The hexactinellids, or glass sponges, are characterized by siliceous spicules consisting of six rays intersecting at right angles, much like a toy jack. Hexactinellids are widely viewed as an early branch within the Porifera because there a...
http://www.ucmp.berkeley.edu/porifera/hexactinellida.ht...
The oldest fossil sponge known is a hexactinellid. In 1996, Gehling and Rigby identified and described the oldest probable Their specimens revealed a reticulating net of spicules (as seen to the right) in the sponge body wall, ... The Amphidiscophora is the older of the two main groups of Hexactinellids, with one of...
www.ucmp.berkeley.edu/porifera/hexactinellidafr.html www.ucmp.berkeley.edu/porifera/hexactinellidafr.html
Hexactinellid - Wikipedia, the free encyclopedia
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Hexactinellid sponges are sponges with a skeleton made of four- and/or six-pointed silaceous spicules, often referred to as glass sponges . They are usually classified in the Class Hexactinellida a...
en.wikipedia.org/wiki/Hexactinellid
Because there are several very important, fundamental differences between hexactinellids and other sponges, many experts now suggest that Hexactinellida comprises a distinct phylum.
animaldiversity.ummz.umich.edu/site/accounts/informatio... animaldiversity.ummz.umich.edu/site/accounts/information/Hexactinellida.html
This is where is gets the name "glass sponge" because quite literally it is made of glass, making it the most exquisite example of the class Hexactinellida, but also as precarious and as brittle as glass can be.
animaldiversity.ummz.umich.edu/site/accounts/informatio... animaldiversity.ummz.umich.edu/site/accounts/information/Euplectella_aspergillum.html
Class Hexactinellida. The skeleton in this group of sponges is made from spicules of silica, each spicule being 6 rayed in structure and sometimes fused ...
www-biol.paisley.ac.uk/Courses/Tatner/biomedia/units/po... www-biol.paisley.ac.uk/Courses/Tatner/biomedia/units/pori3.htm
Media in category "Hexactinellida" ... ITIS link: Hexactinellida Schmidt, 1870 ... World Register of Marine Species link: Hexactinellida Schmidt, 1870 (+species list)
commons.wikimedia.org/wiki/Category:Hexactinellida commons.wikimedia.org/wiki/Category:Hexactinellida
Unfortunately, it is not clear whether these earliest discoveries are, in fact Hexactinellida, or part of the basal "heteractinid" radiation. Botting & Butterfield (2005). ... Classification according to Fossil Record of the Hexactinellida, Valid PMPD Orders and Synopsis of the described taxa of the world;
www.palaeos.com/Invertebrates/Porifera/Hexactinellida.h... www.palaeos.com/Invertebrates/Porifera/Hexactinellida.html
1997. Cloning of Hsp70 genes from the marine sponges Sycon raphanus (Calcarea) and Rhabdocalyptus dawsoni (Hexactinellida). An approach to solve the phylogeny of sponges . Biological Journal of the Linnean Society 62:581-592.
www.tolweb.org/Hexactinellida/20436 www.tolweb.org/Hexactinellida/20436