Rusophycus Trilobite Burrow

This picture shows a trace fossil or ichnofossil I have not found before. It is a trilobite burrow also referred to as a Rusophycus. It was found in the Kope Formation (Eden Group) of Carroll County, Kentucky, USA. The trace fossil dates to the Ordovician Period.

Maybe it was made by a Flexicalymene trilobite. The three main trilobite remains found in that area are Cryptolithus, Flexicalymene, and Isotelus. I originally picked up this rock because there was a branching bryozoan on the other side that was partially covered by matrix. I thought if it could be prepped out it would make a nice display specimen. Thanks to my cousin Kenny, he recognized the trace fossil on the back which was even cooler!

Homilodonta filistriata Clam Fossil

This picture shows what appears to be a Homilodonta filistriata clam or pelecypod fossil. It was found in the Kope Formation (Eden Group) of Carroll County, Kentucky, USA. It dates to the Ordovician Period. According to the fossilworks web site, it is also known as Ctenodonta filistriata and Deceptrix filistriata.

It is still in matrix and appears to have both valves.

Largest American Horn Coral

The Siphonophrentis elongata (Rafenesque & Clifford, 1820) horn coral fossil is one of the largest found in the United States. This picture shows a small fragment of the original specimen. It was well over 30 cm in length when it was alive during the Middle Devonian Period. This segment is about 5 cm long and almost 8 cm in diameter.

What is nice is the center on one end is full of crystals (maybe quartz or calcite) and smooth mineral layer at the other end. The septa divisions are still visible along the outer circumference of the horn coral fossil.

It was found in the Jeffersonville Limestone of Jefferson County, Kentucky, USA.

Notice the beekite patterns on the outer surface of the fossil in this next picture.