Description of four new synallactid species (Holothuroidea, Synallactida, Synallactidae) from the tropical Western Pacific Ocean

By

Xiao, Yunlu
XIAO, Ning

Type

Article

Date of Publication

2025

Original Publication

ZooKeys

Volume

1231

Pages

347--370

Subjects

Amphigymnas , Bathyplotes , new species , ROV , Seamounts , Synallactes , taxonomy

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/zookeys.1231.142729

 

Abstract

Four synallactid specimens were collected during four deep-water benthic fauna surveys (2013–2018) conducted at three seamounts (‘Jiaolong’, ‘Y3’, and ‘M4’) and the Ganquan Plateau in the South China Sea, tropical Western Pacific Ocean, at depths ranging from 344 to 3610 m. Morphological examination of these specimens revealed four new species belonging to three genera, which are described as Synallactes tenuibrachiussp. nov., Bathyplotes liaoisp. nov., Bathyplotes varicolumnasp. nov., and Amphigymnas ganquanisp. nov. Notably, Amphigymnas ganquanisp. nov. represents the first report of an Amphigymnas species in the South China Sea. Detailed descriptions are provided for the morphological features, including the type locality, and geographic and bathymetric distributions of these species. These findings contribute to the understanding of seamount biodiversity and provide valuable insights for advancing research on seamount ecology, management, and conservation.