Tuzoia, A Decorated Phyllocarid Guanshan Biota Fossil

Description: This unusual fossil is an example of a rarely-seen Phyllocarid known as Tuzoia sinensis. It is a bivalved crustacean, most well known for its distinctively-reticulated carapace. This specimen comes from what has been termed the “Guanshan Fauna”, found in the Wulongqing Formation. The Guanshan Fauna shares many genera with the slightly older Chengjiang Biota, but differs at the species level. The genus is known from the Burgess Shale and from Early/Middle Cambrian deposits of Utah. Those are largely distinguished by the presence and placement of spines on the carapace. Few examples of the genus are known from more than the carapace, as seen here. I’ve included an artist’s rendering of what this one looked like in life. This is an eminently-affordable partial specimen that displays the polygonal marking to good effect.