03/31/2025
In 2020, scientists discovered Henneguya salminicola, a microscopic parasite that thrives without oxygen.
This organism, related to jellyfish and corals, resides within salmon muscle tissue and lacks mitochondria—the cellular structures responsible for oxygen-based energy production. Instead, it has adapted to generate energy anaerobically, challenging the long-held belief that all multicellular life requires oxygen. 
Earlier, in 2010, researchers identified three new species of multicellular organisms in the oxygen-depleted sediments of the Mediterranean Sea’s L’Atalante basin.
Among them, Spinoloricus cinziae was notable for its ability to live entirely without oxygen.
These organisms possess unique cellular structures resembling hydrogenosomes, which facilitate anaerobic energy production, further expanding our understanding of life’s adaptability in extreme environments. 
