【六放海绵纲】
六放海绵纲（Hexactinellida）为多孔动物门的一个纲。该纲动物具有硅质骨针，有些骨针能聚合成网状的骨架。骨骼中无海绵质。本纲又称为玻璃海绵。六放海绵纲动物大多数生活在200～8500米的海底。常被用做观赏用途，主要生存于深海当中，这种海绵也与海里的甲壳类生物共生，通常会有两只，一公一母的虾类以此为家。在日本，骨骼经过人类制作之后，成为一种爱情的纪念品。英语俗名Venus' Flower Basket。而受到一定程度的欢迎。
==型态==
形体大，骨骼全由矽质骨针组成，无海绵丝。典型的大骨针多为六射三轴针，互成直角，故又称六射海绵纲。此外还有四射双轴针等。骨针往往连线形成立体格架。小骨针呈六射星状或双盘状。简单复沟型，鞭毛室大；某些古生代种类还有单沟型。元古代晚期至现代。
在众多能拿来跟玻璃相比的透明物种当中，最接近玻璃的应当属维纳斯花篮。它们长得像一个精致的花瓶，因此而得名。它们也被称作玻璃海绵，它们骨骼的主要成分是矽，这也是玻璃的主要成分。
主要特征还有海绵特有的矽质骨针，并集结成纤巧的几何网路，如偕老同穴（Venus's flower basket）一般，玻璃海绵中央腔内常寄居一对共生俪虾，虾在幼虫的时候住进去，长大之后就逃不出去了。然后两只虾被囚困其中，靠流进中央腔的水流而获食物。这样的海绵动物在日本成为了颇受欢迎的结婚礼物。
==食性==
玻璃海绵以从水中过滤而来的最小浮游生物为食，最大可以生长到两米以上，它们花瓶般的身体构造为鱼类、无脊椎动物以及其它海洋生物提供了完美的躲藏、产卵和生存的环境。玻璃海绵像珊瑚一样开辟著自己的栖息地，在一定程度上，它们就像海床上的城市，无论它们生长在何处，总是会吸引来其它的海洋生物。
== 分类 ==
六放海绵纲分为两个亚纲：
* 双盘海绵亚纲 Amphidiscophora
* 六放海绵亚纲 Hexasterophora
本纲包含以下目：
* 双盘海绵目 Amphidiscosida
* 灯笼海绵目 Lychniscosida
* 松骨海绵目 Lyssacinosida
* 权杖海绵目 Sceptrulophora
目地位未定的科：
* Aglithodictyidae
* Asthenospongiidae
* Celyphiidae
* Cliefdenellidae
* Colospongiidae
* Cystispongiidae
* Cystothalamiidae
* Dictyospongiidae
* Dierespongiidae
* Docodermatidae
* Hemidiscellidae
* Hintzespongiidae
* Hyalostellidae
* Hydnodictyidae
* Leptophragmatidae
* Multivasculatidae
* Pachyteichismatidae
* Pattersoniidae
* Pileolitidae
* Pileospongiidae
* Pillaraspongiidae
* Plieolitidae
* Porispongiidae
* Protospongiidae
* Sebargasiidae
* Staurodermatidae
* Stereodictyidae
* Stromatidiidae
* Teganiidae
* Thaumastocoeliidae
* Titusvillidae
* Titusvilliidae
* Triactinellidae
* Uphantenidae
* Wareembaiidae
目和科地位未定的属：
* Acanthactinella Hinde, 1887
* Aglithodictya Hall & Clarke, 1898
* Antrispongia Quenstedt, 1878
* Arystidictyon
* Asociatella Hurcewicz, 1985
* Astroconia Sollas, 1881
* Aulacosia Rauff, 1933
* Aulodomus Schrammen, 1936
* Australispongia Xiping & Knoll, 1996
* Azyrtalia Nazarov, 1973
* Baccispongia Quenstedt, 1877
* Belonisia Rauff, 1933
* Bothroconis King, 1850
* Botryodictya Hall & Clarke, 1898
* Caesaria Quenstedt, 1858
* Calpidospongia Wu, 1989
* Carbonella Hurcewicz & Czarniecki, 1986
* Carinthiaspongus Krainer & Mostler, 1992
* Caseispongia Quenstedt, 1878
* Chelispongia Webby & Trotter, 1993
* Chirospongia Miller, 1889
* Cincliderma Hinde, 1883
* Clepsydrospongia Hall & Clarke, 1898
* Corticospongia Caster, 1939
* Crepospongia Wu, 1989
* Crucispongia Quenstedt, 1877
* Cryptodictya Hall, 1890
* Cyathophycella Rigby & Stuart, 1988
* Cyrtobolia Pocta, 1883
* Czarnockiella Hurcewicz & Czarniecki, 1986
* Decumbispongia Botting, Muir, Li & Lin, 2013
* Dialyscyphia Hurcewicz & Czarniecki, 1986
* Diaretula Schmidt, 1879
* Dilatispongia Botting, 2004
* Diphyllospira Herrmann-Degen, 1980
* Diplopleura Regnard, 1925
* Dvorcia Nekvasilová & Štemproková, 1960
* Emploca Sollas, 1883
* Eubrochus Sollas, 1876
* Euplectinella Termier, Termier & Thibieroz, 1990
* Eutactostomium Herrmann-Degen, 1980
* Farreopsis Schrammen, 1924
* Flosculus Xiping & Knoll, 1996
* Gonamispongia Korshunov, 1968
* Gongylospongia Hall & Clarke, 1898
* Griphodictya Hall & Clarke, 1898
* Haljalaspongia Botting & Rhebergen, 2011
* Hallodictya Hall & Clarke, 1898
* Helicodictya Hall & Clarke, 1898
* Hemidiagoniella Botting, 2004
* Hemidiscella
