Baltoniodus triangularis in the context of "Dapingian"

The Dapingian is the third stage of the Ordovician system and the first stage of the Middle Ordovician series. It is preceded by the Floian and succeeded by the Darriwilian. The base of the Dapingian (and the top of the Floian) is defined as the first appearance of the conodont species Baltoniodus triangularis which happened about 471.3 million years ago. The Dapingian lasted for about 1.9 million years until about 469.4 million years ago.