Stromatoporoidea

a group of fossil invertebrates. The taxonomic position of Stromatoporoidea is uncertain, and they have been arbitrarily assigned to the sponges or coelenterates.

Stromatoporoidea lived from the early Paleozoic to the late Mesozoic. They were colonial organisms. The calcareous skeleton ranged in shape from lamellar to cylindrical and spheroidal and ranged in size from several millimeters to several meters in diameter. It consisted of horizontal plates (lamellae) and vertical elements (columellae), which differed in degree of development from group to group. Very characteristic of Stromatoporoidea was a system of canals that consisted of one vertical canal and several horizontal canals branching from the vertical canal at different levels. There were approximately 70 genera, which inhabited shallow seas. Together with corals, Stromatoporoidea contributed to the formation of coral reefs in the Silurian-Devonian. The Stromatoporoidea are important in the stratigraphy of Silurian and Devonian deposits.