One of the most commonly observed organisms on Dive 05 was this sea pen, an
Umbellula species with four large polyps. This is a type of octocoral, a colonial animal with polyps that bear eight tentacles. The black spots in the center of each polyp are the mouths. The polyps are joined at the base, share a stomach, and there is an internal skeleton in the long rod that attaches to the bottom. This animal is specialized to live in soft sediments and stays in place by inserting a bulb into the sediment.
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