No wild black rhinos are left in West Africa, according to the International Union for Conservation of Nature.
As well as declaring the western black rhino (Diceros bicornis longipes) extinct, the IUCN records the northern white rhino (Ceratotherium simum cottoni), a subspecies in central Africa, as being on the brink of extinction.
The last Javan rhino (Rhinoceros sondaicus) outside Java is also believed to have disappeared.
The BBC reports that five out of eight species of tuna are also classed as threatened or near-threatened.
