Baltoniodus is an extinct genus of conodonts.
The base of the Dapingian, the first stage of the Middle Ordovician, is defined as the first appearance of Baltoniodus triangularis.
[2] The Whiterock Stage refers mainly to the early Middle Ordovician in North America, it is often used in the older literature in a global sense.
Officially its start is defined by the potentially lowest occurrence of the conodont Protoprioniodus aranda or Baltoniodus triangularis.
B. gerdae has been found in the early Sandbian Bromide Formation, in Oklahoma, USA.