Chinese paddlefish

The Chinese paddlefish (Psephurus gladius; : literal translation: "white sturgeon"), also known as the Chinese swordfish, is an extinct species of fish that was formerly native to the Yangtze and Yellow River basins in China. With records of specimens over and possibly in length, it was one of the largest species of freshwater fish. It was the only species in the genus Psephurus and one of two recent species of paddlefish (Polyodontidae), the other being the American paddlefish (Polyodon spathula). It was an anadromous species, meaning that it spent part of its adult life at sea, while migrating upriver to spawn. The Chinese paddlefish was officially declared extinct in 2022, with an estimated time of extinction to be by 2005, and no later than 2010, although it had become functionally extinct by 1993. The main cause of its extinction was the construction of the Gezhouba and Three Gorges dams, causing population fragmentation and blocking the anadromous spawning migration. Overfishing also played a significant role in its demise. Fishing of the Chinese paddlefish dates back centuries, with annual harvests reaching 25 tons by the 1970s. Since the 1990s, the species was officially listed by the International Union for Conservation of Nature (IUCN) as critically endangered, and was last seen alive in 2003. A 2019 paper including scientists from the Yangtze River Fisheries Research Institute found the species to be extinct. It was unanimously agreed to be extinct by the Species Survival Commission Sturgeon Specialist Group of the IUCN on 15 September 2019, with its conservation status being formally updated by the IUCN Red List in July 2022. The Chinese paddlefish had a white underbelly, and its back and head were grey. Its dorsal and anal fins were situated considerably far back on the body. The paddle-like rostrum was narrow and pointed, and was between a quarter and up to a third of total body length. Its eyes were small and round. The tail fin was heterocercal (spine extending into the upper lobe), with the lower lobe being well developed.