PBDB Interval Range

449.5 - 443.8 Ma

International Chronostratigraphic Timescale			Ordovician of China			Ordovician of Britain
Ordovician	Late Ordovician	Hirnantian	Hirnantian	Xiaoxita †/Shikou	Wufeng †	Ashgill	Hirnantian			443.8
		Katian	Chientangkiangian				Rawtheyan			445.2
							Cautleyan			448.9 *
							Pusgillian			449.3 *
			Neichianshanian/Hanjiang				Pusgillian			449.5
						Caradoc	Streffordian	Onnian †		449.6 *
							Cheneyan			451.5 *
							Burrellian			452.7 *
		Sandbian								453
								Actonian †		453.2 *
								Marshbrookian †	Woolstonian †	454.2 *
								Longvillian †		455.2 *
							Aurelucian	Longvillian †		456.8 *
							Aurelucian	Soudleyan †/Harnagian/Costonian		457.4 *
	Middle Ordovician	Darriwilian	Darriwilian	Guniu †/Hulo		Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn			458.4
				Guniu †/Hulo			Abereiddian/Early Llanvirn			461.3 *
				Hunjiang †	Dawan †/Daobaowan/Ningkuo					466.3 *
		Dapingian	Dapingian							467.3
		Dapingian	Dapingian			Arenig	Fennian			468.4 *
	Early Ordovician	Floian	Yiyangian				Fennian			470
							Whitlandian			471.1 *
							Moridunian			474.3 *
		Tremadocian	Xinchangian			Tremadoc	Migneintian			477.7
					Lianghekou †		Migneintian			477.9 *
							Cressagian			480.8 *
										485 *
										485.4