An ectoproct, also commonly known as a bryozoan, refers to a member of a group of small aquatic invertebrate animals from the phylum Bryozoa. Ectoprocts are colonial organisms that live in marine or freshwater habitats, forming colonies composed of individual tiny organisms called zooids. The term "ectoproct" is derived from the Greek words "ektos," meaning "outside," and "proktos," meaning "anus," which alludes to the location of the anus on the zooid.
Ectoprocts are characterized by their unique structure, consisting of a flexible exoskeleton called a zooecium, within which the individual zooids reside. Each zooid has a retractable crown of tentacles called a lophophore, which is used for filter-feeding and respiration. These colonies can vary greatly in size, from a few millimeters to several centimeters, and may take on diverse shapes, such as encrustations, branching colonies, or upright forms resembling moss or lace.
Ectoprocts are filter feeders, utilizing their lophophores to capture tiny particles, such as algae and plankton, from the surrounding water. They play a crucial role in marine ecosystems by filtering large amounts of water and aiding in nutrient cycling. Ectoproct colonies are often attached to hard surfaces like rocks, shells, or underwater vegetation, and their intricate exoskeletons can accumulate over time, contributing to the formation of carbonate structures.
Due to their wide variety of forms and their ability to adapt to various environmental conditions, ectoprocts are highly diverse and can be found in both saltwater and freshwater environments worldwide. They have intrigued scientists for centuries and continue to be subjects of research in the fields of paleontology, ecology
