"global chronostratigraphic units" (Eon) Phanerozoic Eon (541.0 Ma - present) (Era) †Mesozoic Era (252.17 - 66.0 Ma) (Period) †Triassic Period (251.902 - 201.3 Ma) (Epoch) †Scythian Epoch (Stage) †Griesbachian Stage see Substage Griesbachian Substage