A relatively recent discovery is that some sea pens (Pennatulacea) live on hard bottoms. These “rock pens” use their peduncle like a suction cup, as shown on this colony at ~2,200 meters (~7,220 feet) depth on the North Manihiki Plateau (Mountains in the Deep: Exploring the Central Pacific Basin).
Sea Pen
Image courtesy of the NOAA Office of Ocean Exploration and Research, Mountains in the Deep: Exploring the Central Pacific Basin.
A relatively recent discovery is that some sea pens (Pennatulacea) live on hard bottoms. These “rock pens” use their peduncle like a suction cup, as shown on this colony at ~2,200 meters (~7,220 feet) depth on the North Manihiki Plateau. Download larger version (jpg, 1.8 MB).
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