common sea pen

<em>Virgularia mirabilis</em>, the common sea pen, is a colonial marine invertebrate in the family Virgulariidae, order Pennatulacea, class Anthozoa, distributed across the northeastern Atlantic Ocean and adjacent seas, with records from Denmark, Norway, and Sweden. Sea pens are soft corals that anchor themselves in soft muddy or sandy substrates in subtidal and deeper shelf habitats, where they extend their feather-like polyp-bearing rachis into the water column to capture suspended particles and zooplankton. Each sea pen colony consists of a primary polyp that forms the central stalk and numerous secondary feeding polyps arranged along the branches. <em>Virgularia mirabilis</em> can retract rapidly into the sediment when disturbed and is capable of bioluminescence, producing flashes of blue-green light. The species is listed as Least Concern by the IUCN, though deep-sea trawling poses a recognized threat to sea pen communities across their range. Biological traits for this species remain poorly documented in the scientific literature, including detailed data on average colony lifespan, growth rates, maximum dimensions, and precise dietary composition beyond its general suspension-feeding strategy.