Genus CHAINODICTYON Foerste, 1887

Type species. Chainodictyon laxum Foerste, 1887, by original designation. Pennsylvanian ( Upper Carboniferous) ; USA, Ohio .

Diagnosis. Reticulate colonies, regularly anastomosing. Flattened branches bearing 3–12 rows of autozooecia. Vestibule weakly developed. Diaphragms rare. Hemisepta absent. Oval apertures arranged in a diagonal pattern. Autozooecial chambers rhombic in mid-tangential section. Styles absent. Leptozooecia common on the obverse surface of branches. Reverse wall very thin.

Remarks. Chainodictyon Foerste, 1887, differs from Rhombocladia Rogers, 1900, by having a reticulate colony form instead of a ramose one and by the absence of hemisepta. Chainodictyon differs from Kallodictyon Morozova, 1981, in its development of a thin reverse wall and by absence of leptozooecia on the reverse surface of branches.

Occurrence. Mississippian of Kazakhstan and Russia, Pennsylvanian of USA, and Russia, and Lower Permian of Russia.