[B-PT05] Evolution of Chemosynthetic Ecosystem in Earth History

[BPT05-P02] Epifauna on a deep-sea hydrothermal vent squat lobster, Shinkaia crosnieri, in the Izena Hole of the Okinawa Trough

Mai Karasawa², *Hiromi Kayama WATANABE¹, Hiroshi Miyake² (1.Japan Agency for Marine-Earth Science and Technology, 2.Kitasato University)

Keywords:Biodiversity

Relationships between foundation species and their associating animals provide baseline knowledge towards elucidating biodiversity. Here, we report epibiotic animals associating with a foundation species, the squat lobster Shinkaia crosnieri, in a deep-sea hydrothermal vent field in the Okinawa Trough, Northwest Pacific, and discuss their relationships. The epibiotic fauna recorded on S. crosnieri included Amphisamytha sp., dirivultid copepod, and Lepetodrilus nux. Of note, the number of individuals of Amphisamytha sp. increased with increasing size of S. crosnieri. In particular, one S. crosnieri individual had more than 300 individuals of the dirivultid copepod, L. nux, and more than 30 individuals of Amphisamytha sp. attached to it. The results suggested that older individuals host more epifauna, contributing to greater biodiversity. Furthermore, aggregations of individuals increased habitat heterogeneity, resulting in their hosting more species.