Cyclostigma tubulosa SOLD

Cyclostigma It is a porifera belonging to the class Hexactinellida. They are commonly known as vitreous sponges. Its skeleton is composed of silica spicules and fibers of the protein spongin. Its mineral skeleton presents siliceous spicules with six rays that intersect at right angles, known as hexactines, which gives its name to the group.​