Bryozoa are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about 0.5 millimetres long, they have a special feeding structure called a lophophore, a "crown" of tentacles used for filter feeding. Most marine bryozoans live in tropical waters, but a few are found in oceanic trenches and polar waters. The bryozoans are classified as the marine bryozoans (Stenolaemata), freshwater bryozoans (Phylactolaemata), and mostly-marine bryozoans (Gymnolaemata), a few members of which prefer brackish water. 5,869 living species are known. At least two genera are solitary ; the rest are colonial.
Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian through the Lower Carboniferous (Mississippian). A possible early graptolite, Chaunograptus, is known from the Middle Cambrian. Recent analyses have favored the idea that the living pterobranch Rhabdopleura represents an extant graptolite which diverged from the rest of the group in the Cambrian. Fossil graptolites and Rhabdopleura share a colony structure of interconnected zooids housed in organic tubes (theca) which have a basic structure of stacked half-rings (fuselli). Most extinct graptolites belong to two major orders: the bush-like sessile Dendroidea and the planktonic, free-floating Graptoloidea. These orders most likely evolved from encrusting pterobranchs similar to Rhabdopleura. Due to their widespread abundance, planktonic lifestyle, and well-traced evolutionary trends, graptoloids in particular are useful index fossils for the Ordovician and Silurian periods.
Gymnolaemata are a class of Bryozoans. Gymnolaemata are sessile, mostly marine organisms and grow on the surfaces of rocks, kelp, and in some cases on animals, like fish. Zooids are cylindrical or flattened. The lophophore is protruded by action of muscles pulling on the frontal wall. This order includes the majority of living bryozoan species.
Cheilostomatida, also called Cheilostomata, is an order of Bryozoa in the class Gymnolaemata.
Membraniporidae is a bryozoan family in the order Cheilostomatida. Membranipora form encrusting or erect colonies; they are unilaminar or bilaminar and weakly to well-calcified. Zooids have vertical and basal calcified walls, but virtually no frontal calcified wall: most of the frontal surface is occupied by frontal membrane. An intertentacular organ is also present. The larvae are not brooded. The ancestrula is generally twinned. Kenozooids may be present in a few species; modified zooids analogous to avicularia are rare.
Membranipora is a genus of bryozoans in the family Membraniporidae. A typical example is the widely distributed species Membranipora membranacea that commonly encrusts seaweeds, particularly fronds of the kelps Laminaria digitata, L. hyperborea, and Saccorhiza polyschides.
Membranipora membranacea is a very widely distributed species of marine bryozoan known from the Atlantic and Pacific Oceans, usually in temperate zone environments. This bryozoan is a colonial organism characterized by a thin, mat-like encrustation, white to gray in color. It may be known colloquially as the coffin box, sea-mat or lacy crust bryozoan and is often abundantly found encrusting seaweeds, particularly kelps.
Cyclostomatida, or cyclostomata, are an ancient order of stenolaemate bryozoans which first appeared in the Lower Ordovician. It consists of 7+ suborders, 59+ families, 373+ genera, and 666+ species. The cyclostome bryozoans were dominant in the Mesozoic; since that era, they have decreased. Currently, cyclostomes seldom constitute more than 20% of the species recorded in regional bryozoan faunas.
Phylactolaemata is a class of the phylum Bryozoa whose members live only in freshwater environments. Like all bryozoans, they filter feed by means of an extensible "crown" of ciliated tentacles called a lophophore, and like nearly all bryozoans, they live in colonies, each of which consists of clones of the founding member. Unlike those of some marine bryozoans, phylactolaemate colonies consist of only one type of zooid, the feeding forms known as autozooids. These are supported by an unmineralized "exoskeleton" made of gelatinous material or protein, secreted by the zooids. The class contains only one extant order, Plumatellida.
Conopeum seurati is a species of colonial bryozoan in the order Cheilostomatida. It is native to the northeastern Atlantic Ocean, the North Sea and the Mediterranean Sea. This species has been introduced to New Zealand and Florida.
Cryptosula pallasiana is a species of colonial bryozoan in the order Cheilostomatida. It is native to the Atlantic Ocean where it occurs in northwestern Europe and northern Africa, and the eastern seaboard of North America. It has been accidentally introduced to the western coast of North America and to other parts of the world.
Watersipora subtorquata, commonly known as the red-rust bryozoan, is a species of colonial bryozoan in the family Watersiporidae. It is unclear from where it originated but it is now present in many warm-water coastal regions throughout the world, and has become invasive on the west coast of North America and in Australia and New Zealand.
Catenicella elegans is a species of bryozoans in the genus Catenicella. It is found in New Zealand.
Crisia is a genus of bryozoans in the family Crisiidae. Some species are known from the fossil record.
Beania magellanica is a species of colonial bryozoan in the family Beaniidae. It has a cosmopolitan distribution, occurring in shallow waters in the Atlantic and Pacific Oceans and in Antarctica.
Electra posidoniae is a species of bryozoan in the family Electridae. It is endemic to the Mediterranean Sea, and is commonly known as the Neptune-grass bryozoan because it is exclusively found growing on seagrasses, usually on Neptune grass, but occasionally on eelgrass.
Chorizopora brongniartii is a species of bryozoan in the family Chorizoporidae. It is an encrusting bryozoan, the colonies forming spreading patches. It has a widespread distribution in tropical and temperate seas.
Hornera is a genus of bryozoans belonging to the family Horneridae.
Claviporella is a genus of bryozoans belonging to the family Catenicellidae.
Lichenalia is an extinct genus of cystoporate bryozoan belonging to the family Rhinoporidae. It is known from the Upper Ordovician to the Middle Silurian periods, which spanned from approximately 460 to 430 million years ago. The genus had a cosmopolitan distribution, with fossil specimens found in various regions of the world, including North America, Europe, and Asia.
