The present paper provides first data on the fauna of Holothuroidea of the Emperor Seamount Chain (ESC, northwestern Pacific). Samples were collected using ROV Comanche 18 from four guyots, Kinmei, Koko, Nintoku and Ojin, in 2019 and 2021 at depths from 750 to 2240 m during two cruises of RV Akademik M. A. Lavrentyev. Sixteen species were recognized. Orders Elasipodida and Synallactida were the most diverse. Here we provide morphological descriptions and molecular data on COI and 16S rRNA for nine species belonging to eight genera and also for three taxa identified to the family level. One genus and two species are described as new: Parvathuria dautovae gen. et sp. nov. and Peniagone koko sp. nov. Two representatives were assigned to the genus Hansenothuria; we discuss the phylogenetic position of this genus based on molecular data. Only one of the recorded taxa is known outside the Pacific Ocean. More than a half of the examined species has the closest genetic affinity to holothuroids from the Pacific, indicating predominantly local origin of the ESC holothuroid fauna.
Bathyal fauna, Distribution, DNA barcoding, Echinodermata, Molecular phylogeny, North Pacific, Sea cucumbers, Taxonomy
