Lophophore

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Freshwater bryozoan with lophophore extended
Freshwater bryozoan with lophophore extended

The lophophore is a characteristic feeding organ possessed by three major groups of animals: the Brachiopoda, Bryozoa, and Phoronida. All lophophores are marine. It can most easily be described as a ring of ciliated tentacles surrounding the mouth, but it is often horseshoe-shaped or coiled. Phoronids have their lophophores in plain view, but brachiopods must be opened wide to get a good view of their lophophore.

The lophophore surrounds the mouth and is an upstream collecting system for suspension feeding. Its tentacles are hollow with extensions of a coelomic space thought to be a mesocoel. The gut is U-shaped with the anterior mouth at the center of the lophophore. The anus is also anterior, but is dorsal to the mouth, outside the ring of the lophophore.

Groups with lophophores are called lophophorates. They were traditionally considered a monophyletic group, but it now appears they are also related to phyla such as the Mollusca and Annelida, together forming the Lophotrochozoa.