Phoronopsis

Phoronopsis is a genus of marine invertebrates belonging to the phylum Phoronida. These small, worm-like animals are sessile, meaning they live attached to a substrate for their entire adult lives. They secrete a chitinous tube, which serves as their protective home. Phoronopsis species are filter feeders, extending a crown of ciliated tentacles called a lophophore into the water to capture microscopic food particles. The lophophore is a distinctive feature of phoronids and is also found in other closely related groups such as brachiopods and bryozoans.

The Phoronopsis body is elongated and divided into two main regions: a mesocoel (the main body cavity containing the lophophore) and a metacoel (the posterior part of the body cavity). They possess a complete digestive system, with a mouth and an anus. Reproduction in Phoronopsis can be both sexual and asexual. Sexual reproduction involves the release of sperm and eggs into the water column, leading to planktonic larvae that eventually settle and metamorphose. Asexual reproduction can occur through budding.

Phoronopsis are found in marine environments worldwide, typically inhabiting shallow coastal waters. They often live in colonies, forming dense aggregations on various surfaces such as rocks, shells, and artificial structures. Their presence can contribute to the biodiversity and structural complexity of benthic ecosystems. The classification of Phoronopsis has undergone revisions, with different species being described and their relationships within the phylum Phoronida continuously studied.