Epibenthic communities on the Chatham Rise, New Zealand

Abstract

Samples of epibenthic macrofauna were collected using a small sledge trawl from 40 stations on the Chatham Rise (42°34′-44°47'S; 175°34'E-179°03'W) at water depths of 237–2039 m. 218 taxa were collected, predominantly echinoderms, crustaceans, and molluscs. Multivariate analysis based on 85 species indicated three epibenthic communities, the shallowest characterised mainly by crustaceans and two deeper water communities mainly characterised by echinoderms: (1) a community on predominantly sandy sediments on the crest and shallower flanks of the Rise at 237–602 m that included as characteristic species Munida gracilis, Phylladiorhynchus pusillus, Campylonotus rathbunae, Pontophilus acutirostris, and Acutiserolis bromleyana (Crustacea), Amphiura lanceolata (Ophiuroidea), Cuspidaria fairchildi, and Euciroa galatheae (Bivalvia); (2) a community associated with muddy sediments at 462–1693 m that included Ypsilothuria bitentaculata and Pentadactyla longidentis (Holothuroidea), Brissopsis oldhami (Echinoidea), and Amphiophiura ornata (Ophiuroidea); and (3) a community on muddy sediments at 799–2039 m that included Ophiomusium lymani (Ophiuroidea), Porcellanaster ceruleus (Asteroidea), Gracilechinus multidentatus (Echinoidea), and Aeneator recens (Gastropoda). Bathymetric range of the communities was not symmetrical on either side of the Rise; there was a marked submergence on the north side similar to the vertical displacement of the core of the Antarctic Intermediate Water. © 1997, Copyright Taylor & Francis Group, LLC.