Associations in the deep-sea benthopelagic zone: the amphipod crustacean &lt;em&gt;Caprella subtilis&lt;/em&gt; (Amphipoda: Caprellidae) and the holothurian &lt;em&gt;Ellipinion kumai&lt;/em&gt; (Elasipodida: Elpidiidae)

Dhugal J Lindsay,Ichiro Takeuchi

doi:10.3989/scimar.2008.72n3519

Abstract

An association between the caprellid amphipod Caprella subtilis Mayer, 1903 and the elpidiid holothurian Ellipinion kumai (Mitsukuri, 1912) was confirmed through in situ submersible capture at 309 m depth in Sagami Bay, central Japan, and through shipboard observations. Information on this association, including behavioural and morphological data on both species, is presented. Information on the taxonomic standing of C. subtilis and related species is also introduced. Furthermore, we record swimming behaviour in the holothurian genus Ellipinion for the first time. We also introduce other biotic associations revealed during studies using submersible vehicles operated by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), including associations between benthopelagic holothurians and mysids, as well as hydrozoan polyps.

Highlights

The benthopelagic zone has recently received renewed interest as the site of biogeochemical fluxes and transformations between the benthic and pelagic oceanic compartments (Marcus and Boero, 1998; Lindsay et al, 1999; Miyake et al, 2002; Raffaelli et al, 2003; Miyake et al, 2004)
High fluxes and extensive transformations of organic matter are expected in the benthopelagic zone at 300-500 m depth, where the vertically migrating midwater fauna comes into close contact with the sea floor during the daytime period of their diel migration cycle
In addition to the topological diversity offered by the sediment-water interface, the effect of interspecies interactions and associations can be expected to heighten biodiversity in the benthopelagic zone

Summary

Introduction

The benthopelagic zone has recently received renewed interest as the site of biogeochemical fluxes and transformations between the benthic and pelagic oceanic compartments (Marcus and Boero, 1998; Lindsay et al, 1999; Miyake et al, 2002; Raffaelli et al, 2003; Miyake et al, 2004). High fluxes and extensive transformations of organic matter are expected in the benthopelagic zone at 300-500 m depth, where the vertically migrating midwater fauna comes into close contact with the sea floor during the daytime period of their diel migration cycle. These transition zones between two adjacent ecological communities, in this case the midwater and benthic communities, are termed ecotones. In addition to the topological diversity offered by the sediment-water interface, the effect of interspecies interactions and associations can be expected to heighten biodiversity in the benthopelagic zone

Methods

Results

Discussion

Conclusion