The Global boundary Stratotype Section and Point (GSSP) for the Base of the Changhsingian Stage (Upper Permian) is defined at the FAD of the conodont species Clarkina wangi within the lineage from C. longicuspidata to C. wangi at a point 88 cm above the base of the Changxing Limestone at the Meishan D section; this point occurs at the base of bed 4a-2, just above a flooding surface marking the second parasequence in the Changxing Limestone. The section is located between Nanjing and Shanghai, China at 31º4'55”N and 119º42'22.9”E and is freely accessible and well protected because the point is defined in the same section as the base-Triassic GSSP. Secondary markers include the first occurrence of the ammonoid Sinoceltites and the fusulinacean Palaeofusulina aff. sinensis at the same point and the first occurrence of the ammonoid Tapashanites only 42 cm higher. The point can also be correlated within a normal polarity zone, with a reversal occurring above the point, but within the C. wangi Zone. The GSSP interval includes U-Pb zircon age data, indicating that the boundary age is about 254.14 Ma.
Changhsingian-base GSSP at Meishan Section D, Zhejiang Province