This dataset contributes to the Blue Azores Program of the Azores Regional Government in partnership with the Oceano Azul Foundation, the Waitt Institute and IMAR & Okeanos Research Center of the Azores University, as well as to the European Union's Horizon 2020 research and innovation programme under grant agreement No 678760 (ATLAS) and the Azores Government PO2020 MapGES project (Acores-01-0145-FEDER-000056). This output reflects only the authors' views and the European Union cannot be held responsible for any use that may be made of the information contained therein. TM was also supported by Program Investigador from the Fundação para a Ciência e Tecnologia (FCT) (IF/01194/2013) and IFCT (POPH and QREN) Exploratory Project (IF/01194/2013/CP1199/CT0002). TM and MCS were also supported by Program Stimulus of Scientific Employment (CCCIND/03345/2020 and CCCIND/03346/2020, respectively) from the FCT and by the H2020 programme No 689518 (MERCES) and No 818123 (iAtlantic). CD-C was supported by the Azores Government PO2020 project DeepWalls (ACORES-01-0145-FEDER-000124). MR was supported by FCT PhD grant (PD/BD/111953/2015) and GHT by the Azores Government DRCT PhD grant (M3.1.a/F/052/2015). TM, CDC, MR, LR, GHT, LF and MCS also acknowledge funds provided by the FCT through the plurennial strategic project (UIDB/05634/2020) granted to Okeanos. The authors would like to thank the Portuguese Hydrographic Institute and the Portuguese Navy for the multibeam bathymetry data collected and the crew of the NRP Almirante Gago Coutinho and the ROV Luso team for their committed interest.

Annotation of Paragorgia johnsoni Gray, 1862 colonies from underwater video footage recorded during the Blue Azores 2018 Expedition with the ROV Luso onboard the NRP Almirante Gago Coutinho, Station 57, Dive 15 (June 23rd, 2018). The images correspond to the octocoral garden discovered between 545 and 595 m depth on the slopes of a small ridge-like structure located on the Mid-Atlantic Ridge, in the Azores region.