Article: Revision of the order Stromatoporida

The genus Stromatopora has been widely misinterpreted as characterized by vertical structural elements, but the type species, Stromatopora concentrica, has a structure, here called cassiculate, dominated by oblique elements like a chainlink fence. Only twenty-six species of the several hundred attributed to Stromatopora conform to a redefinition of the genus presented here. Cellular microstructure is distinct from microreticulate microstructure. As presently defined the Order Stromatoporida is polyphyletic. Genera that have cellular microstructure are placed in the redefined Order Stromatoporida and evolved from unknown ancestors in Llandovery time. Genera that have microreticulate microstructure are separated as the Order Syringostromatida (emended), that evolved from densastromatid ancestors about the same time. In a major episode of adaptive radiation starting in the Pridoli and culminating in Emsian time the ancestral syringostromatid, Parallelostroma, gave rise to Coenostroma, Habrostroma, Syringostroma, Columnostroma and Parallelopora. In late Early to Middle Devonian time Stromatopora radiated into Lineastroma, Arctostroma, Pseudotrupetostroma, Glyptostromoides and Taleastroma. The position of Ferestromatopora is problematic. Syringostromella coexisted with Stromatopora in Middle and Late Silurian time and gave rise to Salairella in late Early Devonian time. Concise definitions of all these genera are formulated, problems of distinguishing them are discussed, and representative species are listed.