PBDB Interval Range

458.5 - 449.6 Ma

International Chronostratigraphic Timescale			Ordovician of Ibero-Bohemia				Ordovician of Britain
Ordovician	Late Ordovician	Hirnantian	Kosovian				Ashgill	Hirnantian			443.8
		Katian	Kralodvorian	Bohdalec †				Rawtheyan			445.2
								Cautleyan			448.9 *
								Pusgillian			449.3 *
							Caradoc	Streffordian	Onnian †		449.6 *
			Berounian					Streffordian			449.7 *
								Cheneyan			451.5 *
								Burrellian			452.7 *
		Sandbian									453
									Actonian †		453.2 *
									Marshbrookian †	Woolstonian †	454.2 *
									Longvillian †		455.2 *
					Zahorany †/Vinice	Letna †					456.2 *
								Aurelucian			456.8 *
									Soudleyan †/Harnagian/Costonian		457.4 *
				Liben †					Soudleyan †/Harnagian/Costonian		458 *
	Middle Ordovician	Darriwilian					Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			458.4
			Dobrotivian								458.5 *
			Oretanian								459.7 *
								Abereiddian/Early Llanvirn			461.3 *
				Sarka †							461.7 *
		Dapingian		Klabava †							467.3
			Arenigian								468
							Arenig	Fennian			468.4 *
	Early Ordovician	Floian						Fennian			470
								Whitlandian			471.1 *
								Moridunian			474.3 *
		Tremadocian	Tremadocian				Tremadoc	Migneintian			477.7
							Tremadoc	Cressagian			480.8 *
											485 *
											485.4