During RV MS Merian expedition MSM75, an international, multidisciplinary team explored the Reykjanes Ridge from June to August 2018. The first area of study, Steinahóll (150–350 m depth), was chosen based on previous seismic data indicating hydrothermal activity. The sampling strategy included ship- and AUV-mounted multibeam surveys, Remotely Operated Vehicle (ROV), Epibenthic Sledge (EBS), and van Veen grab (vV) deployments....

Bryconops cyrtogaster , a poorly known species endemic from the Oyapock River at the border between French Guyana and Brazil, is redescribed herein based on examination of available type material, as well as newly collected material. Additionally, a new rheophilic species from the rio Jari rapids, lower Amazon basin, Brazil, is described. The two species belong to the subgenus Creatochanes and are unique among the congeneres f...

Motivation Traits are increasingly being used to quantify global biodiversity patterns, with trait databases growing in size and number, across diverse taxa. Despite growing interest in a trait‐based approach to the biodiversity of the deep sea, where the impacts of human activities (including seabed mining) accelerate, there is no single repository for species traits for deep‐sea chemosynthesis‐based ecosystems, including hyd...

We have studied two congeneric limid bivalves, Acesta species novum and Acesta excavata (Bivalvia: Limidae), that live in similar physical conditions but use different food sources. Acesta sp. nov. live on the giant siboglinid tubeworm Lamellibrachia luymesi at cold seeps and feed on their eggs, a continuous food source that ultimately is derived from chemosynthesis, whereas A. excavata relies on planktonic food of photosynthe...