Branchiocaris sp.
Middle Cambrian
Marjum Formation
House Range, Millard County UT, USA

Excellent, very large pair of 70mm and 77mm phyllocarids on 170mm x 125mm slab.

Branchiocaris is a genus of the Subclass Phyllocarida, a group of crustaceans known primarily from their bivalved carapaces.  It lived during the Middle Cambrian with its remains documented from North America and China.

Phyllocarids, as a group, date back to the Early Cambrian with one order still living today.