Pleurodictyum

Pleurodictyum is an extinct genus of tabulate corals, characterized by polygonal corallites. Colonies commonly encrust hard substrates such as rocks, shells and carbonate hardgrounds.

Distribution
Fossils of Pleurodictyum have been found in:

Argentina, Australia, Bolivia, Tajikistan, and the United States (Kentucky, Wisconsin)
 * Silurian

Algeria, Australia, Bolivia, Brazil, Canada (Ontario), China, Colombia (Floresta Formation, Altiplano Cundiboyacense), the Czech Republic, France, Germany, Luxembourg, New Zealand, South Africa, Spain, Tajikistan, Turkey, the United Kingdom, United States (Indiana, Kentucky, Michigan, New York, Ohio, Pennsylvania, Tennessee), and Venezuela
 * Devonian

Czech Republic, Mexico, and the United States (Georgia)
 * Carboniferous