Thylacine (Thylacinus cynocephalus): Also known as the Tasmanian tiger, the thylacine was native to Tasmania, Australia, and New Guinea. The last known individual died in captivity in 1936.
Quagga (Equus quagga quagga): A subspecies of the plains zebra, the quagga was native to South Africa. The last wild quagga was probably shot in the late 1870s, and the last captive quagga died in 1883.
Steller's Sea Cow (Hydrodamalis gigas): Native to the North Pacific Ocean, particularly around the Commander Islands off the coast of Siberia, Steller's sea cow was hunted to extinction by the late 18th century, less than 30 years after it was discovered.
Caribbean Monk Seal (Neomonachus tropicalis): Native to the Caribbean Sea and the Gulf of Mexico, the Caribbean monk seal was declared extinct in 2008, with the last confirmed sighting in 1952.
Baiji Dolphin (Lipotes vexillifer): Native to the Yangtze River in China, the baiji dolphin was declared functionally extinct in 2006, with no confirmed sightings since 2002 due to habitat loss, pollution, and boat traffic.
Golden Toad (Incilius periglenes): Native to Costa Rica's Monteverde Cloud Forest Reserve, the golden toad was declared extinct in 1989. Its decline was attributed to climate change, habitat loss, and disease.
Pinta Island Tortoise (Chelonoidis abingdoni): Endemic to Pinta Island in the Galápagos, the Pinta Island tortoise was declared extinct in 2012 with the death of Lonesome George, the last known individual of the species.
Javan Tiger (Panthera tigris sondaica): Native to the Indonesian island of Java, the Javan tiger was declared extinct in the mid-20th century due to habitat loss, hunting, and human-wildlife conflict.