Terreneuvian

The Terreneuvian or Early Cambrian is the lowermost and oldest series of the Cambrian geological system. Its base is defined by the first appearance datum of the trace fossil Treptichnus pedum around million years ago. Its top is defined as the first appearance of trilobites in the stratigraphic record around million years ago. This series' name was formally accepted by the International Commission on Stratigraphy in 2007.

second and final stage and age of the Terreneuvian series and epoch; second of the Cambrian system and period