Rare Trilobite and Priapulid Fossil Association from Utah

Description: Elrathia kingii only occurs in the Middle Cambrian House Range of Utah and most predominantly in the Wheeler Shale, where they are very abundantly found in dark grey to black, and highly organic shales. They are also commonly found in association with Agnostid trilobites. What makes this a most unusual specimen is that the other fossil is a priapulid worm known as Ottoia. While a common component of the Burgess Shale Fauna, few are found in the Wheeler Formation of Utah. Ottoia lived in a U-shaped burrow; some specimens are preserved in this shape, indicating that they died within their burrows as this unfortunate appears to have been, frozen in time with the trilobite for over a HALF BILLION years.