This beautiful groppo (Grammatonotus sp) was observed during Dive 8 at Eifuku Seamount. At the top of the feature survey during this dive, small, colorful fish like this were very common among the rocks.

This beautiful groppo (Grammatonotus sp.) was observed during Dive 8 at Eifuku Seamount. At the top of the feature survey during this dive, small, colorful fish like this were very common among the rocks. Image courtesy of the NOAA Office of Ocean Exploration and Research, 2016 Deepwater Exploration of the Marianas. Download larger version (jpg, 1.0 MB).

Dive 8: Eifuku Seamount
21.415°N, 144.145°E, 500 meters
June 25, 2016
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Very Spiny Urchin

This urchin with very long spines was seen while exploring the crater on the southeast side of Eifuku Seamount at a depth of ~500 meters. Video courtesy of the NOAA Office of Ocean Exploration and Research, 2016 Deepwater Exploration of the Marianas. Download (mp4, 74.7 MB)

Dive 8 was conducted on the crater on the southeast side of Eifuku Seamount. The observed fauna was unexpectedly diverse – Coronaster seastars, long-spined urchins, sponges, and a variety of octocorals, including bamboo coral which appeared to be different from any described genera, were documented throughout the dive. As the remotely operated vehicle Deep Discoverer rose up a central lava dome consisting of jagged boulders with striated surfaces, much of the ridge showed diffuse low-level hydrothermal activity with temperatures reaching about 16°C. Two highlights of the dive were documenting several Randall's snappers, a commercially important species, as deep as 476 meters, constituting a new depth range extension, and an unusual mollusk that had yellow dots—a feature that has not been seen before in this genus.