|any of various anthozoan coelenterates of the genus Pennatula and related genera, forming fleshy feather-like colonies in warm seas: order Pennatulacea|
any of the 300 species of the order Pennatulacea, colonial invertebrate marine animals of the class Anthozoa (phylum Cnidaria). The name sea pen derives from their resemblance to quill pens. They occur in shallow and deep waters from polar seas to the tropics.
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