
These morphospecies represent a range of functional traits: the serpulid and sabellid polychaetes and bryozoans are sessile suspension feeders, reliant on the polymetallic nodules as hard substrate, whereas most of the arthropods, chordates, cephalopods and ctenophores, are predatory (
While this image atlas, as well as the echinoderm atlas (
The authors thank UK Seabed Resources Ltd (UKSRL) for partially supporting this research. Thanks to the Masters, crew and scientists of the RV Melville (MV1313, AB01) and the RV Thompson (TN319, AB02) for their support during fieldwork in the Clarion-Clipperton Zone, as well as to Seafloor Investigations Ltd for creating maps from the bathymetry collected. We are grateful to the ROV Remora III team from Phoenix International Holdings and the AUV REMUS 6000 team from Woods Hole Oceanographic Institution for the collection of the imagery during the UKSRL-funded AB01 and AB02 cruises respectively. Further thanks to Dr Adrian Glover and Dr Helena Wikund (Natural History Museum, London) for identifying the annelids from imagery and Dr. Dennis Gordon for his assistance with the bryozoan images. The authors are grateful to Muriel Rabone from the Natural History Museum, London, for guidance in Darwin Core. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
CRS designed the ABYSSLINE megafaunal studies and served as chief scientist on the AB01 and AB02 cruises. DJA and CRS directed ROV and AUV operations and megafaunal sampling. JD and AL directed baited-camera and baited-trap operations. DJA and AFZ were responsible for megafaunal processing at sea. DJA and AFZ processed and edited imagery and all specimens on shore, excluding the fish and arthropods samples, which AL and JD processed. MW identified the arthropods. AG identified the bryozoans. AL and JD identified the fish and the collected amphipods. CY identified the ascidians. DL identified the ctenophores and JV identified the molluscs. DJA wrote the main manuscript text and prepared the figures. DJA, CRS, AFZ, JD, AG, AL, DL, MW, JV and CY reviewed and edited the manuscript.