Faunal biodiversity of the lower abyssal and hadal zones of the Japan, Ryukyu and Izu-Ogasawara trenches (NW Pacific Ocean; 4534-9775 m)

<i>In-situ</i> video-based observations collected using multiple platforms are increasingly used for biodiversity assessments at abyssal and hadal depths, sometimes complemented by physical sampling. Here, we present an imagery-based guide and biodiversity record of organisms observed in the Japan, Ryukyu and Izu-Ogasawara trenches in the Northwest Pacific Ocean between 4534 m and 9775 m. The guide compiles morphotaxa identifications, reference imagery and observational notes from approximately 460 hours of video footage obtained through baited lander and submersible transect surveys. A total of 108 morphotaxa were observed, which are listed here with locality and depth range. The illustrated occurrence list serves as a practical reference to aid in the identification of organisms in future image-based biodiversity assessments at these depths, to support voucher specimen collections and to provide a baseline record of faunal occurrence and distribution at these localities. Additionally, this study highlights the value of utilising multiple observation platforms to improve comprehensive biodiversity and behavioural assessments in abyssal and hadal ecosystems.