I was geeking out to the February issue of National Geographic last night and became fascenated with sea creatures from the article on man made reefs. How cool is this guy!?
The phosphorescent sea pen lives on soft, muddy bottoms, generally below 20m in depth. On each of the arms is a row of white, tentacled polyps, which can be seen clearly in the photograph. Each polyp has a very similar structure to the larger sea anemones.