Final answer:
Archaea that require high salt concentrations are known as halophiles, and they can live in harsh environments like the Great Salt Lake and the Dead Sea.
Step-by-step explanation:
Archaea that thrive in environments with high salt concentrations, like those found in the Great Salt Lake, are called halophiles. These organisms are adapted to live in conditions that would be inhospitable for most life forms due to the extreme salinity.
An example is Halobacterium salinarum, which can be found in places like the Dead Sea and some hyper-saline lakes in Antarctica and south-central Asia. Halophiles are known for their ability to perform a type of photosynthesis and their pigmentation, which often imparts a red or purple color to the waters they inhabit.
The class Halobacteria, incorrectly named before the distinction between Archaea and Bacteria was recognized, includes these salt-loving prokaryotes. Extreme environmental conditions, such as high salinity levels posed by environments like the hypersaline Dead Sea, are where these organisms excel.
Such conditions, including the presence of magnesium and other divalent cations, combine to create a uniquely challenging ecosystem.