Wikipedia
Toarcian
The Toarcian is, in the ICS' geologic timescale, an age or stage in the Early or Lower Jurassic. It spans the time between 182.7 Ma (million years ago) and 174.1 Ma. It follows the Pliensbachian and is followed by the Aalenian.
The Toarcian age began with the Toarcian turnover, the extinction event that sets its fossil faunas apart from the previous Pliensbachian age.