Pyrococcus furiosus is an extremophilic species of Archaea. It can be classified as a hyperthermophile because it thrives best under extremely high temperatures—higher than those preferred of a thermophile. It is notable for having an optimum growth temperature of 100 °C (a temperature that would destroy most living organisms), and for being one of the few organisms identified as possessing aldehyde ferredoxin oxidoreductase enzymes containing tungsten, an element rarely found in biological molecules.