any of a group of marine invertebrates constituting the phylum Pogonophora. Pogonophorans live a sedentary life in long, protective tubes on seafloors throughout the world. The common name beardworm refers to the beardlike mass of pinnate (feather-like) tentacles borne at the anterior end of many species. An intestine, which forms in embryos, disappears as development progresses. Males of the phylum are generally similar in appearance to females. Pogonophorans are the only multicellular animals that have neither mouth nor anus.
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