Newly discovered fire amoeba reproduces at 63°C, setting a record for complex cells
Scientists have identified a new species of heat-tolerant amoeba in the hot springs of California's Lassen Volcanic National Park. The organism can reproduce at temperatures of up to 63°C, setting a new known upper temperature limit for eukaryotic life.
The findings were published in the scientific journal Cell on September 22, 2026. NASA-supported researchers say the discovery expands current understanding of the conditions under which organisms with complex cells can survive.
What makes the fire amoeba unusual?
The newly described species, Incendiamoeba cascadensis, is a single-celled organism with a nucleus and other internal cellular structures. It is commonly called the fire amoeba.
According to NASA's official report, the organism can divide and reproduce at 63°C. The previous known temperature limit for reproduction among eukaryotes was approximately 60°C.
Although the amoeba stops reproducing above 63°C, it can remain active at higher temperatures.
In laboratory experiments, researchers found that it could recover after exposure to 70°C for five minutes. Exposure to 80°C proved too extreme for recovery.
How does the organism survive extreme heat?
The scientists sequenced the amoeba's genome and examined how its genes responded to different temperatures.
They identified genes associated with protecting DNA and maintaining the stability of proteins, both of which are essential for cellular survival.
These findings offer clues about how cells with a nucleus can continue functioning in environments previously considered too hot for this type of life.
Why does the discovery matter?
The new species provides scientists with an opportunity to study the temperature limits of eukaryotic organisms and the biological mechanisms that protect their cells.
Researchers involved in astrobiology are also interested in whether similar survival mechanisms could exist in organisms living under extreme conditions elsewhere.
However, the discovery concerns an organism found on Earth. It does not establish that life exists on another planet.
