Lyssacinosida is an order of

glass sponge 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 ...

s belonging to the subclass Hexasterophora. These sponges can be recognized by the

parenchymal Parenchyma () is the bulk of functional substance in an animal organ or structure such as a tumour. In zoology it is the name for the tissue that fills the interior of flatworms. Etymology The term ''parenchyma'' is New Latin from the word ...

spicule Spicules are any of various small needle-like anatomical structures occurring in organisms Spicule may also refer to: *Spicule (sponge), small skeletal elements of sea sponges *Spicule (nematode), reproductive structures found in male nematodes ( ...

s usually being unconnected, unlike in other sponges in the subclass where the spicules form a more or less tightly connected skeleton.

Sources

Identification key for Lyssacinosa
Hexactinellida Sponge orders {{sponge-stub