Metallogorgia melanotrichos octocorals have been observed around the world to always have one Ophiocreas oedipus brittle star intertwined in their branches. This is considered an obligate relationship, whereby one species relies completely on another species. These were common during Dive 05 of Windows to the Deep 2021; this pair was seen at a depth of 1,414 meters (4,639 feet).
Octocoral and Brittle Star
Image courtesy of NOAA Ocean Exploration, Windows to the Deep 2021.
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Metallogorgia melanotrichos octocorals have been observed around the world to always have one Ophiocreas oedipus brittle star intertwined in their branches. This is considered an obligate relationship, whereby one species relies completely on another species. These were common during Dive 05 of Windows to the Deep 2021; this pair was seen at a depth of 1,414 meters (4,639 feet).