* Hexactractiella
* Hexatractiella Mehl, 1996
* Hillendia Reid, 1964
* Hintzesnonaia
* Hodsia Moisseev, 1939
* Holasterella
* Holasterella Carter, 1879
* Hunteria Van Soest & Hooper, 2020
* Hyalocaulus Marshall & Meyer, 1877
* Hydnocerina Clarke, 1920
* Idiodictyon de Laubenfels, 1955
* Iowaspongia Thomas, 1923
* Irpaspongia Mehl & Mostler, 1994
* Ithacadictya Caster, 1939
* Kaiyangites Qian & Yin, 1984
* Koleostoma Regnard, 1925
* Kometia Webby & Trotter, 1993
* Konyrium Nazarov & Popov, 1976
* Krainerella Krainer & Mostler, 1992
* Laocaetis
* Larispongia Carrera, 1998
* Lecanocoelospongia Wu, 1989
* Lithospongia Duchassaing & Michelotti, 1864
* Lobospongia Hurcewicz, 1985
* Lonsda de Laubenfels, 1955
* Lopanella Pocta, 1883
* Lysactinella
* Mastodictya Hall & Clarke, 1898
* Mastodictyum Sollas, 1883
* Megastylia
* Mimeticosia
* Multiloqua de Laubenfels, 1955
* Multivasculatus Howell & Van Houten, 1940
* Mysterium de Laubenfels, 1955
* Nephelispongia
* Nitidus de Laubenfels, 1955
* Octobrum de Laubenfels, 1955
* Oospongia Wu, 1989
* Oxyrhizium Schrammen, 1912
* Ozospongia
* Pachaulidium Schmidt, 1880
* Pachylepisma Schrammen, 1902
* Palaeophragmodictya Gehling & Rigby, 1996
* Palaeorossella Li et al., 2019
* Palaeostauronema
* Paleophragmodictya Gehling & Rigby, 1996
* Paleostauronema Hurcewicz, 1985
* Paracraticularia Schrammen, 1936
* Parahexactinella Reid, 1963
* Petalope Pocta, 1883
* Phormosella Hinde, 1888
* Pinnatispongia Xiping & Knoll, 1996
* Placochlaenia Pomel, 1872
* Placospongia Wu, 1989
* Plecteurete Herrmann-Degen, 1980
* Plecteurette
* Plectoderma Hinde, 1883
* Plectospyris Sollas, 1883
* Pleodioria Öpik, 1961
* Polonoscyphia Hurcewicz, 1985
* Polyosepia
* Polyplectella Ruedemann, 1925
* Polyptycha Defretin-Lefranc, 1961
* Polyschema Oppliger, 1915
* Polystigmatium Schrammen, 1912
* Polysyge
* Poriferella Hurcewicz, 1985
* Porospongia d'Orbigny, 1849
* Prenehydnoceras Hurcewicz & Czarniecki, 1986
* Proeurete Schrammen, 1902
* Protoarmstrongia Caster, 1941
* Protremadictyon Hurcewicz, 1985
* Psephosyllogus Schrammen, 1936
* Pseudotragos Nutsubidze, 1965
* Pyrenospongia Wu, 1989
* Ramulospongia Hurcewicz, 1985
* Repospongia Hurcewicz & Czarniecki, 1986
* Retifungus Rietschel, 1970
* Rhabdosispongia Hall & Clarke, 1898
* Rhabdostauridium Schmidt, 1880
* Rhakistella Weller, 1931
* Rhogostomium Schrammen, 1936
* Rhombedonium Schrammen, 1936
* Rhombodictyon Whitfield, 1886
* Rhopalicna
* Rigbykia Özdikmen, 2009
* Roemerispongia Hall & Clarke, 1898
* Rosella Vassiljeva, 1988
* Rugosoderma Howell, 1957
* Scotospongia Krainer & Mostler, 1992
* Sestrocladiella Howell, 1957
* Silicunculus Bengtson, 1986
* Solusrectus Botting, 2004
* Spiractinella Hinde, 1887
* Sulugurella Pelman, Ermak, Fedorov, Luchinina, Zhuravleva, Repina, Bondarev & Borodaevskaya, 1990
* Sycodictya Ruedemann, 1925
* Synaulia Pocta, 1883
* Teganiella Rigby, 1985
* Teganium Rauff, 1894
* Testiispongia Rigby, 1983
* Textispongia Quenstedt, 1877
* Thamnodictya Hall, 1884
* Uphantena
* Uralonema
* Ursaspongia Rigby, 1985
* Ventriculita
* Walcottella de Laubenfels, 1955
* Xenoschrammenus
* Xylospongia Hérenger, 1942
* Zittelospongia Malfatti, 1901
== 参考文献 ==