| Acanthochaetetidae | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Porifera |
| Class: | Demospongiae |
| Order: | Clionaida |
| Family: | Acanthochaetetidae (Fischer, 1970) |
| Genera | |
See text. | |
Acanthochaetetidae is a family of sponges belonging to the order Clionaida. [1] It is largely extinct, but contains two extant genera, each of which are represented by single extant species. [2]
This family contains sclerosponges (corraline sponges) with a massive calcareous skeleton. This skeleton attaches individuals to their substrate. Living tissue coats the outermost layer of the basal skeleton. The megascleres include tylostyles (pointed at one end and a knob at the other). They are common and point outwards. The microscleres are relatively large streptasters (modified aster in which the rays radiate from an axis instead of meeting at a common center). [2] The siliceous spicules suggest close ties to Spirastrella and Diplastrella but morphological differences between the spicules the presence of an elaborately structured calcareous basal skeleton justifies the distinction of Acanthochaetetidae from Spirastrellidae.
The following genera are recognised: [1]
Sponges, the members of the phylum Porifera, are a basal animal clade as a sister of the Diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells.
The calcareoussponges of class Calcarea are members of the animal phylum Porifera, the cellular sponges. They are characterized by spicules made of calcium carbonate in the form of calcite or aragonite. While the spicules in most species have three points, in some species they have either two or four points.
Demosponges (Demospongiae) are the most diverse class in the phylum Porifera. They include 76.2% of all species of sponges with nearly 8,800 species worldwide. They are sponges with a soft body that covers a hard, often massive skeleton made of calcium carbonate, either aragonite or calcite. They are predominantly leuconoid in structure. Their "skeletons" are made of spicules consisting of fibers of the protein spongin, the mineral silica, or both. Where spicules of silica are present, they have a different shape from those in the otherwise similar glass sponges. Some species, in particular from the Antarctic, obtain the silica for spicule building from the ingestion of siliceous diatoms.
Clathrina is a genus of calcareous sponge in the family Clathrinidae. Several species formerly in Clathrina were transferred to the newly erected genera Arturia, Ernstia, Borojevia, and Brattegardia in 2013. The name is derived from the Latin word "clathratus" meaning "latticed".
Clathrina coriacea is a species of calcareous sponge belonging to the class Calcarea and family Clathrinidae. Species in the genus Clathrina are composed of calcium carbonate tube-like skeletons containing spicules. The sponge can be located in shallow waters widely distributed along North Atlantic coasts, as well as on other coasts.
Clathrina lacunosa is a species of calcareous sponge from the British Isles. The species name means "having holes" and refers to the perforations found in the sides of the sponge. It is usually found on vertical solid surfaces at depths down to 220 m. It is distributed in the north-eastern Atlantic from the Arctic to the Mediterranean. It is a fairly common sponge but is often overlooked due to its small size.
Spicules are structural elements found in most sponges. Sponge spicules are made of calcium carbonate or silica. Large spicules visible to the naked eye are referred to as megascleres, while smaller, microscopic ones are termed microscleres. The meshing of many spicules serves as the sponge's skeleton and thus it provides structural support and potentially defense against predators. The composition, size, and shape of spicules are major characters in sponge systematics and taxonomy.
Helioporacea is an order of the subclass Octocorallia that forms massive lobed crystalline calcareous skeletons in colonial corals. These corals first appeared in the Cretaceous period. It consists of two families, Helioporidae Moseley, 1876 and Lithotelestidae Bayer & Muzik, 1977.
Homaxinella is a genus of sea sponges in the family Suberitidae. The type species is Homaxinella balfourensis.
Homaxinella balfourensis is a species of sea sponge in the family Suberitidae. It is found in the seas around Antarctica and can grow in two forms, either branching out in one plane like a fan or forming an upright club-like structure.
Potamolepidae is a family of freshwater sponges, with seven genera:
Clathrina antofagastensis is a species of calcareous sponge from Chile. The species is named after Antofagasta, Chile, where the holotype was discovered.
Rossellidae is a family of glass sponges belonging to the order Lyssacinosa. The family has a cosmopolitan distribution and is found at a large range of depths.
Leuclathrina is a genus of sponges belonging to the family Leucaltidae. Species are found in the northeast Atlantic and in the Indian Ocean.
Acarnidae is a family of sponges belonging to the order Poecilosclerida. It has a global distribution, although several genera occur primarily in colder temperate waters, and several have very restricted ranges. It is estimated that there are several hundred species.
Coelosphaeridae is a family of sponges belonging to the order Poecilosclerida. Species are found across the globe.
Rosella is a genus of glass sponges in the family Rossellidae. It is found in the Antarctic and sub-Antarctic regions.
Rossella antarctica is a relatively small species of glass sponge. It is widely distributed in the southern hemisphere, particularly in the Antarctic and sub-Antarctic regions.
Monanchora is a genus of demosponges belonging to the family Crambeida. The genus contains 18 species, which have been researched for their potential use in medicine.