During the IceDivA2 expedition on RV Sonne in November 2021, specimens of a megafaunal scaphopod species were collected by Agassiz trawl (AGT) and imaged by an Ocean Floor Observation System (OFOS) in the Labrador Sea Basin at abyssal depths of 3380 to 3390 m. Morphological, morphometric and genetic analyses revealed an undescribed species of the scaphopod genus Fissidentalium, which was formally described as Fissidentalium aurae sp. nov. by Linse and Neuhaus in 2024. In-situ images of RV Sonne's OFOS system revealed a shallow inbenthic lifestyle of the scaphopod when it is associated with an anemone, leaving Lebensspuren in the soft abyssal sediments and enabled density estimation of the species. This dataset provides data for 1) Fissidentalium aurae sp. nov. presence record from AGT, shell morphometric measurements, and museum curation numbers (.csv), 2) images files (54) of specimens' shells, soft parts and radula (.jpg), 3) SEM images files (28) of radula and shell structure (.tif), 4) in-situ OFOS images (917) (.jpg), 5) Fissidentalium presence assessment of in-situ OFOS images (.csv). Katrin Linse is part of the British Antarctic Survey Polar Science for Planet Earth Programme funded by The Natural Environment Research Council (NERC) [NC-Science]. Fieldwork during expedition SO286 on RV Sonne was funded by the Federal Ministry of Education and Research (BMBF) through the IceDivA2 grant GPF 21-2_052 given to PIs Saskia Brix, Katrin Linse, Pedro Martinez Arbizu and Alexander Kieneke. Jenny Neuhaus was supported through grant GPF 21-2_052 as well as the iAtlantic project funded by EU/HORIZON 2020, Blue Growth (grant agreement No 818123).

Comparable deep-water benthos datasets collected by epibenthic sledges (EBS) with an epibenthic and a suprabenthic netsampler in the Atlantic Ocean have been gathered since 2006. They were collected during the international research expeditions: ANDEEP-SYSTCO II, BIOPEARL I, DIVA1-3, IceAGE1-3&RR, IceDIVA1,2, JR275 and Vema-TRANSIT. While EBS diversity data at high taxon level were published for ANDEEP_SYSTCO II, DIVA1-3 and Vema-TRANSIT, unpublished diversity data for BIOPEARL I, IceAGE1-3&RR, IceDIVA1, 2 and JR275 came from sample databases at DZMB Senckenberg and British Antarctic Survey, and are published here for the first time. In total, diversity data for 143 EBS deployments from 13 expeditions were available for analyses based on identification on 50 taxon levels, including phyla, subphyla, classes and orders. During all 13 expeditions EBS with an epibenthic and a suprabenthic netsampler following sampler sizes and height , enabling comparability of samples. This type of EBS was a suitable device for sampling small benthic fauna on and above the seabed, including macrofauna and small-sized megafauna. We analyse pan-Atlantic benthic data from a range (119m - 8338m) of depths. For the pan-Atlantic analyses we defined seven regions to pool EBS locations based on their position North and South of the Equator and to the mid-Atlantic Ridge (MAR): East and West of the MAR, the Vema Fracture Zone as a gap in the MAR, the Southern Ocean south of the MAR and the Puerto Rico Trench as a deep-sea trench. In this study we included data for 41 higher taxa of the initially separated 50 taxa ranging from phyla to orders. The environmental parameters for this study were provided by Bio-ORACLE, which identifies mean values for different physical and chemical variables over a 14 year time period through a combination of satellite and in-situ measurements (2000 - 2014), at a resolution of 5 arcmin. 4 multivariate analyses (principal components analysis, analysis of similarities, similarity of percentages and BioEnv BEST) were carried out on standardised abundances using PRIMER software, the results and parameters of which are presented in this dataset. Funding over the years for the sample collection and analyses was provided by multiple NERC grants and international grants. Katrin Linse, Peter Enderlein and Huw J. Griffiths were part of the British Antarctic Survey Polar Science for Planet Earth Programme funded by The Natural Environment Research Council (NERC) [NC-Science] and included the funding for the RSS James Clark Ross expeditions BIOPEARL I and JR275. This study was directly funded by the IceAGE_RR and IceDIVA grants by the German Science Foundation (DFG) and Bundesministerium fur Bildung und Forschung (BMBF) under grant numbers MSM75 (MerMet17-5), SO280 and SO286 to PIs Saskia Brix, James Taylor and Katrin Linse. Funding for previous expeditions that provided data were: IceAGE1-3, BR3843-3-1& 4-1, & SO276 (MerMet17-6). James Taylor and Karlotta Kurzel were supported via DFG grant GPF 20-3_087 as part of the IceDiva project 2021 - 2022 by DFG. Anne-Nina Lorz was funded by the German Science Foundation Project IceAGE Amphipoda, LO2543/1-1. Additionally, Angelika Brandt was granted funding (SO 237, Forderziffer 03G0237A) by the Bauer Foundation for the VEMA-Transit project. Inmaculada Frutos was supported through the junior research group''Vema TRANSIT. Puerto Rico Trench, Vema Fracture Zone and Abyssal Atlantic Biodiversity Study'' as part of the project ''Biodiversitatnachhaltige Ressourcennutzun'' (Aktenzeichen T237/25054/).