Type
Zone
Age range
252.5–251.902 Ma
Early Triassic
Induan
Lopingian
Changhsingian
Isarcicella isarcica
Hindeodus parvus
Clarkina zhejiangensis-Clarkina meishanensis
Clarkina deflecta-Clarkina yini
252.50252.45252.40252.35252.30252.25252.20252.15252.10252.05252.00251.95251.90