Pleurodictyum Coral

These coral pictures were sent to me by Dave in Pennsylvania. He found these fossils in the Mahantango Formation formed in the Devonian Period.  The corals are Pleurodictyum.

He pointed out in his message to me, "The interesting thing about the molds is you can see what the coral colony originally started to grow on. One grew on a worm tube and the other looks like it grew on a Modimorpha pelecypod. The latter mode is much more common in the thick mudstones found at Seven Stars where I've found many pelecypod shells encrusted with Pleurodictyum colonies. Kind of like the Aulopora colonies that are common on the Paraspirifer et. al. brachiopods found in the Silica Shale. It gives you insight into the environment they lived in. Since there was no solid substrate to colonize, they grew on exposed or washed in shells."

Nicely researched and very good finds.

These first two pictures are of the Pleurodictyum styloporum.

These last three images are of Pleurodictyum lenticulare or Pleurodictyum americanum.