Demospongiae
Demosponges and coralline algae
Scientific classification
Kingdom: Animalia Phylum: Porifera Class: Demospongiae Sollas, 1885
Subclasses
Homoscleromorpha Tetractinomorpha Ceractinomorpha See text for orders. Image File history File links Download high-resolution version (1220x1832, 290 KB) Demosponges and coralline algae on a permanent photo plot. ... Genera 39 genera Coralline algae are red algae in the Family Corallinaceae characteriuzed by a thallus covered with calcareous deposits. ... Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... Animalia redirects here. ... Classes Calcarea Hexactinellida Demospongiae The sponges or poriferans (from the Greek poros pore and ferro to bear) are animals of the phylum Porifera. ... William Johnson Sollas (30 May 1849 - 20 October 1936) was a British geologist. ...

The Demospongiae are the largest class in the phylum Porifera. Their "skeletons" are made of spicules consisting of fibers of the protein spongin, the mineral silica, or both. They contain 90% of all species of sponges and are predominantly leuconid structural grade. Classes Calcarea Hexactinellida Demospongiae The sponges or poriferans (from the Greek poros pore and ferro to bear) are animals of the phylum Porifera. ... The chemical compound silicon dioxide, also known as silica, is the oxide of silicon, chemical formula SiO2. ...

There are many diverse orders in this class, including all of the large sponges. Most are marine dwellers, but several live in freshwater environments. Some species are brightly colored, and there is great variety in body shape. They reproduce both sexually and asexually.

Classification

Hooper and van Soest give the following classification of demosponges into orders:^[1]

• Subclass Homoscleromorpha Bergquist, 1978
  • Homosclerophorida Dendy, 1905
• Subclass Tetractinomorpha
  • Astrophorida Sollas, 1888
  • Chondrosida Boury-Esnault & Lopès, 1985
  • Hadromerida Topsent, 1894
  • Lithistida Sollas, 1888
  • Spirophorida Bergquist & Hogg, 1969
• Subclass Ceractinomorpha Levi, 1953
  • Agelasida Verrill, 1907
  • Dendroceratida Minchin, 1900
  • Dictyoceratida Minchin, 1900
  • Halichondrida Gray, 1867
  • Halisarcida Bergquist, 1996
  • Haplosclerida Topsent, 1928
  • Poecilosclerida Topsent, 1928
  • Verongida Bergquist, 1978
  • Verticillitida Termier & Termier, 1977

However, molecular evidence suggests that the Homoscleromorpha may not belong in this class and that other classifications may need to be revised.^[2] families Ancorinidae Schmidt, 1870 Calthropellidae Lendenfeld, 1907 Geodiidae Gray, 1867 Pachastrellidae Carter, 1875 Thrombidae Sollas, 1888 Synonyms Epipolasida Astrophorida is an order of sea sponges under the class Demospongiae. ... families Acanthochaetetidae Fischer, 1970 Alectonidae Rosell, 1996 Choanitidae Clionidae dOrbigny, 1851 Hemiasterellidae Lendenfeld, 1889 Placospongiidae Gray, 1867 Polymastiidae Gray, 1867 Sollasellidae Lendenfeld, 1887 Spirastrellidae Ridley & Dendy, 1886 Stylocordylidae Topsent, 1892 Suberitidae Schmidt, 1870 Tethyidae Gray, 1848 Timeidae Topsent, 1928 Trachycladidae Hallmann, 1917 Hadromerida is an order of sea sponges... families Samidae Sollas, 1888 Spirasigmidae Hallmann, 1912 Tetillidae Sollas, 1886 Spirophorida is an order of sea sponges belonging to the class Demospongiae. ...

References

1. ↑  J. N. A. Hooper and R. W. M. van Soest (2002). “Class Demospongiae Sollas, 1885”, Systema Porifera. A guide to the classification of sponges. New York, Boston, Dordrecht, London, Moscow: Kluwer Academic/Plenum Publishers. 
2. ↑  C. Borchiellini, C. Chombard, M. Manuel, E. Alivon, J. Vacelet, and N. Boury-Esnault (2004). "Molecular phylogeny of Demospongiae: implications for classification and scenarios of character evolution". Mol. Phylogenet. Evol. 32 (3): 823-37. 

• Barnes, R.S.K. et al (2001). The Invertebrates: A Synthesis. Oxford: Blackwell Science. ISBN 0-632-04761-5