Stromatoporoids are among the most
important fossil sponges because of their large encrusting or massive calcareous
skeletons and extensive geologic record. On close examination of a broken
surface, fine laminae can be seen running parallel to the colony
surface. In some forms, pillars may cross the laminae at right angles
forming a grid-like pattern. On the external surface, small bumps called
may be seen. Small clusters of small channels called
diverge from the monticules.
Stromatoporoids range from the Cambrian
to the Cenozoic but flourished in the Silurian
particularly in reef environments.
Last updated on February 24, 1997-jlc.