Tuzoia sinensis, Decorated Phyllocarid Fossil from Chengjiang

Tuzoia sinensis Phyllocarid

Phylum Arthropoda, Subphylum Crustacea, Class Malacostraca, Subclass Phyllocarida

Geological Time: Early Cambrian (~525 million years ago)

Size: 24 mm long by 18 mm across

Fossil Site: Chengjiang Maotianshan Shales - Quiongzhusi Section, Yu’anshan Member, Heilinpu Formation, Quiongzhusi Temple Hill, Kunming, Yunnan Province, China

Tuzoia sinensisThis unusual fossil is the rarely-seen Phyllocarid known as Tuzoia sinensis Yunnan Province, China. It is a bivalved crustacean, most well known for its distinctive reticulated carapace. This specimen comes from the strata immediately above the Chengjiang Boita, and is therefore slightly younger, and more near the age of the Burgess Shale Fauna of British Columbia. The Tuzoiagenus 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. Notice that there are a few circles present on the shell that are far different than the reticulation. These are traces of brachiopods, most likely Diandongia making for a fine association piece. Their shells were not resistant enough to be preserved, so all we see are their outlines.

Also see: Chengjiang Biota Cambrian Explosion

click to enlarge

Fossil Museum Navigation:
Geological Time Paleobiology Geological History Tree of Life
Fossil Sites Fossils Evolution Fossil Record Museum Fossils