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 branch of zoology that studies sponges is known as spongiology.
Hexactinellid sponges are sponges with a skeleton made of four- and/or six-pointed siliceous spicules, often referred to as glass sponges. They are usually classified along with other sponges in the phylum Porifera, but some researchers consider them sufficiently distinct to deserve their own phylum, Symplasma. Some experts believe glass sponges are the longest-lived animals on earth; these scientists tentatively estimate a maximum age of up to 15,000 years.
Karl Alfred Ritter von Zittel was a German palaeontologist best known for his Handbuch der Palaeontologie (1876–1880).
Otto Max Johannes Jaekel was a German paleontologist and geologist.
Franz Eilhard Schulze was a German anatomist and zoologist born in Eldena, near Greifswald.
Sponge reefs are reefs formed by Hexactinellid sponges, which have a skeleton made of silica, and are often referred to as glass sponges. Such reefs are now very rare, and found only on the western Canadian continental shelf. Although common in the late Jurassic period, sponge reefs were believed to have gone extinct during or shortly after the Cretaceous period, until the existing reefs were discovered in 1987–1988 - hence these sometimes being dubbed living fossils.
The cloud sponge(Aphrocallistes vastus) is a species of sea sponge in the class Hexactinellida. It is a deep-water reef-forming animal. The species was first described by F.E. Schulze in 1886.
Bucaniidae is an extinct family of Paleozoic molluscs of uncertain position possibly being either gastropods or monoplacophorans in the superfamily Bellerophontoidea. The family lived from the Lower Ordovician to the Devonian and have shells in which the apertural margins tend to flare. Most genera have a slit and selenizone, others some modification of this feature.
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.
Collignoniceratidae is a family of Upper Cretaceous ammonites characterized by typically more or less evolute shells with compressed, oval, or square whorl sections; serrate or entire keels; and dense ribs with one to 5 tubercles.
Turonia is an extinct genus of sea sponges belonging to the class Demospongiae.
Syllis ramosa is a species of polychaete worm in the family Syllidae. It is found in the deep sea where it lives within the tissues of a sponge. It was the first branching polychaete worm to be discovered, with each worm having a single head and multiple anuses.
Protomonaxonida is an extinct order of sea sponges. It is a paraphyletic group gathering the most ancient species from the Burgess Shale to modern sponges.
Lophoptychium is an extinct lychniscosidan hexasterophoran sea sponge which is a subgenus of Coeloptychium. Its remains have been found in Santonian-Maastrichtian-aged deposits in Germany and Poland. The type species, L. lobatum, was originally named as a species of Coeloptychium in 1826 but it was moved to a separate subgenus in 1872.
Myrmecioptychium is an extinct lychniscosidan hexasterophoran sea sponge, which is a subgenus of Coeloptychium. Its remains have been found in Santonian-Maastrichtian-aged deposits in Broitzem, Germany and Poland. The type species, M. bodei, was named in 1912.
Sceptrulophora is an order of hexactinellid sponges, commonly known as Glass sponges, characterized by sceptrule spicules, that is, "microscleric monactinal triaxonic spicules that include clavules with terminel umbels or smooth heads." Species of the order Sceptrulophora have existed since the Jurassic period, and still flourish today. While there is ongoing debate about the organization of various taxa in Sceptrulophora, the monophyly of the taxon Sceptrulophora is supported by the presence of sceptrules in most of the extant species, and has recently been further supported by DNA sequencing.
Euretinae is a subfamily of glass sponges in the family Euretidae.
Lefroyella is a genus of glass sponges in the subfamily Euretinae, containing 2 species.
Aspidoscopulia is a genus of glass sponge in the family Farreidae.
The Wellheim Formation is a geological formation in southern Germany deposited during the Cenomanian to earliest Turonian stages of the Upper Cretaceous.
