baiji

The Chinese river dolphin, or baiji (Lipotes vexillifer), remains in this group, but most sources consider it to be extinct. Assorted Referencesmajor reference

…an exhaustive search for the baiji (Lipotes vexillifer), a species of river dolphin found in the Yangtze River, failed to find any. The dolphin had declined in numbers for decades, and efforts to keep the species alive in captivity were unsuccessful.

The baiji, or Chinese river dolphin (Lipotes vexillifer), was native to China’s Yangtze River. Pale blue-gray above and lighter below, it grew to 2.4 metres (8 feet). As the waters of the Yangtze grew more crowded and polluted, the baiji became the world’s most endangered cetacean.…