Lychniscosida

{{Short description|Order of sponges}}

{{Automatic taxobox

| fossil_range = {{fossilrange|earliest=Carnian|Middle Jurassic|recent}}

| image =

| image_caption =

| taxon = Lychniscosida

| authority = Schrammen, 1903

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Lychniscosida (sometimes spelled Lychniscosa) is an order of sponges belonging to the class Hexactinellida and subclass Hexasterophora.{{cite web |title=Lychniscosida |url=https://www.gbif.org/species/1114 |website=www.gbif.org |access-date=14 May 2021 |language=en}}{{Citation |last=Reiswig |first=Henry M. |title=Order Lychniscosida Schrammen, 1903 |date=2002 |url=https://doi.org/10.1007/978-1-4615-0747-5_142 |work=Systema Porifera: A Guide to the Classification of Sponges |pages=1377–1377 |editor-last=Hooper |editor-first=John N. A. |access-date=2023-05-02 |place=Boston, MA |publisher=Springer US |language=en |doi=10.1007/978-1-4615-0747-5_142 |isbn=978-1-4615-0747-5 |editor2-last=Van Soest |editor2-first=Rob W. M. |editor3-last=Willenz |editor3-first=Philippe|url-access=subscription }} They are dictyonal sponges (with parenchymal spicules fully fused into a 3D framework) characterized by the presence of additional struts at the nodes of the skeleton. These struts create octahedral frames, known as lychniscs ("lanterns").

Most members of the order are extinct, with their highest diversity as major reef builders in the Jurassic and Cretaceous periods.Treatise on Invertebrate Paleontology Part E, Revised. Porifera, Volume 3: Classes Demospongea, Hexactinellida, Heteractinida & Calcarea, xxxi + 872 p., 506 fig., 1 table, 2004, available [https://journals.ku.edu/InvertebratePaleo/issue/view/455 here]. {{ISBN|0-8137-3131-3}}. A few uncertain{{Cite journal |last=Pisera |first=Andrzej |last2=Bodzioch |first2=Adam |date=1991 |title=Middle Triassic lyssacinosan sponges from Upper Silesia (southern Poland), and the history of hexactinosan and Iychniscosan sponges |url=https://geojournals.pgi.gov.pl/agp/article/viewFile/9373/7921 |journal=Acta Geologica Polonica |volume=41 |issue=3–4 |pages=193–207}} claims of Triassic lychniscosids have also been reported from China.{{Cite journal |last=Wendt |first=J. |last2=Wu |first2=Xichun |last3=Reinhardt |first3=J.W. |date=1989 |title=Deep-water hexactinellid sponge mounds from the upper triassic of northern Sichuan (China) |url=https://linkinghub.elsevier.com/retrieve/pii/0031018289901004 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |language=en |volume=76 |issue=1-2 |pages=17–29 |doi=10.1016/0031-0182(89)90100-4|url-access=subscription }}{{Cite journal |last=Wendt |first=Jobst |date=2001 |title=Upper Triassic (Carnian) mud mounds from northern Sichuan (China) |url=https://geojournals.pgi.gov.pl/agp/article/viewFile/10341/8852 |journal=Acta Geologica Polonica |volume=51 |issue=1 |pages=1–13}} Only three genera are still alive today:{{cite WoRMS|171819|title=Lychniscosida|url=https://www.marinespecies.org/aphia.php?p=taxdetails&id=171819}} Lychnocystis (family Aulocystidae),{{Citation |last=Reiswig |first=Henry M. |title=Family Aulocystidae Sollas, 1887 |date=2002 |url=https://doi.org/10.1007/978-1-4615-0747-5_143 |work=Systema Porifera: A Guide to the Classification of Sponges |pages=1378–1382 |editor-last=Hooper |editor-first=John N. A. |access-date=2023-05-02 |place=Boston, MA |publisher=Springer US |language=en |doi=10.1007/978-1-4615-0747-5_143 |isbn=978-1-4615-0747-5 |editor2-last=Van Soest |editor2-first=Rob W. M. |editor3-last=Willenz |editor3-first=Philippe|url-access=subscription }} Neoaulocystis (family Aulocystidae), and Scleroplegma (family Diapleuridae).{{Citation |last=Reiswig |first=Henry M. |title=Family Diapleuridae Ijima, 1927 |date=2002 |url=https://doi.org/10.1007/978-1-4615-0747-5_144 |work=Systema Porifera: A Guide to the Classification of Sponges |pages=1383–1385 |editor-last=Hooper |editor-first=John N. A. |access-date=2023-05-02 |place=Boston, MA |publisher=Springer US |language=en |doi=10.1007/978-1-4615-0747-5_144 |isbn=978-1-4615-0747-5 |editor2-last=Van Soest |editor2-first=Rob W. M. |editor3-last=Willenz |editor3-first=Philippe|url-access=subscription }}