All bryozoans are aquatic filter feeders. They are usually sessile, attaching themselves to rocks or plants. All but one genus is colonial. Most bryozoans are marine, only one Class has freshwater species.
Bryozoans are soft-bodied invertebrates. They possess a lophophore surrounding the mouth. Several short tentacles with cilia are on the lophophore, which save in the water to direct water into the mouth for feeding.
Bryozoans do not appear in the fossil record until the Ordovician (488.3 - 443.7 million years ago). They are soft-bodied and fossils are rare. It's possible they live prior to that time.
