Nephrolenellus geniculatus
Trilobite
Early Cambrian
Pioche Formation: C-Shale
Pioche, Lincoln County, Nevada, USA

27mm on 60mm shale.

Nephrolenellus is a genus that belongs to perhaps the most ancient trilobite group (Order Redlichiidia).  It lived only during Early Cambrian.

In the old days fossil hunters used to go to the Pioche area because they could collect trilobites from a few different localities representing different ages.